lkml.org 
[lkml]   [2008]   [Jun]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [BUGFIX][RESEND] Fix the starving writes bug in the anticipatory IO scheduler
On Mon, 16 Jun 2008, Nick Piggin wrote:

> Well, thanks for the report and test case. I'm a bit out of the
> loop when it comes to IO scheduling these days, however the fix
> seems good to me.
>
> Does google still use AS scheduling? This doesn't introduce any
> performance regressions that you can tell?

Yes we use AS scheduler. Benchmarking results on workloads have shown that
AS does as good a job (and better in some cases) as CFQ. When there is
a single thread reading/writing to disk, AS performs as well as CFQ. With
multiple threads doing IO such that there are a lot of outstanding
requests, CFQ performs worse than AS in terms of throughput.

-Divyesh.


\
 
 \ /
  Last update: 2008-06-17 03:03    [W:0.039 / U:0.096 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site