lkml.org 
[lkml]   [2007]   [Nov]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch] Give kjournald a IOPRIO_CLASS_RT io priority
On Nov 16, 2007 8:25 AM, Alan D. Brunelle <alan.brunelle@hp.com> wrote:
> Here are the results for the latest tests, some notes:
>
> o The machine actually has 8GiB of RAM, so the tests still may end up
> using (some) page cache. (But at least it was the same for both kernels!
> :-) )
>
> o Sorry the results took so long - the updated tree size caused the
> runs to take > 12 hours...
>
> o The longer runs seemed to bring down the standard deviation a bit,
> although they are still quite large.
>
> o 10 runs per test (read large file, read a tree, overwrite large
> file), with averages presented.
>
> o 1st 4 columns (min, avg, max, std dev) refer to the average run
> lengths for the tests - real time, in seconds
>
> o The last 3 columns are extracted from iostat results over the course
> of the whole run.
>
> o The read a tree test certainly stands out - the other 2 large file
> manipulations have the two kernels within a couple of percent, but the
> read a tree test has Arjan's patch taking about 47%(!) longer on
> average. The increased %iowait & %system time in all 3 cases is interesting.
>
>
> Read large file:
>
> Kernel Min Avg Max Std Dev %user %system %iowait
> --------------------------------------------------------------
> base : 201.6 215.1 275.5 22.8 0.26% 4.69% 33.54%
> arjan: 198.0 210.3 261.5 18.5 0.33% 10.24% 54.00%
>
> Read a tree:
>
> Kernel Min Avg Max Std Dev %user %system %iowait
> --------------------------------------------------------------
> base : 3518.2 4631.3 5991.3 784.6 0.19% 3.29% 23.56%
> arjan: 5731.6 6849.8 7777.4 731.6 0.32% 9.90% 52.70%
>
> Overwrite large file:
>
> Kernel Min Avg Max Std Dev %user %system %iowait
> --------------------------------------------------------------
> base : 104.2 147.7 239.5 38.4 0.02% 0.05% 1.08%
> arjan: 106.2 149.7 239.2 38.4 0.25% 0.79% 14.97%
>
> Let me know if there is anything else I can do to elaborate, or if you
> have suggestions for further testing.

Out of curiosity, what are the mount options for the freshly created
ext3 fs? In particular, are you using noatime, nodiratime?

Ray
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-11-16 19:39    [from the cache]
©2003-2011 Jasper Spaans