Re: 2.5.65-mm2

Steven P. Cole
2003-03-19T21:55:08Z

On Wed, 2003-03-19 at 13:57, Steven P. Cole wrote:
> On Wed, 2003-03-19 at 13:10, Andrew Morton wrote:
> > Steven Cole <elenstev@mesatop.com> wrote:
> > >
> > > On Wed, 2003-03-19 at 02:21, Andrew Morton wrote:
> > > >
> > > > http://www.zip.com.au/~akpm/linux/patches/2.5/2.5.65/2.5.65-mm2/
> > > >
> > >
> > > I am seeing a significant degradation of interactivity under load with
> > > recent -mm kernels. The load is dbench on a reiserfs file system with
> > > increasing numbers of clients. The test machine is single PIII, IDE,
> > > 256MB memory, all kernels PREEMPT.
> >
> > (This email brought to you while running dbench 128 on ext3)
> >
> > There's a pretty big reiserfs patch in -mm. Are you able to whip up
> > an ext2 partition and see if that displays the same problem?
> >
>
> I repeated the test on an ext3 partition, and the response with 28
> dbench clients running is definitely better, although I'm starting to
> get some stalls of a couple seconds while typing this in Evolution on
> the machine under test. Now it's becoming intolerable, so I aborted the
> dbench run so I could finish this email.
>
> This was with 2.5.65-mm2 and elevator=as. I'll repeat soon with
> elevator=deadline. I didn't try typing in Evolution with 2.5.65-bk
> under high loads, so I'll also give that a try.
>
> Summary: using ext3, the simple window shake and scrollbar wiggle tests
> were much improved, but really using Evolution left much to be desired.

Replying to myself for a followup,

I repeated the tests with 2.5.65-mm2 elevator=deadline and the situation
was similar to elevator=as. Running dbench on ext3, the response to
desktop switches and window wiggles was improved over running dbench on
reiserfs, but typing in Evolution was subject to long delays with dbench
clients greater than 16.

I rebooted with 2.5.65-bk and ran dbench on ext3 again. Everything was
going smoothly, excellent interactivity, and then with dbench 28, the
system froze. No response to pings, no response to alt-sysrq-b (after
alt-sysrq-s). A hard reset was required. Nothing interesting logged.
Too bad. Before it crashed, 2.5.65-bk was responding to typing in an
Evolution new message window better than -mm2.

I'll see if this is repeatable.

Steven