Compression

Since im using ZFS as storage via NFS for my some of my vmware environments i need to ensure that latency on my disk is reduced where ever possible.

There is alot of talk about ZFS compression being “faster” than a non-compressed pool due to less physical data being pulled off the drives. This of course depends on the system powering ZFS, but i wanted to run some tests specifically on latency. Throughput is fine in some situations, but latency is a killer when it comes to lots of small reads and writes (in the case of hosting virtual machines)

ZFS compression as of OpenSolaris 2008.11 has a few types to choose from.

lzjb (default) | gzip | gzip-[1-9]

They are used via the zfs set compression=gzip poolname command.

The following test was quickly done out of personal interest - and is in no way scientific!

I have a AMD cpu with 3 cores (2.4Ghz). The data i copied to each of the shares consisted of video / documents / pictures and music. The first test i have done is based on compression only (i have not measured throughput)