From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964947AbWGFHaF (ORCPT ); Thu, 6 Jul 2006 03:30:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964949AbWGFHaF (ORCPT ); Thu, 6 Jul 2006 03:30:05 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:2960 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S964947AbWGFHaD (ORCPT ); Thu, 6 Jul 2006 03:30:03 -0400 Date: Thu, 6 Jul 2006 09:25:29 +0200 From: Ingo Molnar To: "Eric W. Biederman" Cc: Andrew Morton , kmannth@gmail.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, Natalie.Protasevich@UNISYS.com Subject: Re: 2.6.17-mm6 Message-ID: <20060706072529.GA12317@elte.hu> References: <20060705155037.7228aa48.akpm@osdl.org> <20060705164457.60e6dbc2.akpm@osdl.org> <20060705164820.379a69ba.akpm@osdl.org> <20060705172545.815872b6.akpm@osdl.org> <20060705225905.53e61ca0.akpm@osdl.org> <20060705233123.dcb0a10b.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -3.1 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-3.1 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] 0.2 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Eric W. Biederman wrote: > What is scary is that at 1K cpus if we wind up using all of the irqs > we start consuming 1Gig of RAM. At only 128 cpus we are still in the > 2M-15M territory, so that isn't too scary. The point is that after a > certain put the memory usage for all of those counters goes insane. we just need to move kernel_stat.irqs out of the per-cpu area and alloc_percpu() a counter pointer for each IRQ that is truly set up. If someone ends up using more than say 10,000 irqs we can reconsider. With 10K irqs we'd have 10MB of stat counter footprint - that's reasonable. Ingo