From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id 697846B0069 for ; Fri, 13 Jan 2017 04:19:04 -0500 (EST) Received: by mail-pf0-f200.google.com with SMTP id c73so113142184pfb.7 for ; Fri, 13 Jan 2017 01:19:04 -0800 (PST) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id d11si12024879plj.282.2017.01.13.01.19.03 for ; Fri, 13 Jan 2017 01:19:03 -0800 (PST) Date: Fri, 13 Jan 2017 09:19:04 +0000 From: Will Deacon Subject: Re: [PATCH v3] arm64: mm: Fix NOMAP page initialization Message-ID: <20170113091903.GA22538@arm.com> References: <20161216165437.21612-1-rrichter@cavium.com> <20170109115320.GI4930@rric.localdomain> <20170112160535.GF13843@arm.com> <20170112185825.GE5020@rric.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170112185825.GE5020@rric.localdomain> Sender: owner-linux-mm@kvack.org List-ID: To: Robert Richter Cc: Ard Biesheuvel , Hanjun Guo , Russell King , Catalin Marinas , David Daney , Mark Rutland , James Morse , Yisheng Xie , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" On Thu, Jan 12, 2017 at 07:58:25PM +0100, Robert Richter wrote: > On 12.01.17 16:05:36, Will Deacon wrote: > > On Mon, Jan 09, 2017 at 12:53:20PM +0100, Robert Richter wrote: > > > > Kernel compile times (3 runs each): > > > > > > pfn_valid_within(): > > > > > > real 6m4.088s > > > user 372m57.607s > > > sys 16m55.158s > > > > > > real 6m1.532s > > > user 372m48.453s > > > sys 16m50.370s > > > > > > real 6m4.061s > > > user 373m18.753s > > > sys 16m57.027s > > > > Did you reboot the machine between each build here, or only when changing > > kernel? If the latter, do you see variations in kernel build time by simply > > rebooting the same Image? > > I built it in a loop on the shell, so no reboots between builds. Note > that I was building the kernel in /dev/shm to not access harddisks. I > think build times should be comparable then since there is no fs > caching. I guess I'm really asking what the standard deviation is if you *do* reboot between builds, using the same kernel. It's hard to tell whether the numbers are due to the patches, or just because of noise incurred by the way things happen to initialise. Will -- 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-mm.org/ . Don't email: email@kvack.org