Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 20 Mar 2001 13:45:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 20 Mar 2001 13:44:53 -0500 Received: from neon-gw.transmeta.com ([209.10.217.66]:48398 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Tue, 20 Mar 2001 13:44:39 -0500 Date: Tue, 20 Mar 2001 10:43:33 -0800 (PST) From: Linus Torvalds To: Serge Orlov cc: , Subject: Re: Linux 2.4.2 fails to merge mmap areas, 700% slowdown. In-Reply-To: <3AB7A169.53F4E4BB@con.mcst.ru> Message-ID: 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 On Tue, 20 Mar 2001, Serge Orlov wrote: > > I upgraded one of our computer happily running 2.2.13 kernel > to 2.4.2. Everything was OK, but compilation time of our C++ > project greatly increased (1.4 times slower). I investigated the > issue and found that g++ spends 7 times more time in kernel. > The reason for this is big vm map: Cool. Somebody actually found a real case. I'll fix the mmap case asap. Its' not hard, I just waited to see if it ever actually triggers. Something like g++ certainly counts as major. Are you willing to test out patches? Linus - 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/