List of Configuration Properties

List of Configuration Properties

All Alluxio configuration settings fall into one of the six categories: Common (shared by Master and Worker), Master specific, Worker specific, User specific, Cluster specific (used for running Alluxio with cluster managers like Mesos and YARN), and Security specific (shared by Master, Worker, and User).

Common Configuration

The common configuration contains constants shared by different components.

Property Name	Default	Description
alluxio.conf.dir	${alluxio.home}/conf	The directory containing files used to configure Alluxio. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.conf.dir”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.debug	false	Set to true to enable debug mode which has additional logging and info in the Web UI.
alluxio.extensions.dir	${alluxio.home}/extensions	The directory containing Alluxio extensions.
alluxio.fuse.cached.paths.max	500	Maximum number of Alluxio paths to cache for FUSE conversion.
alluxio.fuse.debug.enabled	false	Run FUSE in debug mode, and have the fuse process log every FS request.
alluxio.fuse.fs.name	alluxio-fuse	The FUSE file system name.
alluxio.fuse.logging.threshold	10s	Logging a FUSE API call when it takes more time than the threshold.
alluxio.fuse.maxwrite.bytes	128KB	Maximum granularity of write operations, capped by the kernel to 128KB max (as of Linux 3.16.0).
alluxio.fuse.user.group.translation.enabled	false	Whether to translate Alluxio users and groups into Unix users and groups when exposing Alluxio files through the FUSE API. When this property is set to false, the user and group for all FUSE files will match the user who started the alluxio-fuse process.
alluxio.home	/opt/alluxio	Alluxio installation directory.
alluxio.job.master.bind.host	0.0.0.0	The host that the Alluxio job master will bind to.
alluxio.job.master.client.threads	1024	The number of threads the Alluxio master uses to make requests to the job master.
alluxio.job.master.embedded.journal.addresses		A comma-separated list of journal addresses for all job masters in the cluster. The format is ‘hostname1:port1,hostname2:port2,…’. Defaults to the journal addresses set for the Alluxio masters (alluxio.master.embedded.journal.addresses), but with the job master embedded journal port.
alluxio.job.master.embedded.journal.port	20003	The port to use for embedded journal communication with other job masters.
alluxio.job.master.finished.job.purge.count	-1	The maximum amount of jobs to purge at any single time when the job master reaches its maximum capacity. It is recommended to set this value when setting the capacity of the job master to a large ( > 10M) value. Default is -1 denoting an unlimited value
alluxio.job.master.finished.job.retention.time	300sec	The length of time the Alluxio Job Master should save information about completed jobs before they are discarded.
alluxio.job.master.hostname	${alluxio.master.hostname}	The hostname of the Alluxio job master.
alluxio.job.master.job.capacity	100000	The total possible number of available job statuses in the job master. This value includes running and finished jobs which are have completed within alluxio.job.master.finished.job.retention.time.
alluxio.job.master.lost.worker.interval	1sec	The time interval the job master waits between checks for lost workers.
alluxio.job.master.rpc.addresses		The list of RPC addresses to use for the job service configured in non-zookeeper HA mode. If this property is not specifically defined, it will first fall back to using alluxio.master.rpc.addresses, replacing those address ports with the port defined by alluxio.job.master.rpc.port. Otherwise the addresses are inherited from alluxio.job.master.embedded.journal.addresses using the port defined in alluxio.job.master.rpc.port
alluxio.job.master.rpc.port	20001	The port for Alluxio job master’s RPC service.
alluxio.job.master.web.bind.host	0.0.0.0	The host that the job master web server binds to.
alluxio.job.master.web.hostname	${alluxio.job.master.hostname}	The hostname of the job master web server.
alluxio.job.master.web.port	20002	The port the job master web server uses.
alluxio.job.master.worker.heartbeat.interval	1sec	The amount of time that the Alluxio job worker should wait in between heartbeats to the Job Master.
alluxio.job.master.worker.timeout	60sec	The time period after which the job master will mark a worker as lost without a subsequent heartbeat.
alluxio.job.worker.bind.host	0.0.0.0	The host that the Alluxio job worker will bind to.
alluxio.job.worker.data.port	30002	The port the Alluxio Job worker uses to send data.
alluxio.job.worker.hostname	${alluxio.worker.hostname}	The hostname of the Alluxio job worker.
alluxio.job.worker.rpc.port	30001	The port for Alluxio job worker’s RPC service.
alluxio.job.worker.threadpool.size	10	Number of threads in the thread pool for job worker. This may be adjusted to a lower value to alleviate resource saturation on the job worker nodes (CPU + IO).
alluxio.job.worker.throttling	false	Whether the job worker should throttle itself based on whether theresources are saturated.
alluxio.job.worker.web.bind.host	0.0.0.0	The host the job worker web server binds to.
alluxio.job.worker.web.port	30003	The port the Alluxio job worker web server uses.
alluxio.jvm.monitor.info.threshold	1sec	When the JVM pauses for anything longer than this, log an INFO message.
alluxio.jvm.monitor.sleep.interval	1sec	The time for the JVM monitor thread to sleep.
alluxio.jvm.monitor.warn.threshold	10sec	When the JVM pauses for anything longer than this, log a WARN message.
alluxio.locality.compare.node.ip	false	Whether try to resolve the node IP address for locality checking
alluxio.locality.node		Value to use for determining node locality
alluxio.locality.order	node,rack	Ordering of locality tiers
alluxio.locality.rack		Value to use for determining rack locality
alluxio.locality.script	alluxio-locality.sh	A script to determine tiered identity for locality checking
alluxio.logger.type	Console	The type of logger.
alluxio.logs.dir	${alluxio.work.dir}/logs	The path under Alluxio home directory to store log files. It has a corresponding environment variable $ALLUXIO_LOGS_DIR. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.logs.dir”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.logserver.hostname		The hostname of Alluxio logserver. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.logserver.hostname”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.logserver.logs.dir	${alluxio.work.dir}/logs	Default location for remote log files. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.logserver.logs.dir”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.logserver.port	45600	Default port of logserver to receive logs from alluxio servers. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.logserver.port”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.logserver.threads.max	2048	The maximum number of threads used by logserver to service logging requests.
alluxio.logserver.threads.min	512	The minimum number of threads used by logserver to service logging requests.
alluxio.metrics.conf.file	${alluxio.conf.dir}/metrics.properties	The file path of the metrics system configuration file. By default it is `metrics.properties` in the `conf` directory.
alluxio.network.connection.auth.timeout	30sec	Maximum time to wait for a connection (gRPC channel) to attempt to receive an authentication response.
alluxio.network.connection.health.check.timeout	5sec	Allowed duration for checking health of client connections (gRPC channels) before being assigned to a client. If a connection does not become active within configured time, it will be shut down and a new connection will be created for the client
alluxio.network.connection.server.shutdown.timeout	60sec	Maximum time to wait for gRPC server to stop on shutdown
alluxio.network.connection.shutdown.graceful.timeout	45sec	Maximum time to wait for connections (gRPC channels) to stop on shutdown
alluxio.network.connection.shutdown.timeout	15sec	Maximum time to wait for connections (gRPC channels) to stop after graceful shutdown attempt.
alluxio.network.host.resolution.timeout	5sec	During startup of the Master and Worker processes Alluxio needs to ensure that they are listening on externally resolvable and reachable host names. To do this, Alluxio will automatically attempt to select an appropriate host name if one was not explicitly specified. This represents the maximum amount of time spent waiting to determine if a candidate host name is resolvable over the network.
alluxio.proxy.s3.deletetype	ALLUXIO_AND_UFS	Delete type when deleting buckets and objects through S3 API. Valid options are `ALLUXIO_AND_UFS` (delete both in Alluxio and UFS), `ALLUXIO_ONLY` (delete only the buckets or objects in Alluxio namespace).
alluxio.proxy.s3.multipart.temporary.dir.suffix	_s3_multipart_tmp	Suffix for the directory which holds parts during a multipart upload.
alluxio.proxy.s3.writetype	CACHE_THROUGH	Write type when creating buckets and objects through S3 API. Valid options are `MUST_CACHE` (write will only go to Alluxio and must be stored in Alluxio), `CACHE_THROUGH` (try to cache, write to UnderFS synchronously), `ASYNC_THROUGH` (try to cache, write to UnderFS asynchronously), `THROUGH` (no cache, write to UnderFS synchronously).
alluxio.proxy.stream.cache.timeout	1hour	The timeout for the input and output streams cache eviction in the proxy.
alluxio.proxy.web.bind.host	0.0.0.0	The hostname that the Alluxio proxy’s web server runs on.
alluxio.proxy.web.hostname		The hostname Alluxio proxy’s web UI binds to.
alluxio.proxy.web.port	39999	The port Alluxio proxy’s web UI runs on.
alluxio.secondary.master.metastore.dir	${alluxio.work.dir}/secondary-metastore	The secondary master metastore work directory. Only some metastores need disk.
alluxio.site.conf.dir	${alluxio.conf.dir}/,${user.home}/.alluxio/,/etc/alluxio/	Comma-separated search path for alluxio-site.properties. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.site.conf.dir”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.table.catalog.path	/catalog	The Alluxio file path for the table catalog metadata.
alluxio.table.catalog.udb.sync.timeout	1h	The timeout period for a db sync to finish in the catalog. If a synctakes longer than this timeout, the sync will be terminated.
alluxio.table.enabled	true	(Experimental) Enables the table service.
alluxio.table.transform.manager.job.history.retention.time	300sec	The length of time the Alluxio Table Master should keep information about finished transformation jobs before they are discarded.
alluxio.table.transform.manager.job.monitor.interval	10000	Job monitor is a heartbeat thread in the transform manager, this is the time interval in milliseconds the job monitor heartbeat is run to check the status of the transformation jobs and update table and partition locations after transformation.
alluxio.test.deprecated.key		N/A
alluxio.tmp.dirs	/tmp	The path(s) to store Alluxio temporary files, use commas as delimiters. If multiple paths are specified, one will be selected at random per temporary file. Currently, only files to be uploaded to object stores are stored in these paths.
alluxio.underfs.allow.set.owner.failure	false	Whether to allow setting owner in UFS to fail. When set to true, it is possible file or directory owners diverge between Alluxio and UFS.
alluxio.underfs.cleanup.enabled	false	Whether or not to clean up under file storage periodically.Some ufs operations may not be completed and cleaned up successfully in normal ways and leave some intermediate data that needs periodical cleanup.If enabled, all the mount points will be cleaned up when a leader master starts or cleanup interval is reached. This should be used sparingly.
alluxio.underfs.cleanup.interval	1day	The interval for periodically cleaning all the mounted under file storages.
alluxio.underfs.eventual.consistency.retry.base.sleep	50ms	To handle eventually consistent storage semantics for certain under storages, Alluxio will perform retries when under storage metadata doesn’t match Alluxio’s expectations. These retries use exponential backoff. This property determines the base time for the exponential backoff.
