Re: [patch v4 0/3] aio: implement request batching [more performance numbers]

[Jeff Moyer <jmoyer@redhat.com>]

Jens Axboe <jens.axboe@oracle.com> writes:

> So here's a pretty basic test. It does random reads from a bunch of
> devices, I tested both 4kb and 64kb block sizes. Queue depth used is 32
> for both cases, but note that this test uses a thread per device (so the
> queue depth is 32 per device). Results are averaged over 3 runs.
> slat/clat are the submission and completion latencies, they are in
> microseconds here.
>
> 4kb random reads
>
> kernel               sys     IOPS       slat    clat
> ----------------------------------------------------
> 2.6.32-rc3+patch    25.8%   192500      7.9     2606
> 2.6.32-rc3          27.4%   191300      8.4     2612
>
>
>
> 64kb random reads
>
> kernel               sys     IOPS       slat    clat
> ----------------------------------------------------
> 2.6.32-rc3+patch     2.5%    24590      9.7     9681
> 2.6.32-rc3           2.5%    24580      9.4     9691
>
> So pretty close, nothing earth shattering here. What the results above
> do not show is that the 4kb test runs very stable with your patch.
> Mainline fluctuates somewhat in the bandwidth, most likely due to the
> varying depth.

OK, good news.  Thanks for testing!

Cheers,
Jeff