[issue1556] many processes stuck in "hmrrcm", system unusable

[Steve O'Hara-Smith]

On Mon, 5 Oct 2009 08:49:59 +0300
Hasso Tepper <hasso at estpak.ee> wrote:

> Steve O'Hara-Smith wrote:
> > That's something I have never seen happening, even when I do
> > have a high load of filesystem activity, discs running at 100% for
> > extended periods while largeish trees get moved around. The system
> > certainly gets sluggish under that kind of load but nowhere near as bad
> > as that.
> 
> My experience is comparable with corecode's experience. Even moderate IO 
> load makes my audio stutter, my prompts apps hang for some seconds time 
> to time etc. It's HAMMER + AHCI. It's not a conncurrent IO issue we 

	Interesting because I'm using HAMMER + NATA, heavy IO load will
make video playback stutter but I've yet to make audio stutter.

	Corecode - are you using NATA or AHCI ?

> obviously have (due to lack of IO scheduler). Surprisingly my UFS + NATA 
> machine performs much better in this regard.

	Can you try HAMMER + NATA ?

> Not to mention http://bugs.dragonflybsd.org/issue1502 which became 
> showstopper for DragonFly + HAMMER deploying for me.

	I have no nohistory mounts but I delete 5GB files fairly often with
no ill effects on normal mounts.

-- 
Steve O'Hara-Smith                          |   Directable Mirror Arrays
C:>WIN                                      | A better way to focus the sun
The computer obeys and wins.                |    licences available see
You lose and Bill collects.                 |    http://www.sohara.org/