alluxio.underfs.eventual.consistency.retry.max.num	20	To handle eventually consistent storage semantics for certain under storages, Alluxio will perform retries when under storage metadata doesn’t match Alluxio’s expectations. These retries use exponential backoff. This property determines the maximum number of retries.
alluxio.underfs.eventual.consistency.retry.max.sleep	30sec	To handle eventually consistent storage semantics for certain under storages, Alluxio will perform retries when under storage metadata doesn’t match Alluxio’s expectations. These retries use exponential backoff. This property determines the maximum wait time in the backoff.
alluxio.underfs.gcs.default.mode	0700	Mode (in octal notation) for GCS objects if mode cannot be discovered.
alluxio.underfs.gcs.directory.suffix	/	Directories are represented in GCS as zero-byte objects named with the specified suffix.
alluxio.underfs.gcs.owner.id.to.username.mapping		Optionally, specify a preset gcs owner id to Alluxio username static mapping in the format “id1=user1;id2=user2”. The Google Cloud Storage IDs can be found at the console address https://console.cloud.google.com/storage/settings . Please use the “Owners” one.
alluxio.underfs.hdfs.configuration	${alluxio.conf.dir}/core-site.xml:${alluxio.conf.dir}/hdfs-site.xml	Location of the HDFS configuration file to overwrite the default HDFS client configuration. Note that, these files must be availableon every node.
alluxio.underfs.hdfs.impl	org.apache.hadoop.hdfs.DistributedFileSystem	The implementation class of the HDFS as the under storage system.
alluxio.underfs.hdfs.prefixes	hdfs://,glusterfs:///	Optionally, specify which prefixes should run through the HDFS implementation of UnderFileSystem. The delimiter is any whitespace and/or ‘,’.
alluxio.underfs.hdfs.remote	true	Boolean indicating whether or not the under storage worker nodes are remote with respect to Alluxio worker nodes. If set to true, Alluxio will not attempt to discover locality information from the under storage because locality is impossible. This will improve performance. The default value is true.
alluxio.underfs.kodo.connect.timeout	50sec	The connect timeout of kodo.
alluxio.underfs.kodo.downloadhost		The download domain of Kodo bucket.
alluxio.underfs.kodo.endpoint		The endpoint of Kodo bucket.
alluxio.underfs.kodo.requests.max	64	The maximum number of kodo connections.
alluxio.underfs.listing.length	1000	The maximum number of directory entries to list in a single query to under file system. If the total number of entries is greater than the specified length, multiple queries will be issued.
alluxio.underfs.object.store.breadcrumbs.enabled	true	Set this to false to prevent Alluxio from creating zero byte objects during read or list operations on object store UFS. Leaving this on enables more efficient listing of prefixes.
alluxio.underfs.object.store.mount.shared.publicly	false	Whether or not to share object storage under storage system mounted point with all Alluxio users. Note that this configuration has no effect on HDFS nor local UFS.
alluxio.underfs.object.store.multi.range.chunk.size	${alluxio.user.block.size.bytes.default}	Default chunk size for ranged reads from multi-range object input streams.
alluxio.underfs.object.store.service.threads	20	The number of threads in executor pool for parallel object store UFS operations, such as directory renames and deletes.
alluxio.underfs.oss.connection.max	1024	The maximum number of OSS connections.
alluxio.underfs.oss.connection.timeout	50sec	The timeout when connecting to OSS.
alluxio.underfs.oss.connection.ttl	-1	The TTL of OSS connections in ms.
alluxio.underfs.oss.socket.timeout	50sec	The timeout of OSS socket.
alluxio.underfs.s3.admin.threads.max	20	The maximum number of threads to use for metadata operations when communicating with S3. These operations may be fairly concurrent and frequent but should not take much time to process.
alluxio.underfs.s3.connection.ttl	-1	The expiration time of S3 connections in ms. -1 means the connection will never expire.
alluxio.underfs.s3.default.mode	0700	Mode (in octal notation) for S3 objects if mode cannot be discovered.
alluxio.underfs.s3.directory.suffix	/	Directories are represented in S3 as zero-byte objects named with the specified suffix.
alluxio.underfs.s3.disable.dns.buckets	false	Optionally, specify to make all S3 requests path style.
alluxio.underfs.s3.endpoint		Optionally, to reduce data latency or visit resources which are separated in different AWS regions, specify a regional endpoint to make aws requests. An endpoint is a URL that is the entry point for a web service. For example, s3.cn-north-1.amazonaws.com.cn is an entry point for the Amazon S3 service in beijing region.
alluxio.underfs.s3.inherit.acl	true	Set this property to false to disable inheriting bucket ACLs on objects. Note that the translation from bucket ACLs to Alluxio user permissions is best effort as some S3-like storage services doe not implement ACLs fully compatible with S3.
alluxio.underfs.s3.intermediate.upload.clean.age	3day	Streaming uploads may not have been completed/aborted correctly and need periodical ufs cleanup. If ufs cleanup is enabled, intermediate multipart uploads in all non-readonly S3 mount points older than this age will be cleaned. This may impact other ongoing upload operations, so a large clean age is encouraged.
alluxio.underfs.s3.list.objects.v1	false	Whether to use version 1 of GET Bucket (List Objects) API.
alluxio.underfs.s3.max.error.retry		The maximum number of retry attempts for failed retryable requests.Setting this property will override the AWS SDK default.
alluxio.underfs.s3.owner.id.to.username.mapping		Optionally, specify a preset s3 canonical id to Alluxio username static mapping, in the format “id1=user1;id2=user2”. The AWS S3 canonical ID can be found at the console address https://console.aws.amazon.com/iam/home?#security_credential . Please expand the “Account Identifiers” tab and refer to “Canonical User ID”. Unspecified owner id will map to a default empty username
alluxio.underfs.s3.proxy.host		Optionally, specify a proxy host for communicating with S3.
alluxio.underfs.s3.proxy.port		Optionally, specify a proxy port for communicating with S3.
alluxio.underfs.s3.request.timeout	1min	The timeout for a single request to S3. Infinity if set to 0. Setting this property to a non-zero value can improve performance by avoiding the long tail of requests to S3. For very slow connections to S3, consider increasing this value or setting it to 0.
alluxio.underfs.s3.secure.http.enabled	false	Whether or not to use HTTPS protocol when communicating with S3.
alluxio.underfs.s3.server.side.encryption.enabled	false	Whether or not to encrypt data stored in S3.
alluxio.underfs.s3.signer.algorithm		The signature algorithm which should be used to sign requests to the s3 service. This is optional, and if not set, the client will automatically determine it. For interacting with an S3 endpoint which only supports v2 signatures, set this to “S3SignerType”.
alluxio.underfs.s3.socket.timeout	50sec	Length of the socket timeout when communicating with S3.
alluxio.underfs.s3.streaming.upload.enabled	false	(Experimental) If true, using streaming upload to write to S3.
alluxio.underfs.s3.streaming.upload.partition.size	64MB	Maximum allowable size of a single buffer file when using S3A streaming upload. When the buffer file reaches the partition size, it will be uploaded and the upcoming data will write to other buffer files.If the partition size is too small, S3A upload speed might be affected.
alluxio.underfs.s3.threads.max	40	The maximum number of threads to use for communicating with S3 and the maximum number of concurrent connections to S3. Includes both threads for data upload and metadata operations. This number should be at least as large as the max admin threads plus max upload threads.
alluxio.underfs.s3.upload.threads.max	20	For an Alluxio worker, this is the maximum number of threads to use for uploading data to S3 for multipart uploads. These operations can be fairly expensive, so multiple threads are encouraged. However, this also splits the bandwidth between threads, meaning the overall latency for completing an upload will be higher for more threads. For the Alluxio master, this is the maximum number of threads used for the rename (copy) operation. It is recommended that value should be greater than or equal to alluxio.underfs.object.store.service.threads
alluxio.underfs.web.connnection.timeout	60s	Default timeout for a http connection.
alluxio.underfs.web.header.last.modified	EEE, dd MMM yyyy HH:mm:ss zzz	Date format of last modified for a http response header.
alluxio.underfs.web.parent.names	Parent Directory,..,../	The text of the http link for the parent directory.
alluxio.underfs.web.titles	Index of,Directory listing for	The title of the content for a http url.
alluxio.web.cors.enabled	false	Set to true to enable Cross-Origin Resource Sharing for RESTful APIendpoints.
alluxio.web.file.info.enabled	true	Whether detailed file information are enabled for the web UI.
alluxio.web.refresh.interval	15s	The amount of time to await before refreshing the Web UI if it is set to auto refresh.
alluxio.web.threads	1	How many threads to serve Alluxio web UI.
alluxio.web.ui.enabled	true	Whether the master/worker will have Web UI enabled. If set to false, the master/worker will not have Web UI page, but the RESTful endpoints and metrics will still be available.
alluxio.work.dir	${alluxio.home}	The directory to use for Alluxio’s working directory. By default, the journal, logs, and under file storage data (if using local filesystem) are written here.
alluxio.zookeeper.address		Address of ZooKeeper.
alluxio.zookeeper.auth.enabled	true	If true, enable client-side Zookeeper authentication.
alluxio.zookeeper.connection.timeout	15s	Connection timeout for Alluxio (job) masters to select the leading (job) master when connecting to Zookeeper
alluxio.zookeeper.election.path	/alluxio/election	Election directory in ZooKeeper.
alluxio.zookeeper.enabled	false	If true, setup master fault tolerant mode using ZooKeeper.
alluxio.zookeeper.job.election.path	/job_election	N/A
alluxio.zookeeper.job.leader.path	/job_leader	N/A
alluxio.zookeeper.leader.connection.error.policy	SESSION	Connection error policy defines how errors on zookeeper connections to be treated in leader election. STANDARD policy treats every connection event as failure.SESSION policy relies on zookeeper sessions for judging failures, helping leader to retain its status, as long as its session is protected.
alluxio.zookeeper.leader.inquiry.retry	10	The number of retries to inquire leader from ZooKeeper.
alluxio.zookeeper.leader.path	/alluxio/leader	Leader directory in ZooKeeper.
alluxio.zookeeper.session.timeout	60s	Session timeout to use when connecting to Zookeeper
aws.accessKeyId		The access key of S3 bucket.
aws.secretKey		The secret key of S3 bucket.
fs.cos.access.key		The access key of COS bucket.
fs.cos.app.id		The app id of COS bucket.
fs.cos.connection.max	1024	The maximum number of COS connections.
fs.cos.connection.timeout	50sec	The timeout of connecting to COS.
fs.cos.region		The region name of COS bucket.
fs.cos.secret.key		The secret key of COS bucket.
fs.cos.socket.timeout	50sec	The timeout of COS socket.
fs.gcs.accessKeyId		The access key of GCS bucket.
fs.gcs.secretAccessKey		The secret key of GCS bucket.
fs.kodo.accesskey		The access key of Kodo bucket.
fs.kodo.secretkey		The secret key of Kodo bucket.
fs.oss.accessKeyId		The access key of OSS bucket.
fs.oss.accessKeySecret		The secret key of OSS bucket.
fs.oss.endpoint		The endpoint key of OSS bucket.
fs.swift.auth.method		Choice of authentication method: [tempauth (default), swiftauth, keystone, keystonev3].
fs.swift.auth.url		Authentication URL for REST server, e.g., http://server:8090/auth/v1.0.
fs.swift.password		The password used for user:tenant authentication.
fs.swift.region		Service region when using Keystone authentication.
fs.swift.simulation		Whether to simulate a single node Swift backend for testing purposes: true or false (default).
fs.swift.tenant		Swift user for authentication.
fs.swift.user		Swift tenant for authentication.

