zfs very poor performance compared to ufs due to lack of cache?
jhell at DataIX.net
Sun Sep 5 23:34:34 UTC 2010
On 09/05/2010 16:13, Steven Hartland wrote:
>> 3656: uint64_t available_memory = ptoa((uintmax_t)cnt.v_free_count
>> 3657: + cnt.v_cache_count);
> earlier at 3614 I have what I think your after which is:
> uint64_t available_memory = ptoa((uintmax_t)cnt.v_free_count);
Alright change this to the above, recompile and re-run your tests.
Effectively before this change that apparently still needs to be MFC'd
or MFS'd would not allow ZFS to look at or use cnt.v_cache_count. Pretty
much to sum it up "available mem = cache + free"
This possibly could cause what your seeing but there might be other
changes still yet TBD. Ill look into what else has changed from RELEASE
Also do you check out your sources with svn(1) or csup(1) ?
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