From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 11 Jul 2002 17:05:46 -0300 (BRT) From: Rik van Riel Subject: Re: [PATCH] Optimize out pte_chain take three In-Reply-To: <3D2DE264.17706BB4@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: William Lee Irwin III , Dave McCracken , Linux Memory Management List-ID: On Thu, 11 Jul 2002, Andrew Morton wrote: > Rik thought these are pagecache and swap thrashers, but that's not > the intent. Think of the file as program text and the malloced > memory as, well, malloced memory. > > The problem is the access pattern. It shouldn't be random-uniform. > But what should it be? random-gaussian? > Does this not capture what the VM is supposed to do? Indeed. This sounds like a much much better test. > useful pagecache and swapping everything out. Our kernels have > O_STREAMING because of this. It simply removes as much pagecache > as it can, each time ->nrpages reaches 256. It's rather effective. Now why does that remind me of drop-behind ? ;) > I installed 2.5.25+rmap on my desktop yesterday. Come in this morning > to discover half of memory is inodes, quarter of memory is dentries and > I'm 40 megs into swap. Sigh. As requested by Linus, this patch only has the mechanism and none of the balancing changes. I suspect Ed Tomlinson's patch will fix this issue. > The `working set simulator' could provide the memory hog function. > The victim application perhaps doesn't need to be anything as > fancy on day one. Maybe just a kernel compile or such? Or maybe the interactive performance measurement thing by Bob Matthews ? http://people.redhat.com/bmatthews/irman/ (IIRC) > I'll do the working set simulator. That'll give you guys something > to crunch on. Is gaussian reasonable? Sounds ok to me. kind 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/