Re: [PATCH] Re: kswapd
From: Linus Torvalds <torvalds@transmeta.com>
Date: 2000-03-27 06:07:48
On Sun, 26 Mar 2000, Kanoj Sarcar wrote:
What is the problem that your patch is fixing?
I agree with Rik's patch - the old behaviour kicked us out of the regular loop whenever "need_resched" was set, and that is not necessarily a good idea at all.
From a conceptual standpoint, going to sleep when "need_resched" gets set
is not the right thing at all - the flag doesn't really have any bearing on whether kswapd should sleep, it only has meaning from a scheduling latency standpoint (ie "need_resched" does not mean "go to sleep", it means "let somebody else run now" - different things). On the other hand you're definitely right that this is not a new bug introduced by you, Kanoj - this seems to be just a thinko that has been there for a long long time. And I suspect I may have been the original perpetrator of the crime. The new code looks much saner: it reschedules when asked to, and it stops looping when it makes sense (ie when there is no longer any reason to free pages). Instead of mixing the two up. Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/