Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 17 Jul 2002 08:19:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 17 Jul 2002 08:19:08 -0400 Received: from garrincha.netbank.com.br ([200.203.199.88]:26629 "HELO garrincha.netbank.com.br") by vger.kernel.org with SMTP id ; Wed, 17 Jul 2002 08:19:06 -0400 Date: Wed, 17 Jul 2002 09:21:50 -0300 (BRT) From: Rik van Riel X-X-Sender: riel@imladris.surriel.com To: Andrew Morton cc: Linus Torvalds , lkml Subject: Re: [patch 1/13] minimal rmap In-Reply-To: <3D3500AA.131CE2EB@zip.com.au> Message-ID: X-spambait: aardvark@kernelnewbies.org X-spammeplease: aardvark@nl.linux.org MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1967 Lines: 59 On Tue, 16 Jul 2002, Andrew Morton wrote: > The rest of the VM - list management, the classzone concept, etc > remains unchanged. > 5: per-cpu pte_chain freelists (Rik?) Will look into this soon. > 6: maybe GC the pte_chain backing pages. (Seems unavoidable. Rik?) And probably into this, if it turns out that we're wasting too much memory in no longer used pte_chains in real workloads, which will probably happen ;) > 7: multithread the page reclaim code. (I have patches). Rmap for 2.4 also has some code which could be used for this. > 8: clustered add-to-swap. Not sure if I buy this. anon pages are > often well-ordered-by-virtual-address on the LRU, so it "just > works" for benchmarky loads. But there may be some other loads... Benchmarky loads without a working set probably aren't all that suitable for evaluating page replacement. VM (and general caching) works _because_ of the working set property. Does anybody know of a working set simulator we could use to test things like this ? > 9: Fix bad IO latency in page reclaim (I have lame patches) > > 10: Develop tuning tools, use them. > > 11: The nightly updatedb run is still evicting everything. That's the "minimal" part of "minimal rmap" ;)) Ed Tomlinson has some code for 11), which should be mergeable soon. In combination with changed page replacement priorities we'll be able to make sure updatedb won't evict everything. The importance of rmap here is making sure we're _able_ to do this kind of tuning instead of tweaking the same magic knobs we've (unsuccessfully) tweaked in the last 8 years. regards, Rik -- Bravely reimplemented by the knights who say "NIH". http://www.surriel.com/ http://distro.conectiva.com/ - 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/