More zfs benchmarks

Jonathan Belson jon at
Sun Feb 14 20:26:21 UTC 2010

On 14 Feb 2010, at 19:13, Artem Belevich wrote:
> Can you check if kstat.zfs.misc.arcstats.memory_throttle_count sysctl
> increments during your tests?
> ZFS self-throttles writes if it thinks system is running low on
> memory. Unfortunately on FreeBSD the 'free' list is a *very*
> conservative indication of available memory so ZFS often starts
> throttling before it's really needed. With only 2GB in the system,
> that's probably what slows you down.

I tested a number of times during a 2GB write to a zfs partition and the count stayed at 0.



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