Re: 2.6.0-test6 scheduling(?) oddness

From: Nick Piggin
Date: Tue Sep 30 2003 - 23:11:53 EST




Murray J. Root wrote:

P4 2G
1G PC2700 RAM
ASUS P4S533

Large tasks (like raytrace rendering) take double the amount of time they used
to take, although the system is nicer to the user while they run. In 2.6.0-test5 had a little trouble with it and Piggin pointed me to a patch that
fixed it and is now in -test6, however the patch didn't slow the rendering as
much as it does in test6. (Con Koliva's patch, I believe it was).
For example - rendering an image that took 15 minutes in 2.5.65 takes 20 minutes in 2.6.0-test5 (with patch) and 30 minutes in 2.6.0-test6 (raw from
kernel.org). Same config options (everything I use builtin - no modules).

A new issue (which also doesn't happen in -test5 with the patch):
When running cpu intense tasks, new (large) tasks will not start till the first
one finishes.
For example, using POV-Ray 3.5 to render an image that takes 30 minutes when it
is the only program running, start oowriter.
The render finishes in the same 30 minutes, then oowriter starts.
oowriter takes about 3 seconds to load if no rendering is going on.
I can use apps that are already open but can't start new ones while rendering.
In 2.6.0-test5 (with patch) opening oowriter while rendering takes about 1 minute.
In 2.5.65 opening oowriter while rendering takes about 2 minutes (and X gets
very hard to use till oowriter is completely done opening).


Hi Murray!
Con Kolivas' patch has been included in test6. You might have tried that
or maybe my patch?

Anyway, lets just clarify your report:
1 CPU, hyperthreading on or off?

test5 interactivity under load isn't as good as test6.

povray takes 150% more time in test6 vs tset5. How many compute threads
does povray use? Is anything else running?

oowriter takes 3 seconds to load when nothing is running
oowriter takes 30(or more) minutes to load when povray is runnnig, takes
1 minute in test5 plus patch (could you tell us exactly what the patch
is)


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