Master Configuration

The master configuration specifies information regarding the master node, such as the address and the port number.

Property Name	Default	Description
alluxio.master.audit.logging.enabled	false	Set to true to enable file system master audit.
alluxio.master.audit.logging.queue.capacity	10000	Capacity of the queue used by audit logging.
alluxio.master.backup.abandon.timeout	1min	Duration after which leader will abandon the backup if not received heartbeat from backup-worker.
alluxio.master.backup.connect.interval.max	30sec	Maximum delay between each connection attempt to backup-leader.
alluxio.master.backup.connect.interval.min	1sec	Minimum delay between each connection attempt to backup-leader.
alluxio.master.backup.delegation.enabled	false	Whether to delegate journals to stand-by masters in HA cluster.
alluxio.master.backup.directory	/alluxiobackups	Default directory for writing master metadata backups. This path is an absolute path of the root UFS. For example, if the root ufs directory is hdfs://host:port/alluxio/data, the default backup directory will be hdfs://host:port/alluxio_backups.
alluxio.master.backup.entry.buffer.count	10000	How many journal entries to buffer during a back-up.
alluxio.master.backup.heartbeat.interval	2sec	Interval at which follower updates the leader on ongoing backup.
alluxio.master.backup.state.lock.exclusive.duration	0ms	Alluxio master will allow only exclusive locking of the state-lock for this duration. This duration starts after masters are started for the first time. User RPCs will fail to acquire state-lock during this phase and a backup is guaranteed take the state-lock meanwhile.
alluxio.master.backup.state.lock.forced.duration	15min	Exclusive locking of the state-lock will timeout after this duration is spent on forced phase.
alluxio.master.backup.state.lock.interrupt.cycle.enabled	true	This controls whether RPCs that are waiting/holding state-lock in shared-mode will be interrupted while state-lock is taken exclusively.
alluxio.master.backup.state.lock.interrupt.cycle.interval	30sec	The interval at which the RPCs that are waiting/holding state-lock in shared-mode will be interrupted while state-lock is taken exclusively.
alluxio.master.backup.transport.timeout	30sec	Request timeout for backup messaging.
alluxio.master.bind.host	0.0.0.0	The hostname that Alluxio master binds to.
alluxio.master.daily.backup.enabled	false	Whether or not to enable daily primary master metadata backup.
alluxio.master.daily.backup.files.retained	3	The maximum number of backup files to keep in the backup directory.
alluxio.master.daily.backup.state.lock.grace.mode	FORCED	Grace mode helps taking the state-lock exclusively for backup with minimum disruption to existing RPCs. This low-impact locking phase is called grace-cycle. Two modes are supported: TIMEOUT/FORCED.TIMEOUT: Means exclusive locking will timeout if it cannot acquire the lockwith grace-cycle. FORCED: Means the state-lock will be taken forcefully if grace-cycle fails to acquire it. Forced phase might trigger interrupting of existing RPCs if it is enabled.
alluxio.master.daily.backup.state.lock.sleep.duration	10m	The duration that controls how long the lock waiter sleeps within a single grace-cycle.
alluxio.master.daily.backup.state.lock.timeout	12h	The max duration for a grace-cycle.
alluxio.master.daily.backup.state.lock.try.duration	30s	The duration that controls how long the state-lock is tried within a single grace-cycle.
alluxio.master.daily.backup.time	05:00	Default UTC time for writing daily master metadata backups. The accepted time format is hour:minute which is based on a 24-hour clock (E.g., 05:30, 06:00, and 22:04). Backing up metadata requires a pause in master metadata changes, so please set this value to an off-peak time to avoid interfering with other users of the system.
alluxio.master.embedded.journal.addresses		A comma-separated list of journal addresses for all masters in the cluster. The format is ‘hostname1:port1,hostname2:port2,…’. When left unset, Alluxio uses ${alluxio.master.hostname}:${alluxio.master.embedded.journal.port} by default
alluxio.master.embedded.journal.appender.batch.size	512KB	Amount of data that is appended from leader to followers in a single heartbeat. Setting higher values might require increasing election timeout due to increased network delay. Setting lower values might stall knowledge propagation between the leader and followers.
alluxio.master.embedded.journal.bind.host		Used to bind embedded journal servers to a proxied host.Proxy hostname will still make use of alluxio.master.embedded.journal.port for bind port.
alluxio.master.embedded.journal.catchup.retry.wait	1s	Time for embedded journal leader to wait before retrying a catch up.
alluxio.master.embedded.journal.election.timeout	10s	The election timeout for the embedded journal. When this period elapses without a master receiving any messages, the master will attempt to become the primary.Election timeout will be waited initially when the cluster is forming. So larger values for election timeout will cause longer start-up time. Smaller values might introduce instability to leadership.
alluxio.master.embedded.journal.heartbeat.interval	3s	The period between sending heartbeats from the embedded journal primary to followers. This should be less than half of the election timeout {alluxio.master.embedded.journal.election.timeout}, because the election is driven by heart beats.
alluxio.master.embedded.journal.port	19200	The port to use for embedded journal communication with other masters.
alluxio.master.embedded.journal.shutdown.timeout	10sec	Maximum time to wait for embedded journal to stop on shutdown.
alluxio.master.embedded.journal.snapshot.replication.chunk.size	4MB	The stream chunk size used by masters to replicate snapshots.
alluxio.master.embedded.journal.storage.level	DISK	The storage level for storing embedded journal logs. Use DISK for maximum durability. Use MAPPED for better performance, but some risk of losing state in case of power loss or host failure. Use MEMORY for optimal performance, but no state persistence across cluster restarts.
alluxio.master.embedded.journal.transport.max.inbound.message.size	100MB	The maximum size of a message that can be sent to the embedded journal server node.
alluxio.master.embedded.journal.transport.request.timeout.ms	5sec	Timeout for requests between embedded journal masters.
alluxio.master.embedded.journal.triggered.snapshot.wait.timeout	2hour	Maximum time to wait for the triggered snapshot to finish.
alluxio.master.embedded.journal.write.local.first.enabled	true	Whether the journal writer will attempt to write entry locally before falling back to a full remote raft client.
alluxio.master.embedded.journal.write.timeout	30sec	Maximum time to wait for a write/flush on embedded journal.
alluxio.master.file.access.time.journal.flush.interval	1h	The minimum interval between files access time update journal entries get flushed asynchronously. Setting it to a non-positive value will make the the journal update synchronous. Asynchronous update reduces the performance impact of tracking access time but can lose some access time update when master stops unexpectedly.
alluxio.master.file.access.time.update.precision	1d	The file last access time is precise up to this value. Setting it toa non-positive value will update last access time on every file access operation.Longer precision will help reduce the performance impact of tracking access time by reduce the amount of metadata writes occur while reading the same group of files repetitively.
alluxio.master.file.access.time.updater.shutdown.timeout	1sec	Maximum time to wait for access updater to stop on shutdown.
alluxio.master.filesystem.liststatus.result.message.length	10000	Count of items on each list-status response message.
alluxio.master.format.file.prefix	_format	The file prefix of the file generated in the journal directory when the journal is formatted. The master will search for a file with this prefix when determining if the journal is formatted.
alluxio.master.heartbeat.timeout	10min	Timeout between leader master and standby master indicating a lost master.
alluxio.master.hostname		The hostname of Alluxio master.
alluxio.master.journal.checkpoint.period.entries	2000000	The number of journal entries to write before creating a new journal checkpoint.
alluxio.master.journal.flush.batch.time	5ms	Time to wait for batching journal writes.
alluxio.master.journal.flush.timeout	5min	The amount of time to keep retrying journal writes before giving up and shutting down the master.
alluxio.master.journal.folder	${alluxio.work.dir}/journal	The path to store master journal logs. When using the UFS journal this could be a URI like hdfs://namenode:port/alluxio/journal. When using the embedded journal this must be a local path
alluxio.master.journal.gc.period	2min	Frequency with which to scan for and delete stale journal checkpoints.
alluxio.master.journal.gc.threshold	5min	Minimum age for garbage collecting checkpoints.
alluxio.master.journal.init.from.backup		A uri for a backup to initialize the journal from. When the master becomes primary, if it sees that its journal is freshly formatted, it will restore its state from the backup. When running multiple masters, this property must be configured on all masters since it isn’t known during startup which master will become the first primary.
alluxio.master.journal.log.size.bytes.max	10MB	If a log file is bigger than this value, it will rotate to next file.
alluxio.master.journal.retry.interval	1sec	The amount of time to sleep between retrying journal flushes
alluxio.master.journal.tailer.shutdown.quiet.wait.time	5sec	Before the standby master shuts down its tailer thread, there should be no update to the leader master’s journal in this specified time period.
alluxio.master.journal.tailer.sleep.time	1sec	Time for the standby master to sleep for when it cannot find anything new in leader master’s journal.
alluxio.master.journal.temporary.file.gc.threshold	30min	Minimum age for garbage collecting temporary checkpoint files.
alluxio.master.journal.type	EMBEDDED	The type of journal to use. Valid options are UFS (store journal in UFS), EMBEDDED (use a journal embedded in the masters), and NOOP (do not use a journal)
alluxio.master.journal.ufs.option		The configuration to use for the journal operations.
alluxio.master.jvm.monitor.enabled	true	Whether to enable start JVM monitor thread on the master. This will start a thread to detect JVM-wide pauses induced by GC or other reasons.
alluxio.master.keytab.file		Kerberos keytab file for Alluxio master.
alluxio.master.lock.pool.concurrency.level	100	Maximum concurrency level for the lock pool
alluxio.master.lock.pool.high.watermark	1000000	High watermark of lock pool size. When the size grows over the high watermark, a background thread starts evicting unused locks from the pool.
alluxio.master.lock.pool.initsize	1000	Initial size of the lock pool for master inodes.
alluxio.master.lock.pool.low.watermark	500000	Low watermark of lock pool size. When the size grows over the high watermark, a background thread will try to evict unused locks until the size reaches the low watermark.
alluxio.master.log.config.report.heartbeat.interval	1h	The interval for periodically logging the configuration check report.
alluxio.master.lost.worker.file.detection.interval	10sec	The interval between Alluxio master detections to find lost workers and files based on updates from Alluxio workers.
alluxio.master.metadata.sync.concurrency.level	6	The maximum number of concurrent sync tasks running for a given sync operation
alluxio.master.metadata.sync.executor.pool.size	The total number of threads which can concurrently execute metadata sync operations.	The number of threads used to execute all metadata syncoperations
alluxio.master.metadata.sync.ufs.prefetch.pool.size	The number of threads which can concurrently fetch metadata from UFSes during a metadata sync operations	The number of threads used to fetch UFS objects for all metadata syncoperations
alluxio.master.metastore	HEAP	The type of metastore to use, either HEAP or ROCKS. The heap metastore keeps all metadata on-heap, while the rocks metastore stores some metadata on heap and some metadata on disk. The rocks metastore has the advantage of being able to support a large namespace (1 billion plus files) without needing a massive heap size.
