System Configuration

AttentionThis page documents an earlier version. Go to the latest (v2.1)version.

Do the following configuration steps on each of the nodes in the cluster.

ntp

If your instance does not have public Internet access, make sure the following packages have been installed (all can be retrieved from the yum repo epel, make sure to use the latest epel release repo):

  • epel-release
  • ntp

Here’s the command to install these packages.

  1. $ sudo yum install -y epel-release ntp

Setting ulimits

In Linux, ulimit is used to limit and control the usage of system resources (threads, files, and network connections) on a per-process or per-user basis.

Checking ulimits

Run the following command to check the ulimit settings.

  1. $ ulimit -a

The following settings are recommended when running YugabyteDB.

  1. core file size          (blocks, -c) unlimited
  2. data seg size           (kbytes, -d) unlimited
  3. scheduling priority             (-e) 0
  4. file size               (blocks, -f) unlimited
  5. pending signals                 (-i) 119934
  6. max locked memory       (kbytes, -l) 64
  7. max memory size         (kbytes, -m) unlimited
  8. open files                      (-n) 1048576
  9. pipe size            (512 bytes, -p) 8
  10. POSIX message queues     (bytes, -q) 819200
  11. real-time priority              (-r) 0
  12. stack size              (kbytes, -s) 8192
  13. cpu time               (seconds, -t) unlimited
  14. max user processes              (-u) 12000
  15. virtual memory          (kbytes, -v) unlimited
  16. file locks                      (-x) unlimited

Setting system-wide ulimits

You can change values by substituting the -n option for any possible value in the output of ulimit -a. Issue a command in the following form to change a ulimit setting.

  1. $ ulimit -n <value>
  1. -f (file size): unlimited
  2. -t (cpu time): unlimited
  3. -v (virtual memory): unlimited [1]
  4. -l (locked-in-memory size): unlimited
  5. -n (open files): 64000
  6. -m (memory size): unlimited [1] [2]
  7. -u (processes/threads): 64000

Note

  • After changing a ulimit setting, the YB-Master and YB-TServer processes must be restarted in order for the new settings to take effect. Check the /proc/<process pid> file to see the current settings.
  • Changes made using ulimit may revert following a system restart depending on the system configuration.