Messages in this thread | | | Date | Mon, 7 Jan 2002 08:43:04 -0800 (PST) | From | Linus Torvalds <> | Subject | Re: 2.5.2-pre performance degradation on an old 486 |
| |
On Mon, 7 Jan 2002, Matthias Hanisch wrote: > > To answer your question, I wanted to profile 2.5.2-pre8 against > 2.5.2-pre8-old-scheduler. _Fortunately_ I made some mistake and forgot to > back out the following chunk of memory. > > --- v2.5.1/linux/arch/i386/kernel/process.c Thu Oct 4 18:42:54 2001 > +++ linux/arch/i386/kernel/process.c Thu Dec 27 08:21:28 2001 > @@ -125,7 +125,6 @@ > /* endless idle loop with no priority at all */ > init_idle(); > current->nice = 20; > - current->counter = -100; > > while (1) { > void (*idle)(void) = pm_idle;
Hey, that would do it. It looks like the idle task ends up being a _normal_ process (just nice'd down), so it will get real CPU time instead of only getting scheduled when nothing else is runnable.
Davide, I think the bounce-buffer is a red herring, it's simply that we're wasting time in idle..
Linus
- 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/
| |