[SoftNAS KB]: ZFS atime Configuration

Symptoms

 If you are noting slow performance in your instance, this performance tweak may be of help. With this configuration, common Web Server applications accessing SoftNAS shares will not need to keep account of Access Times.

Purpose

To improve kernel workload, you can set your instance so that common web server applications do not need to keep track of access times. Setting the 'atime' ZFS attribute to 'off' alleviates the need for the kernel to update the access time of a file each time it is requested, and less work in the kernel means more cycles are available for serving content.

Resolution

To List ALL attributes for a pool, as sudo:

zfs get all <POOL>

This will output all the attributes for the pool.

# zfs set atime=off <POOL>

This will set the 'atime' off for the entire <POOL>.

If you wish to set 'atime' off for only single volume for some special cases, replace <POOL> with <POOL/VOLUME>.