alluxio.master.metastore.dir	${alluxio.work.dir}/metastore	The metastore work directory. Only some metastores need disk.
alluxio.master.metastore.inode.cache.evict.batch.size	1000	The batch size for evicting entries from the inode cache.
alluxio.master.metastore.inode.cache.high.water.mark.ratio	0.85	The high water mark for the inode cache, as a ratio from high water mark to total cache size. If this is 0.85 and the max size is 10 million, the high water mark value is 8.5 million. When the cache reaches the high water mark, the eviction process will evict down to the low water mark.
alluxio.master.metastore.inode.cache.low.water.mark.ratio	0.8	The low water mark for the inode cache, as a ratio from low water mark to total cache size. If this is 0.8 and the max size is 10 million, the low water mark value is 8 million. When the cache reaches the high water mark, the eviction process will evict down to the low water mark.
alluxio.master.metastore.inode.cache.max.size	10000000	The number of inodes to cache on-heap. This only applies to off-heap metastores, e.g. ROCKS. Set this to 0 to disable the on-heap inode cache
alluxio.master.metastore.inode.enumerator.buffer.count	10000	The number of entries to buffer during read-ahead enumeration.
alluxio.master.metastore.inode.inherit.owner.and.group	true	Whether to inherit the owner/group from the parent when creating a new inode path if empty
alluxio.master.metastore.inode.iteration.crawler.count	Use {CPU core count} for enumeration	The number of threads used during inode tree enumeration.
alluxio.master.metastore.iterator.readahead.size	64MB	The read-ahead size (in bytes) for metastore iterators.
alluxio.master.metrics.service.threads	5	The number of threads in metrics master executor pool for parallel processing metrics submitted by workers or clients and update cluster metrics.
alluxio.master.metrics.time.series.interval	5min	Interval for which the master records metrics information. This affects the granularity of the metrics graphed in the UI.
alluxio.master.mount.table.root.alluxio	/	Alluxio root mount point.
alluxio.master.mount.table.root.option		Configuration for the UFS of Alluxio root mount point.
alluxio.master.mount.table.root.readonly	false	Whether Alluxio root mount point is readonly.
alluxio.master.mount.table.root.shared	true	Whether Alluxio root mount point is shared.
alluxio.master.mount.table.root.ufs	${alluxio.work.dir}/underFSStorage	The storage address of the UFS at the Alluxio root mount point.
alluxio.master.network.max.inbound.message.size	100MB	The maximum size of a message that can be sent to the Alluxio master
alluxio.master.periodic.block.integrity.check.interval	1hr	The period for the block integrity check, disabled if <= 0.
alluxio.master.periodic.block.integrity.check.repair	false	Whether the system should delete orphaned blocks found during the periodic integrity check. This is an experimental feature.
alluxio.master.persistence.blacklist		Patterns to blacklist persist, comma separated, string match, no regex. This affects any async persist call (including ASYNC_THROUGH writes and CLI persist) but does not affect CACHE_THROUGH writes. Users may want to specify temporary files in the blacklist to avoid unnecessary I/O and errors. Some examples are `.staging` and `.tmp`.
alluxio.master.persistence.checker.interval	1s	How often the master checks persistence status for files written using ASYNC_THROUGH
alluxio.master.persistence.initial.interval	1s	How often the master persistence checker checks persistence status for files written using ASYNC_THROUGH
alluxio.master.persistence.max.interval	1hr	Max wait interval for master persistence checker persistence status for files written using ASYNC_THROUGH
alluxio.master.persistence.max.total.wait.time	1day	Total wait time for master persistence checker persistence status for files written using ASYNC_THROUGH
alluxio.master.persistence.scheduler.interval	1s	How often the master schedules persistence jobs for files written using ASYNC_THROUGH
alluxio.master.principal		Kerberos principal for Alluxio master.
alluxio.master.replication.check.interval	1min	How often the master runs background process to check replication level for files
alluxio.master.rpc.addresses		A list of comma-separated host:port RPC addresses where the client should look for masters when using multiple masters without Zookeeper. This property is not used when Zookeeper is enabled, since Zookeeper already stores the master addresses.
alluxio.master.rpc.executor.core.pool.size	0	the number of threads to keep in thread pool of master RPC executor service. By default it is same as the parallelism level, but may be set to a larger value to reduce dynamic overhead if tasks regularly block. A smaller value (for example 0) is equivalent to the default.
alluxio.master.rpc.executor.keepalive	60sec	the keep alive time of a thread in master RPC executor servicelast used before this thread is terminated (and replaced if necessary).
alluxio.master.rpc.executor.max.pool.size	500	the maximum number of threads allowed for master RPC executor service. When the maximum is reached, attempts to replace blocked threads fail.
alluxio.master.rpc.executor.min.runnable	1	the minimum allowed number of core threads not blocked. To ensure progress, when too few unblocked threads exist and unexecuted tasks may exist, new threads are constructed up to the value of alluxio.master.rpc.executor.max.pool.size. A value of 1 ensures liveness. A larger value might improve throughput but might also increase overhead.
alluxio.master.rpc.executor.parallelism	2 * {CPU core count}	The parallelism level of master RPC executor service .
alluxio.master.rpc.port	19998	The port for Alluxio master’s RPC service.
alluxio.master.shell.backup.state.lock.grace.mode	TIMEOUT	Grace mode helps taking the state-lock exclusively for backup with minimum disruption to existing RPCs. This low-impact locking phase is called grace-cycle. Two modes are supported: TIMEOUT/FORCED.TIMEOUT: Means exclusive locking will timeout if it cannot acquire the lockwith grace-cycle. FORCED: Means the state-lock will be taken forcefully if grace-cycle fails to acquire it. Forced phase might trigger interrupting of existing RPCs if it is enabled.
alluxio.master.shell.backup.state.lock.sleep.duration	0	The duration that controls how long the lock waiter sleeps within a single grace-cycle.
alluxio.master.shell.backup.state.lock.timeout	1m	The max duration for a grace-cycle.
alluxio.master.shell.backup.state.lock.try.duration	1m	The duration that controls how long the state-lock is tried within a single grace-cycle.
alluxio.master.standby.heartbeat.interval	2min	The heartbeat interval between Alluxio primary master and standby masters.
alluxio.master.startup.block.integrity.check.enabled	true	Whether the system should be checked on startup for orphaned blocks (blocks having no corresponding files but still taking system resource due to various system failures). Orphaned blocks will be deleted during master startup if this property is true. This property is available since 1.7.1
alluxio.master.tieredstore.global.level0.alias	MEM	The name of the highest storage tier in the entire system.
alluxio.master.tieredstore.global.level1.alias	SSD	The name of the second highest storage tier in the entire system.
alluxio.master.tieredstore.global.level2.alias	HDD	The name of the third highest storage tier in the entire system.
alluxio.master.tieredstore.global.levels	3	The total number of storage tiers in the system.
alluxio.master.tieredstore.global.mediumtype	MEM, SSD, HDD	The list of medium types we support in the system.
alluxio.master.ttl.checker.interval	1hour	How often to periodically check and delete the files with expired ttl value.
alluxio.master.ufs.active.sync.event.rate.interval	60sec	The time interval we use to estimate incoming event rate
alluxio.master.ufs.active.sync.interval	30sec	Time interval to periodically actively sync UFS
alluxio.master.ufs.active.sync.max.activities	10	Max number of changes in a directory to be considered for active syncing
alluxio.master.ufs.active.sync.max.age	10	The maximum number of intervals we will wait to find a quiet period before we have to sync the directories
alluxio.master.ufs.active.sync.poll.batch.size	1024	The number of event batches that should be submitted together to a single thread for processing.
alluxio.master.ufs.active.sync.poll.timeout	10sec	Max time to wait before timing out a polling operation
alluxio.master.ufs.active.sync.retry.timeout	10sec	The max total duration to retry failed active sync operations.A large duration is useful to handle transient failures such as an unresponsive under storage but can lock the inode tree being synced longer.
alluxio.master.ufs.active.sync.thread.pool.size	The number of threads used by the active sync provider process active sync events. A higher number allow the master to use more CPU to process events from an event stream in parallel. If this value is too low, Alluxio may fall behind processing events. Defaults to # of processors / 2	Max number of threads used to perform active sync
alluxio.master.ufs.block.location.cache.capacity	1000000	The capacity of the UFS block locations cache. This cache caches UFS block locations for files that are persisted but not in Alluxio space, so that listing status of these files do not need to repeatedly ask UFS for their block locations. If this is set to 0, the cache will be disabled.
alluxio.master.ufs.path.cache.capacity	100000	The capacity of the UFS path cache. This cache is used to approximate the `ONCE` metadata load behavior (see `alluxio.user.file.metadata.load.type`). Larger caches will consume more memory, but will better approximate the `ONCE` behavior.
alluxio.master.ufs.path.cache.threads	64	The maximum size of the thread pool for asynchronously processing paths for the UFS path cache. Greater number of threads will decrease the amount of staleness in the async cache, but may impact performance. If this is set to 0, the cache will be disabled, and `alluxio.user.file.metadata.load.type=ONCE` will behave like `ALWAYS`.
alluxio.master.unsafe.direct.persist.object.enabled	true	When set to false, writing files using ASYNC_THROUGH or persist CLI with object stores as the UFS will first create temporary objects suffixed by “.alluxio.TIMESTAMP.tmp” in the object store before committed to the final UFS path. When set to true, files will be put to the destination path directly in the object store without staging with a temp suffix. Enabling this optimization by directly persisting files can significantly improve the efficiency writing to object store by making less data copy as rename in object store can be slow, but leaving a short vulnerability window for undefined behavior if a file is written using ASYNC_THROUGH but renamed or removed before the async persist operation completes, while this same file path was reused for other new files in Alluxio.
alluxio.master.update.check.enabled	true	Whether to check for update availability.
alluxio.master.update.check.interval	7day	The interval to check for update availability.
alluxio.master.web.bind.host	0.0.0.0	The hostname Alluxio master web UI binds to.
alluxio.master.web.hostname		The hostname of Alluxio Master web UI.
alluxio.master.web.port	19999	The port Alluxio web UI runs on.
alluxio.master.whitelist	/	A comma-separated list of prefixes of the paths which are cacheable, separated by semi-colons. Alluxio will try to cache the cacheable file when it is read for the first time.
alluxio.master.worker.connect.wait.time	5sec	Alluxio master will wait a period of time after start up for all workers to register, before it starts accepting client requests. This property determines the wait time.
alluxio.master.worker.info.cache.refresh.time	10sec	The worker information list will be refreshed after being cached for this time period. If the refresh time is too big, operations on the job servers or clients may fail because of the stale worker info. If it is too small, continuously updating worker information may case lock contention in the block master
alluxio.master.worker.timeout	5min	Timeout between master and worker indicating a lost worker.

