From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.133]:46060 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726792AbfAIRoG (ORCPT ); Wed, 9 Jan 2019 12:44:06 -0500 Date: Wed, 9 Jan 2019 09:44:03 -0800 From: Matthew Wilcox To: Waiman Long Cc: Andrew Morton , Alexey Dobriyan , Kees Cook , Thomas Gleixner , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Davidlohr Bueso , Miklos Szeredi , Daniel Colascione , Dave Chinner , Randy Dunlap Subject: Re: [PATCH v2 0/4] /proc/stat: Reduce irqs counting performance overhead Message-ID: <20190109174403.GN6310@bombadil.infradead.org> References: <1547054628-12703-1-git-send-email-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1547054628-12703-1-git-send-email-longman@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed, Jan 09, 2019 at 12:23:44PM -0500, Waiman Long wrote: > This v2 patch optimizes the way the IRQ counts are retrieved and computed > and getting rid of the sysctl parameter altogether to achieve a performance > gain that is close to the v1 patch. This is based on the idea that while > many IRQs can be supported by a system, only a handful of them are actually > being used in most cases. We can save a lot of time by focusing on those > active IRQs only and ignore the rests. So your reaction to being told "Make this the same as every other thing we have to sum across all CPUs" is to make it _even more different_ and special-cased? I'm done. NAK.