From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 25 Sep 2000 01:41:37 +0200 From: Andrea Arcangeli Subject: Re: [patch] vmfixes-2.4.0-test9-B2 - fixing deadlocks Message-ID: <20000925014137.B6249@athlon.random> References: <20000924231240.D5571@athlon.random> <20000924224303.C2615@redhat.com> <20000925001342.I5571@athlon.random> <20000925003650.A20748@home.ds9a.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20000925003650.A20748@home.ds9a.nl>; from ahu@ds9a.nl on Mon, Sep 25, 2000 at 12:36:50AM +0200 Sender: owner-linux-mm@kvack.org Return-Path: To: "Stephen C. Tweedie" , Ingo Molnar , Linus Torvalds , Rik van Riel , Roger Larsson , MM mailing list , linux-kernel@vger.kernel.org List-ID: On Mon, Sep 25, 2000 at 12:36:50AM +0200, bert hubert wrote: > True. But they also appear to be found and solved at an impressive rate. We're talking about shrink_[id]cache_memory change. That have _nothing_ to do with the VM changes that happened anywhere between test8 and test9-pre6. You were talking about a different thing. > It's tempting to revert the merge, but let's work at it a bit longer. There Since you're talking about this I'll soon (as soon as I'll finish some other thing that is just work in progress) release a classzone against latest's 2.4.x. My approch is _quite_ different from the curren VM. Current approch is very imperfect and it's based solely on aging whereas classzone had hooks into pagefaults paths and all other map/unmap points to have perfect accounting of the amount of active/inactive stuff. The mapped pages was never seen by anything except swap_out, if they was mapped (it's not a if page->age then move into the active list, with classzone the page was _just_ in the active list in first place since it was mapped). I consider the current approch the wrong way to go and for this reason I prefer to spend time porting/improving classzone. In classzone the aging exists too but it's _completly_ orthogonal to how rest of the VM works. classzone had only 1 bit of aging per page to save mem_map_t array so I'll extend the aging info from 1 bit to 32bit to make it more biased. This is my humble opinion at least. I may be wrong. I'll let you know once I'll have a patch I'll happy with and some real life number to proof my theory. In the meantime if you want to go back to 2.4.0-test1-ac22-class++ to give it a try under swap to see the difference in the behaviour and compare (Mike said it's still an order of magnitude faster with his "make -j30 bzImage" testcase and he's always very reliable in his reports). Andrea -- 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/