From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 2 Sep 2002 17:50:11 -0300 (BRT) From: Rik van Riel Subject: Re: About the free page pool In-Reply-To: <3D73CB28.D2F7C7B0@zip.com.au> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Scott Kaplan , linux-mm@kvack.org List-ID: On Mon, 2 Sep 2002, Andrew Morton wrote: > > How important is it to maintain a list of free pages? That is, how > > critical is it that there be some pool of free pages from which the only > > bookkeeping required is the removal of that page from the free list. > > There are several reasons, all messy. [snip] > It's feasible. It'd take some work. Probably it would best be implemented > via a third list. That list would be protected by an IRQ-safe lock, I don't think we need to bother with the IRQ-safe part. It's much simpler if we just do: 1) have a normal free list, but have it smaller ... say, between zone->pages_min and zone->pages_low 2) if the free pages drop below the low water mark, have either a normal allocator or a kernel thread refill it to the high water mark, from the clean pages list 3) have the free+clean target set to something higher, say zone->pages_high ... we could even tune this automatically, if we run out of free+clean pages too often kswapd should probably try to keep more pages clean What do you think, would this work? regards, Rik -- Bravely reimplemented by the knights who say "NIH". http://www.surriel.com/ http://distro.conectiva.com/ -- 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-mm.org/