On Mon, 30 Apr 2007 20:14:05 +0200 "Jiri Slaby" <[EMAIL PROTECTED]> wrote:
> > > I have a problem with higher disk loads (e.g. running git-log or yum > > > update). > > > Many processes end up in D state and system is unusable -- I'm not able > > > to run > > > anything but smooth mouse moving when this happens. > > > > > > If I wait for a 20-30sec it becomes usable. This happens in > > > 2.6.21-rc7-mm2 and > > > also in 2007-04-28-05-06 broken-out snapshot. I think 2.6.21-rc6-mm1 > > > worked > > > fine, but I'm uncertain. If it is important, let me know to re-test. > > > > > > > It is important, but I doubt if retesting 2.6.21-rc6-mm1 will clarify > > things a lot. > > > > Could you try switching to a different IO scheduler please? Anticipatory > > would suit. > > As I wrote below the sysrq-t, switch to noop didn't help, but it seems > that it's harder to reproduce with that: > > <cite it's_bad_to_write_anything_below_logs="true"> > Note that yum works on lvm on raid0 and git too, but on the another md volume. > Both ext3s. Drivers are sata_promise and ata_piix (sata disk); CFQ scheduler. > Using noop is no change (but seems to be harder to reproduce with it). I > figured > out that it probably happens when 2+ processes are on both "processors" (HT on > P4) and are IO wait (multiload-applet shows red above the half). > > Swap usage is 0 all the time. > </cite> My comprehension skills on Monday morning are even less than usual ;) I would check the anticipatory scheduler as well, please. I don't know what no-op would do with a workload like that, but it probably isn't very good. You appear to believe that it's related to the CPU scheduler? That's a bit unexpected - it sounds more like a VFS/IO thing? But stranger things have happened. I guess it's time to end the staircase experiment in -mm. http://userweb.kernel.org/~akpm/js.bz2 is my current rollup (against 2.6.21) minus staircase and related things. Pretty please. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
