NFS server bottlenecks

[Nikolay Denev]

On Oct 18, 2012, at 6:11 PM, Nikolay Denev <ndenev at gmail.com> wrote:

> 
> On Oct 15, 2012, at 5:34 PM, Ivan Voras <ivoras at freebsd.org> wrote:
> 
>> On 15 October 2012 16:31, Nikolay Denev <ndenev at gmail.com> wrote:
>>> 
>>> On Oct 15, 2012, at 2:52 PM, Ivan Voras <ivoras at freebsd.org> wrote:
>> 
>>>> http://people.freebsd.org/~ivoras/diffs/nfscache_lock.patch
>>>> 
>>>> It should apply to HEAD without Rick's patches.
>>>> 
>>>> It's a bit different approach than Rick's, breaking down locks even more.
>>> 
>>> Applied and compiled OK, I will be able to test it tomorrow.
>> 
>> Ok, thanks!
>> 
>> The differences should be most visible in edge cases with a larger
>> number of nfsd processes (16+) and many CPU cores.
> 
> I'm now rebooting with your patch, and hopefully will have some results tomorrow.
> 

Here are the results from testing both patches : http://home.totalterror.net/freebsd/nfstest/results.html
Both tests ran for about 14 hours ( a bit too much, but I wanted to compare different zfs recordsize settings ),
and were done first after a fresh reboot.
The only noticeable difference seems to be much more context switches with Ivan's patch.