Worker Configuration

The worker configuration specifies information regarding the worker nodes, such as the address and the port number.

Property Name	Default	Description
alluxio.worker.allocator.class	alluxio.worker.block.allocator.MaxFreeAllocator	The strategy that a worker uses to allocate space among storage directories in certain storage layer. Valid options include: `alluxio.worker.block.allocator.MaxFreeAllocator`, `alluxio.worker.block.allocator.GreedyAllocator`, `alluxio.worker.block.allocator.RoundRobinAllocator`.
alluxio.worker.bind.host	0.0.0.0	The hostname Alluxio’s worker node binds to.
alluxio.worker.block.annotator.class	alluxio.worker.block.annotator.LRUAnnotator	The strategy that a worker uses to annotate blocks in order to have an ordered view of them during internalmanagement tasks such as eviction and promotion/demotion. Valid options include: `alluxio.worker.block.annotator.LRFUAnnotator`, `alluxio.worker.block.annotator.LRUAnnotator`,
alluxio.worker.block.annotator.lrfu.attenuation.factor	2.0	A attenuation factor in [2, INF) to control the behavior of LRFU annotator.
alluxio.worker.block.annotator.lrfu.step.factor	0.25	A factor in [0, 1] to control the behavior of LRFU: smaller value makes LRFU more similar to LFU; and larger value makes LRFU closer to LRU.
alluxio.worker.block.heartbeat.interval	1sec	The interval between block workers’ heartbeats to update block status, storage health and other workers’ information to Alluxio Master.
alluxio.worker.block.heartbeat.timeout	${alluxio.worker.master.connect.retry.timeout}	The timeout value of block workers’ heartbeats. If the worker can’t connect to master before this interval expires, the worker will exit.
alluxio.worker.block.master.client.pool.size	11	The block master client pool size on the Alluxio workers.
alluxio.worker.container.hostname		The container hostname if worker is running in a container.
alluxio.worker.data.folder	/alluxioworker/	A relative path within each storage directory used as the data folder for Alluxio worker to put data for tiered store.
alluxio.worker.data.folder.permissions	rwxrwxrwx	The permission set for the worker data folder. If short circuit is used this folder should be accessible by all users (rwxrwxrwx).
alluxio.worker.data.folder.tmp	.tmp_blocks	A relative path in alluxio.worker.data.folder used to store the temporary data for uncommitted files.
alluxio.worker.data.server.class	alluxio.worker.grpc.GrpcDataServer	Selects the networking stack to run the worker with. Valid options are: `alluxio.worker.grpc.GrpcDataServer`.
alluxio.worker.data.server.domain.socket.address		The path to the domain socket. Short-circuit reads make use of a UNIX domain socket when this is set (non-empty). This is a special path in the file system that allows the client and the AlluxioWorker to communicate. You will need to set a path to this socket. The AlluxioWorker needs to be able to create the path. If alluxio.worker.data.server.domain.socket.as.uuid is set, the path should be the home directory for the domain socket. The full path for the domain socket with be {path}/{uuid}.
alluxio.worker.data.server.domain.socket.as.uuid	false	If true, the property alluxio.worker.data.server.domain.socket.addressis the path to the home directory for the domain socket and a unique identifier is used as the domain socket name. If false, the property is the absolute path to the UNIX domain socket.
alluxio.worker.data.tmp.subdir.max	1024	The maximum number of sub-directories allowed to be created in ${alluxio.worker.data.tmp.folder}.
alluxio.worker.evictor.class		The strategy that a worker uses to evict block files when a storage layer runs out of space. Valid options include `alluxio.worker.block.evictor.LRFUEvictor`, `alluxio.worker.block.evictor.GreedyEvictor`, `alluxio.worker.block.evictor.LRUEvictor`, `alluxio.worker.block.evictor.PartialLRUEvictor`.
alluxio.worker.file.buffer.size	1MB	The buffer size for worker to write data into the tiered storage.
alluxio.worker.free.space.timeout	10sec	The duration for which a worker will wait for eviction to make space available for a client write request.
alluxio.worker.hostname		The hostname of Alluxio worker.
alluxio.worker.jvm.monitor.enabled	true	Whether to enable start JVM monitor thread on the worker. This will start a thread to detect JVM-wide pauses induced by GC or other reasons.
alluxio.worker.keytab.file		Kerberos keytab file for Alluxio worker.
alluxio.worker.management.backoff.strategy	ANY	Defines the backoff scope respected by background tasks. Supported values are ANY / DIRECTORY. ANY: Management tasks will backoff from worker when there is any user I/O.This mode will ensure low management task overhead in order to favor immediate user I/O performance. However, making progress on management tasks will require quite periods on the worker.DIRECTORY: Management tasks will backoff from directories with ongoing user I/O.This mode will give better chance of making progress on management tasks.However, immediate user I/O throughput might be reduced due to increased management task activity.
alluxio.worker.management.block.transfer.concurrency.limit	Use {CPU core count}/2 threads block transfer	Puts a limit to how many block transfers are executed concurrently during management.
alluxio.worker.management.load.detection.cool.down.time	10sec	Management tasks will not run for this long after load detected. Any user I/O will still register as a load for this period of time after it is finished. Short durations might cause interference between user I/O and background tier management tasks. Long durations might cause starvation for background tasks.
alluxio.worker.management.task.thread.count	Use {CPU core count} threads for all management tasks	The number of threads for management task executor
alluxio.worker.management.tier.align.enabled	true	Whether to align tiers based on access pattern.
alluxio.worker.management.tier.align.range	100	Maximum number of blocks to consider from one tier for a single alignment task.
alluxio.worker.management.tier.align.reserved.bytes	1GB	The amount of space that is reserved from each storage directory for internal management tasks.
alluxio.worker.management.tier.promote.enabled	true	Whether to promote blocks to higher tiers.
alluxio.worker.management.tier.promote.quota.percent	90	Max percentage of each tier that could be used for promotions. Promotions will be stopped to a tier once its used space go over this value. (0 means never promote, and, 100 means always promote.
alluxio.worker.management.tier.promote.range	100	Maximum number of blocks to consider from one tier for a single promote task.
alluxio.worker.management.tier.swap.restore.enabled	true	Whether to run management swap-restore task when tier alignment cannot make progress.
alluxio.worker.master.connect.retry.timeout	1hour	Retry period before workers give up on connecting to master and exit.
alluxio.worker.master.periodical.rpc.timeout	5min	Timeout for periodical RPC between workers and the leading master. This property is added to prevent workers from hanging in periodical RPCs with previous leading master during flaky network situations. If the timeout is too short, periodical RPCs may not have enough time to get response from the leading master during heavy cluster load and high network latency.
alluxio.worker.network.async.cache.manager.threads.max	8	The maximum number of threads used to cache blocks asynchronously in the data server.
alluxio.worker.network.block.reader.threads.max	2048	The maximum number of threads used to read blocks in the data server.
alluxio.worker.network.block.writer.threads.max	1024	The maximum number of threads used to write blocks in the data server.
alluxio.worker.network.flowcontrol.window	2MB	The HTTP2 flow control window used by worker gRPC connections. Larger value will allow more data to be buffered but will use more memory.
alluxio.worker.network.keepalive.time	30sec	The amount of time for data server (for block reads and block writes) to wait for a response before pinging the client to see if it is still alive.
alluxio.worker.network.keepalive.timeout	30sec	The maximum time for a data server (for block reads and block writes) to wait for a keepalive response before closing the connection.
alluxio.worker.network.max.inbound.message.size	4MB	The max inbound message size used by worker gRPC connections.
alluxio.worker.network.netty.boss.threads	1	How many threads to use for accepting new requests.
alluxio.worker.network.netty.channel	EPOLL	Netty channel type: NIO or EPOLL. If EPOLL is not available, this will automatically fall back to NIO.
alluxio.worker.network.netty.shutdown.quiet.period	2sec	The quiet period. When the netty server is shutting down, it will ensure that no RPCs occur during the quiet period. If an RPC occurs, then the quiet period will restart before shutting down the netty server.
alluxio.worker.network.netty.watermark.high	32KB	Determines how many bytes can be in the write queue before switching to non-writable.
alluxio.worker.network.netty.watermark.low	8KB	Once the high watermark limit is reached, the queue must be flushed down to the low watermark before switching back to writable.
alluxio.worker.network.netty.worker.threads	0	How many threads to use for processing requests. Zero defaults to #cpuCores * 2.
alluxio.worker.network.reader.buffer.size	4MB	When a client reads from a remote worker, the maximum amount of data not received by client allowed before the worker pauses sending more data. If this value is lower than read chunk size, read performance may be impacted as worker waits more often for buffer to free up. Higher value will increase the memory consumed by each read request.
alluxio.worker.network.reader.max.chunk.size.bytes	2MB	When a client read from a remote worker, the maximum chunk size.
alluxio.worker.network.shutdown.timeout	15sec	Maximum amount of time to wait until the worker gRPC server is shutdown (regardless of the quiet period).
alluxio.worker.network.writer.buffer.size.messages	8	When a client writes to a remote worker, the maximum number of data messages to buffer by the server for each request.
alluxio.worker.network.zerocopy.enabled	true	Whether zero copy is enabled on worker when processing data streams.
alluxio.worker.principal		Kerberos principal for Alluxio worker.
alluxio.worker.ramdisk.size	2/3 of total system memory, or 1GB if system memory size cannot be determined	Memory capacity of each worker node.
alluxio.worker.rpc.port	29999	The port for Alluxio worker’s RPC service.
alluxio.worker.session.timeout	1min	Timeout between worker and client connection indicating a lost session connection.
alluxio.worker.storage.checker.enabled	true	Whether periodic storage health checker is enabled on Alluxio workers.
alluxio.worker.tieredstore.block.lock.readers	1000	The max number of concurrent readers for a block lock.
alluxio.worker.tieredstore.block.locks	1000	Total number of block locks for an Alluxio block worker. Larger value leads to finer locking granularity, but uses more space.
alluxio.worker.tieredstore.free.ahead.bytes	0	Amount to free ahead when worker storage is full. Higher values will help decrease CPU utilization under peak storage. Lower values will increase storage utilization.
alluxio.worker.tieredstore.level0.alias	MEM	The alias of the top storage tier on this worker. It must match one of the global storage tiers from the master configuration. We disable placing an alias lower in the global hierarchy before an alias with a higher position on the worker hierarchy. So by default, SSD cannot come before MEM on any worker.
alluxio.worker.tieredstore.level0.dirs.mediumtype	${alluxio.worker.tieredstore.level0.alias}	A list of media types (e.g., “MEM,SSD,SSD”) for each storage directory on the top storage tier specified by alluxio.worker.tieredstore.level0.dirs.path.
alluxio.worker.tieredstore.level0.dirs.path	/mnt/ramdisk on Linux, /Volumes/ramdisk on OSX	The path of storage directory for the top storage tier. Note for MacOS the value should be `/Volumes/`.
alluxio.worker.tieredstore.level0.dirs.quota	${alluxio.worker.ramdisk.size}	The capacity of the top storage tier.
alluxio.worker.tieredstore.level0.watermark.high.ratio	0.95	The high watermark of the space in the top storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.level0.watermark.low.ratio	0.7	The low watermark of the space in the top storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.level1.alias		The alias of the second storage tier on this worker.
alluxio.worker.tieredstore.level1.dirs.mediumtype	${alluxio.worker.tieredstore.level1.alias}	A list of media types (e.g., “MEM,SSD,SSD”) for each storage directory on the second storage tier specified by alluxio.worker.tieredstore.level1.dirs.path.
alluxio.worker.tieredstore.level1.dirs.path		The path of storage directory for the second storage tier.
alluxio.worker.tieredstore.level1.dirs.quota		The capacity of the second storage tier.
alluxio.worker.tieredstore.level1.watermark.high.ratio	0.95	The high watermark of the space in the second storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.level1.watermark.low.ratio	0.7	The low watermark of the space in the second storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.level2.alias		The alias of the third storage tier on this worker.
alluxio.worker.tieredstore.level2.dirs.mediumtype	${alluxio.worker.tieredstore.level2.alias}	A list of media types (e.g., “MEM,SSD,SSD”) for each storage directory on the third storage tier specified by alluxio.worker.tieredstore.level2.dirs.path.
alluxio.worker.tieredstore.level2.dirs.path		The path of storage directory for the third storage tier.
alluxio.worker.tieredstore.level2.dirs.quota		The capacity of the third storage tier.
alluxio.worker.tieredstore.level2.watermark.high.ratio	0.95	The high watermark of the space in the third storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.level2.watermark.low.ratio	0.7	The low watermark of the space in the third storage tier (a value between 0 and 1).
alluxio.worker.tieredstore.levels	1	The number of storage tiers on the worker.
alluxio.worker.ufs.block.open.timeout	5min	Timeout to open a block from UFS.
alluxio.worker.ufs.instream.cache.enabled	true	Enable caching for seekable under storage input stream, so that subsequent seek operations on the same file will reuse the cached input stream. This will improve position read performance as the open operations of some under file system would be expensive. The cached input stream would be stale, when the UFS file is modified without notifying alluxio.
alluxio.worker.ufs.instream.cache.expiration.time	5min	Cached UFS instream expiration time.
alluxio.worker.ufs.instream.cache.max.size	5000	The max entries in the UFS instream cache.
alluxio.worker.web.bind.host	0.0.0.0	The hostname Alluxio worker’s web server binds to.
alluxio.worker.web.hostname		The hostname Alluxio worker’s web UI binds to.
alluxio.worker.web.port	30000	The port Alluxio worker’s web UI runs on.

User Configuration

The user configuration specifies values regarding file system access.

