Re: Feedback on preemptible kernel patch xfs

[Robert Love <rml@tech9.net>]

On Fri, 2001-09-21 at 08:29, Gerold Jury wrote:
> On Thursday 20 September 2001 02:56, Robert Love wrote:
> > I am surprised, you should see a difference, especially with the
> > latencytest.  Silly question, but you both applied the patch and enabled
> > the config statement, right?
> >
> Really, i have checked twice.
> The patch could, by the way, write a line to the syslog when enabled.

OK, I believe you :)

Yes, but I find all the `NET4.0 loaded!' as crap as it is.  If
CONFIG_PREEMPT is defined, rest assured the code is correct.

> All the filesystem operations happend on the xfs partitions.
> I noticed more equally distributed read/write operations with smaller slices 
> during big copy jobs on xfs.
> This effect may well come from the preemption patch. I used a spare partition
> for the test, so the filesystem was in the same state with both kernels 
> during the tests.
> Xfs usually delays the write operations and does them in bigger blocks.
> The behavior of XFS has changed with the kernel versions towards this 
> direction anyway but is clearly different with the preemption patch.
> 
> I will redo the latency tests with the standard Xfree86 nvidia driver.
> It may give a different picture.
> The graphics test and the /proc test have shown the highest latency's.
> Both involve the xserver (proc for the xterm).
> The other tests have been around 5-6 msec in both cases.
> 
> And i will do the dbench test of course.

Very good. Please let me know.

-- 
Robert M. Love
rml at ufl.edu
rml at tech9.net