From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: Subtle MM bug References: Reply-To: zlatko@iskon.hr From: Zlatko Calusic Date: 09 Jan 2001 03:01:52 +0100 In-Reply-To: Rik van Riel's message of "Sun, 7 Jan 2001 19:37:06 -0200 (BRDT)" Message-ID: <87y9wlh4a7.fsf@atlas.iskon.hr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Rik van Riel writes: > Now if 2.4 has worse _performance_ than 2.2 due to one > reason or another, that I'd like to hear about ;) > Oh, well, it seems that I was wrong. :) First test: hogmem 180 5 = allocate 180MB and dirty it 5 times (on a 192MB machine) kernel | swap usage | speed ------------------------------- 2.2.17 | 48 MB | 11.8 MB/s ------------------------------- 2.4.0 | 206 MB | 11.1 MB/s ------------------------------- So 2.2 is only marginally faster. Also it can be seen that 2.4 uses 4 times more swap space. If Linus says it's ok... :) Second test: kernel compile make -j32 (empirically this puts the VM under load, but not excessively!) 2.2.17 -> make -j32 392.49s user 47.87s system 168% cpu 4:21.13 total 2.4.0 -> make -j32 389.59s user 31.29s system 182% cpu 3:50.24 total Now, is this great news or what, 2.4.0 is definitely faster. -- Zlatko -- 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/