Differences between revisions 11 and 12
Revision 11 as of 2007-06-20T21:42:39+0000
Size: 848
Editor: IvanVoras
Comment: Increase arc_max to 80 MB
Revision 12 as of 2007-07-30T20:39:43+0000
Size: 1026
Editor: IvanVoras
Comment: Separate zil_disable to separate < 1 GB section and add recommendation for kern.maxvnodes
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 * vfs.zfs.zil_disable="1" (loader.conf)
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On machines with less than 1 GB memory, some options to try are:

 * vfs.zfs.zil_disable="1" (loader.conf)
 * For 512 MB, reduce kern.maxvnodes and vfs.zfs.arc_max to half their value, for 256 MB, to quarter, etc.

ZFS Tuning Guide

(Work in Progress)

To use ZFS 1GB of memory is recommended but, more is helpful as ZFS does lots of caching. A amd64 system is preferred due to the larger address space.

amd64

On amd64 it helps to crank kern.maxvnodes way up if you have the RAM for it (e.g. 400000 for a 2GB system). Keep an eye on vfs.numvnodes during production to see where it stabilizes.

i386

Minimum recommended memory: 1 GB

Even on machines with enough memory, several configuration knobs need to be altered to ensure stable operation. Here's an example configuration for a machine with 1 GB memory:

  • kern.maxvnodes="50000" (sysctl)
  • vfs.zfs.prefetch_disable="1" (loader.conf)
  • vfs.zfs.arc_max="83886080" (loader.conf)
  • vm.kmem_size_max="268435456" (loader.conf)

On machines with less than 1 GB memory, some options to try are:

  • vfs.zfs.zil_disable="1" (loader.conf)
  • For 512 MB, reduce kern.maxvnodes and vfs.zfs.arc_max to half their value, for 256 MB, to quarter, etc.

ZFSTuningGuide (last edited 2023-04-02T17:15:08+0000 by GrahamPerrin)