Property Name	Default	Description
alluxio.user.app.id		The custom id to use for labeling this client’s info, such as metrics. If unset, a random long will be used. This value is displayed in the client logs on initialization. Note that using the same app id will cause client info to be aggregated, so different applications must set their own ids or leave this value unset to use a randomly generated id.
alluxio.user.block.avoid.eviction.policy.reserved.size.bytes	0MB	The portion of space reserved in a worker when using the LocalFirstAvoidEvictionPolicy class as block location policy.
alluxio.user.block.master.client.pool.gc.interval	120sec	The interval at which block master client GC checks occur.
alluxio.user.block.master.client.pool.gc.threshold	120sec	A block master client is closed if it has been idle for more than this threshold.
alluxio.user.block.master.client.pool.size.max	10	The maximum number of block master clients cached in the block master client pool.
alluxio.user.block.master.client.pool.size.min	0	The minimum number of block master clients cached in the block master client pool. For long running processes, this should be set to zero.
alluxio.user.block.read.retry.max.duration	2min	N/A
alluxio.user.block.read.retry.sleep.base	250ms	N/A
alluxio.user.block.read.retry.sleep.max	2sec	N/A
alluxio.user.block.remote.read.buffer.size.bytes	8MB	The size of the file buffer to read data from remote Alluxio worker.
alluxio.user.block.size.bytes.default	64MB	Default block size for Alluxio files.
alluxio.user.block.worker.client.pool.gc.threshold	300sec	A block worker client is closed if it has been idle for more than this threshold.
alluxio.user.block.worker.client.pool.max	1024	The maximum number of block worker clients cached in the block worker client pool.
alluxio.user.block.write.location.policy.class	alluxio.client.block.policy.LocalFirstPolicy	The default location policy for choosing workers for writing a file’s blocks.
alluxio.user.client.cache.async.restore.enabled	true	If this is enabled, cache restore state asynchronously.
alluxio.user.client.cache.async.write.enabled	true	If this is enabled, cache data asynchronously.
alluxio.user.client.cache.async.write.threads	16	Number of threads to asynchronously cache data.
alluxio.user.client.cache.dir	/tmp/alluxio_cache	The directory where client-side cache is stored.
alluxio.user.client.cache.enabled	false	If this is enabled, data will be cached on Alluxio client.
alluxio.user.client.cache.evictor.class	alluxio.client.file.cache.evictor.LRUCacheEvictor	The strategy that client uses to evict local cached pages when running out of space. Currently the only valid option provided is `alluxio.client.file.cache.evictor.LRUCacheEvictor`.
alluxio.user.client.cache.evictor.lfu.logbase	2.0	The log base for client cache LFU evictor bucket index.
alluxio.user.client.cache.local.store.file.buckets	1000	The number of file buckets for the local page store of the client-side cache. It is recommended to set this to a high value if the number of unique files is expected to be high (# files / file buckets <= 100,000).
alluxio.user.client.cache.page.size	1MB	Size of each page in client-side cache.
alluxio.user.client.cache.size	512MB	The maximum size of the client-side cache.
alluxio.user.client.cache.store.type	LOCAL	The type of page store to use for client-side cache. Can be either `LOCAL` or `ROCKS`. The `LOCAL` page store stores all pages in a directory, the `ROCKS` page store utilizes rocksDB to persist the data.
alluxio.user.conf.cluster.default.enabled	true	When this property is true, an Alluxio client will load the default values of configuration properties set by Alluxio master.
alluxio.user.conf.sync.interval	1min	The time period of client master heartbeat to update the configuration if necessary from meta master.
alluxio.user.date.format.pattern	MM-dd-yyyy HH:mm:ss:SSS	Display formatted date in cli command and web UI by given date format pattern.
alluxio.user.file.buffer.bytes	8MB	The size of the file buffer to use for file system reads/writes.
alluxio.user.file.copyfromlocal.block.location.policy.class	alluxio.client.block.policy.RoundRobinPolicy	The default location policy for choosing workers for writing a file’s blocks using copyFromLocal command.
alluxio.user.file.create.ttl	-1	Time to live for files created by a user, no ttl by default.
alluxio.user.file.create.ttl.action	DELETE	When file’s ttl is expired, the action performs on it. Options: DELETE (default) or FREE
alluxio.user.file.delete.unchecked	false	Whether to check if the UFS contents are in sync with Alluxio before attempting to delete persisted directories recursively.
alluxio.user.file.master.client.pool.gc.interval	120sec	The interval at which file system master client GC checks occur.
alluxio.user.file.master.client.pool.gc.threshold	120sec	A fs master client is closed if it has been idle for more than this threshold.
alluxio.user.file.master.client.pool.size.max	10	The maximum number of fs master clients cached in the fs master client pool.
alluxio.user.file.master.client.pool.size.min	0	The minimum number of fs master clients cached in the fs master client pool. For long running processes, this should be set to zero.
alluxio.user.file.metadata.load.type	ONCE	The behavior of loading metadata from UFS. When information about a path is requested and the path does not exist in Alluxio, metadata can be loaded from the UFS. Valid options are `ALWAYS`, `NEVER`, and `ONCE`. `ALWAYS` will always access UFS to see if the path exists in the UFS. `NEVER` will never consult the UFS. `ONCE` will access the UFS the “first” time (according to a cache), but not after that. This parameter is ignored if a metadata sync is performed, via the parameter “alluxio.user.file.metadata.sync.interval”
alluxio.user.file.metadata.sync.interval	-1	The interval for syncing UFS metadata before invoking an operation on a path. -1 means no sync will occur. 0 means Alluxio will always sync the metadata of the path before an operation. If you specify a time interval, Alluxio will (best effort) not re-sync a path within that time interval. Syncing the metadata for a path must interact with the UFS, so it is an expensive operation. If a sync is performed for an operation, the configuration of “alluxio.user.file.metadata.load.type” will be ignored.
alluxio.user.file.passive.cache.enabled	true	Whether to cache files to local Alluxio workers when the files are read from remote workers (not UFS).
alluxio.user.file.persist.on.rename	false	Whether or not to asynchronously persist any files which have been renamed. This is helpful when working with compute frameworks which use rename to commit results.
alluxio.user.file.persistence.initial.wait.time	0	Time to wait before starting the persistence job. When the value is set to -1, the file will be persisted by rename operation or persist CLI but will not be automatically persisted in other cases. This is to avoid the heavy object copy in rename operation when alluxio.user.file.writetype.default is set to ASYNC_THROUGH. This value should be smaller than the value of alluxio.master.persistence.max.total.wait.time
alluxio.user.file.readtype.default	CACHE	Default read type when creating Alluxio files. Valid options are `CACHE_PROMOTE` (move data to highest tier if already in Alluxio storage, write data into highest tier of local Alluxio if data needs to be read from under storage), `CACHE` (write data into highest tier of local Alluxio if data needs to be read from under storage), `NO_CACHE` (no data interaction with Alluxio, if the read is from Alluxio data migration or eviction will not occur).
alluxio.user.file.replication.durable	1	The target replication level of a file created by ASYNC_THROUGH writesbefore this file is persisted.
alluxio.user.file.replication.max	-1	The target max replication level of a file in Alluxio space. Setting this property to a negative value means no upper limit.
alluxio.user.file.replication.min	0	The target min replication level of a file in Alluxio space.
alluxio.user.file.reserved.bytes	${alluxio.user.block.size.bytes.default}	The size to reserve on workers for file system writes.Using smaller value will improve concurrency for writes smaller than block size.
alluxio.user.file.sequential.pread.threshold	2MB	An upper bound on the client buffer size for positioned read to hint at the sequential nature of reads. For reads with a buffer size greater than this threshold, the read op is treated to be sequential and the worker may handle the read differently. For instance, cold reads from the HDFS ufs may use a different HDFS client API.
alluxio.user.file.target.media		Preferred media type while storing file’s blocks.
alluxio.user.file.ufs.tier.enabled	false	When workers run out of available memory, whether the client can skip writing data to Alluxio but fallback to write to UFS without stopping the application. This property only works when the write type is ASYNC_THROUGH.
alluxio.user.file.waitcompleted.poll	1sec	The time interval to poll a file for its completion status when using waitCompleted.
alluxio.user.file.write.tier.default	0	The default tier for choosing a where to write a block. Valid option is any integer. Non-negative values identify tiers starting from top going down (0 identifies the first tier, 1 identifies the second tier, and so on). If the provided value is greater than the number of tiers, it identifies the last tier. Negative values identify tiers starting from the bottom going up (-1 identifies the last tier, -2 identifies the second to last tier, and so on). If the absolute value of the provided value is greater than the number of tiers, it identifies the first tier.
alluxio.user.file.writetype.default	ASYNC_THROUGH	Default write type when creating Alluxio files. Valid options are `MUST_CACHE` (write will only go to Alluxio and must be stored in Alluxio), `CACHE_THROUGH` (try to cache, write to UnderFS synchronously), `THROUGH` (no cache, write to UnderFS synchronously), `ASYNC_THROUGH` (write to cache, write to UnderFS asynchronously, replicated alluxio.user.file.replication.durable times in Alluxio before data is persisted.
alluxio.user.hostname		The hostname to use for an Alluxio client.
alluxio.user.local.reader.chunk.size.bytes	8MB	When a client reads from a local worker, the maximum data chunk size.
alluxio.user.local.writer.chunk.size.bytes	64KB	When a client writes to a local worker, the maximum data chunk size.
alluxio.user.logging.threshold	10s	Logging a client RPC when it takes more time than the threshold.
alluxio.user.logs.dir	${alluxio.logs.dir}/user	The path to store logs of Alluxio shell. To change its value, one can set environment variable $ALLUXIO_USER_LOGS_DIR. Note: overwriting this property will only work when it is passed as a JVM system property (e.g., appending “-Dalluxio.user.logs.dir”=<NEW_VALUE>” to $ALLUXIO_JAVA_OPTS). Setting it in alluxio-site.properties will not work.
alluxio.user.master.polling.timeout	30sec	The maximum time for a rpc client to wait for master to respond.
alluxio.user.metadata.cache.enabled	false	If this is enabled, metadata of paths will be cached. The cached metadata will be evicted when it expires after alluxio.user.metadata.cache.expiration.time or the cache size is over the limit of alluxio.user.metadata.cache.max.size.
alluxio.user.metadata.cache.expiration.time	10min	Metadata will expire and be evicted after being cached for this time period. Only valid if the filesystem is alluxio.client.file.MetadataCachingBaseFileSystem.
alluxio.user.metadata.cache.max.size	100000	Maximum number of paths with cached metadata. Only valid if the filesystem is alluxio.client.file.MetadataCachingBaseFileSystem.
alluxio.user.metrics.collection.enabled	false	Enable collecting the client-side metrics and heartbeat them to master
alluxio.user.metrics.heartbeat.interval	10sec	The time period of client master heartbeat to send the client-side metrics.
alluxio.user.network.data.timeout		The maximum time for an Alluxio client to wait for a data response (e.g. block reads and block writes) from Alluxio worker.
alluxio.user.network.flowcontrol.window		The HTTP2 flow control window used by user gRPC connections. Larger value will allow more data to be buffered but will use more memory.
alluxio.user.network.keepalive.time		The amount of time for a gRPC client (for block reads and block writes) to wait for a response before pinging the server to see if it is still alive.
alluxio.user.network.keepalive.timeout		The maximum time for a gRPC client (for block reads and block writes) to wait for a keepalive response before closing the connection.
alluxio.user.network.max.inbound.message.size		The max inbound message size used by user gRPC connections.
alluxio.user.network.netty.channel		Type of netty channels. If EPOLL is not available, this will automatically fall back to NIO.
alluxio.user.network.netty.worker.threads		How many threads to use for remote block worker client to read from remote block workers.
alluxio.user.network.reader.buffer.size.messages		When a client reads from a remote worker, the maximum number of messages to buffer by the client. A message can be either a command response, a data chunk, or a gRPC stream event such as complete or error.
alluxio.user.network.reader.chunk.size.bytes		When a client reads from a remote worker, the maximum chunk size.
alluxio.user.network.rpc.flowcontrol.window	2MB	The HTTP2 flow control window used by user rpc connections. Larger value will allow more data to be buffered but will use more memory.
alluxio.user.network.rpc.keepalive.time	9223372036854775807	The amount of time for a rpc client to wait for a response before pinging the server to see if it is still alive.
alluxio.user.network.rpc.keepalive.timeout	30sec	The maximum time for a rpc client to wait for a keepalive response before closing the connection.
alluxio.user.network.rpc.max.connections	1	The maximum number of physical connections to be used per target host.
alluxio.user.network.rpc.max.inbound.message.size	100MB	The max inbound message size used by user rpc connections.
alluxio.user.network.rpc.netty.channel	EPOLL	Type of netty channels used by rpc connections. If EPOLL is not available, this will automatically fall back to NIO.
alluxio.user.network.rpc.netty.worker.threads	0	How many threads to use for rpc client to read from remote workers.
alluxio.user.network.streaming.flowcontrol.window	2MB	The HTTP2 flow control window used by user streaming connections. Larger value will allow more data to be buffered but will use more memory.
alluxio.user.network.streaming.keepalive.time	9223372036854775807	The amount of time for a streaming client to wait for a response before pinging the server to see if it is still alive.
alluxio.user.network.streaming.keepalive.timeout	30sec	The maximum time for a streaming client to wait for a keepalive response before closing the connection.
alluxio.user.network.streaming.max.connections	64	The maximum number of physical connections to be used per target host.
alluxio.user.network.streaming.max.inbound.message.size	100MB	The max inbound message size used by user streaming connections.
alluxio.user.network.streaming.netty.channel	EPOLL	Type of netty channels used by streaming connections. If EPOLL is not available, this will automatically fall back to NIO.
alluxio.user.network.streaming.netty.worker.threads	0	How many threads to use for streaming client to read from remote workers.
alluxio.user.network.writer.buffer.size.messages		When a client writes to a remote worker, the maximum number of messages to buffer by the client. A message can be either a command response, a data chunk, or a gRPC stream event such as complete or error.
alluxio.user.network.writer.chunk.size.bytes		When a client writes to a remote worker, the maximum chunk size.
alluxio.user.network.writer.close.timeout		The timeout to close a writer client.
alluxio.user.network.writer.flush.timeout		The timeout to wait for flush to finish in a data writer.
alluxio.user.network.zerocopy.enabled		Whether zero copy is enabled on client when processing data streams.
alluxio.user.rpc.retry.base.sleep	50ms	Alluxio client RPCs automatically retry for transient errors with an exponential backoff. This property determines the base time in the exponential backoff.
alluxio.user.rpc.retry.max.duration	2min	Alluxio client RPCs automatically retry for transient errors with an exponential backoff. This property determines the maximum duration to retry for before giving up. Note that, this value is set to 5s for fs and fsadmin CLIs.
alluxio.user.rpc.retry.max.sleep	3sec	Alluxio client RPCs automatically retry for transient errors with an exponential backoff. This property determines the maximum wait time in the backoff.
alluxio.user.short.circuit.enabled	true	The short circuit read/write which allows the clients to read/write data without going through Alluxio workers if the data is local is enabled if set to true.
alluxio.user.short.circuit.preferred	false	When short circuit and domain socket both enabled, prefer to use short circuit.
alluxio.user.streaming.data.read.timeout	1h	The maximum time for an Alluxio client to wait for a data response for read requests from Alluxio worker. Keep in mind that some streaming operations may take an unexpectedly long time, such as UFS io. In order to handle occasional slow operations, it is recommended for this parameter to be set to a large value, to avoid spurious timeouts.
alluxio.user.streaming.data.write.timeout	1h	The maximum time for an Alluxio client to wait for when writing 1 chunk for block writes to an Alluxio worker. This value can be tuned to offset instability from the UFS.
alluxio.user.streaming.reader.buffer.size.messages	16	When a client reads from a remote worker, the maximum number of messages to buffer by the client. A message can be either a command response, a data chunk, or a gRPC stream event such as complete or error.
alluxio.user.streaming.reader.chunk.size.bytes	1MB	When a client reads from a remote worker, the maximum chunk size.
alluxio.user.streaming.writer.buffer.size.messages	16	When a client writes to a remote worker, the maximum number of messages to buffer by the client. A message can be either a command response, a data chunk, or a gRPC stream event such as complete or error.
alluxio.user.streaming.writer.chunk.size.bytes	1MB	When a client writes to a remote worker, the maximum chunk size.
alluxio.user.streaming.writer.close.timeout	30min	The timeout to close a writer client.
alluxio.user.streaming.writer.flush.timeout	30min	The timeout to wait for flush to finish in a data writer.
alluxio.user.streaming.zerocopy.enabled	true	Whether zero copy is enabled on client when processing data streams.
alluxio.user.ufs.block.location.all.fallback.enabled	true	Whether to return all workers as block location if ufs block locations are not co-located with any Alluxio workers or is empty.
alluxio.user.ufs.block.read.concurrency.max	2147483647	The maximum concurrent readers for one UFS block on one Block Worker.
alluxio.user.ufs.block.read.location.policy	alluxio.client.block.policy.LocalFirstPolicy	When an Alluxio client reads a file from the UFS, it delegates the read to an Alluxio worker. The client uses this policy to choose which worker to read through. Built-in choices: [<a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/DeterministicHashPolicy.html">alluxio.client.block.policy.DeterministicHashPolicy</a>, <a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/LocalFirstAvoidEvictionPolicy.html">alluxio.client.block.policy.LocalFirstAvoidEvictionPolicy</a>, <a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/LocalFirstPolicy.html">alluxio.client.block.policy.LocalFirstPolicy</a>, <a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/MostAvailableFirstPolicy.html">alluxio.client.block.policy.MostAvailableFirstPolicy</a>, <a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/RoundRobinPolicy.html">alluxio.client.block.policy.RoundRobinPolicy</a>, <a href=”https://docs.alluxio.io/os/javadoc/edge/alluxio/client/block/policy/SpecificHostPolicy.html">alluxio.client.block.policy.SpecificHostPolicy</a>].
alluxio.user.ufs.block.read.location.policy.deterministic.hash.shards	1	When alluxio.user.ufs.block.read.location.policy is set to alluxio.client.block.policy.DeterministicHashPolicy, this specifies the number of hash shards.
alluxio.user.worker.list.refresh.interval	2min	The interval used to refresh the live worker list on the client

Resource Manager Configuration

When running Alluxio with resource managers like Mesos and YARN, Alluxio has additional configuration options.

Property Name	Default	Description
alluxio.integration.master.resource.cpu	1	The number of CPUs to run an Alluxio master for YARN framework.
alluxio.integration.master.resource.mem	1024MB	The amount of memory to run an Alluxio master for YARN framework.
alluxio.integration.worker.resource.cpu	1	The number of CPUs to run an Alluxio worker for YARN framework.
alluxio.integration.worker.resource.mem	1024MB	The amount of memory to run an Alluxio worker for YARN framework.
alluxio.integration.yarn.workers.per.host.max	1	The number of workers to run on an Alluxio host for YARN framework.

Security Configuration

The security configuration specifies information regarding the security features, such as authentication and file permission. Settings for authentication take effect for master, worker, and user. Settings for file permission only take effect for master. See Security for more information about security features.

Property Name	Default	Description
alluxio.security.authentication.custom.provider.class		The class to provide customized authentication implementation, when alluxio.security.authentication.type is set to CUSTOM. It must implement the interface ‘alluxio.security.authentication.AuthenticationProvider’.
alluxio.security.authentication.type	SIMPLE	The authentication mode. Currently three modes are supported: NOSASL, SIMPLE, CUSTOM. The default value SIMPLE indicates that a simple authentication is enabled. Server trusts whoever the client claims to be.
alluxio.security.authorization.permission.enabled	true	Whether to enable access control based on file permission.
alluxio.security.authorization.permission.supergroup	supergroup	The super group of Alluxio file system. All users in this group have super permission.
alluxio.security.authorization.permission.umask	022	The umask of creating file and directory. The initial creation permission is 777, and the difference between directory and file is 111. So for default umask value 022, the created directory has permission 755 and file has permission 644.
alluxio.security.group.mapping.cache.timeout	1min	Time for cached group mapping to expire.
alluxio.security.group.mapping.class	alluxio.security.group.provider.ShellBasedUnixGroupsMapping	The class to provide user-to-groups mapping service. Master could get the various group memberships of a given user. It must implement the interface ‘alluxio.security.group.GroupMappingService’. The default implementation execute the ‘groups’ shell command to fetch the group memberships of a given user.
alluxio.security.login.impersonation.username	HDFS_USER	When alluxio.security.authentication.type is set to SIMPLE or CUSTOM, user application uses this property to indicate the IMPERSONATED user requesting Alluxio service. If it is not set explicitly, or set to NONE, impersonation will not be used. A special value of ‘HDFS_USER‘ can be specified to impersonate the hadoop client user.
alluxio.security.login.username		When alluxio.security.authentication.type is set to SIMPLE or CUSTOM, user application uses this property to indicate the user requesting Alluxio service. If it is not set explicitly, the OS login user will be used.
alluxio.security.stale.channel.purge.interval	3day	Interval for which client channels that have been inactive will be regarded as unauthenticated. Such channels will reauthenticate with their target master upon being used for new RPCs.