From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx184.postini.com [74.125.245.184]) by kanga.kvack.org (Postfix) with SMTP id 3EE956B0032 for ; Fri, 16 Aug 2013 12:36:46 -0400 (EDT) Message-ID: <520E5517.9070606@intel.com> Date: Fri, 16 Aug 2013 09:36:39 -0700 From: Dave Hansen MIME-Version: 1.0 Subject: Re: [RFC v3 0/5] Transparent on-demand struct page initialization embedded in the buddy allocator References: <1375465467-40488-1-git-send-email-nzimmer@sgi.com> <1376344480-156708-1-git-send-email-nzimmer@sgi.com> In-Reply-To: <1376344480-156708-1-git-send-email-nzimmer@sgi.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Nathan Zimmer Cc: hpa@zytor.com, mingo@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, holt@sgi.com, rob@landley.net, travis@sgi.com, daniel@numascale-asia.com, akpm@linux-foundation.org, gregkh@linuxfoundation.org, yinghai@kernel.org, mgorman@suse.de Hey Nathan, Could you post your boot timing patches? My machines are much smaller than yours, but I'm curious how things behave here as well. I did some very imprecise timings (strace -t on a telnet attached to the serial console). The 'struct page' initializations take about a minute of boot time for me to do 1TB across 8 NUMA nodes (this is a glueless QPI system[1]). My _quick_ calculations look like it's 2x as fast to initialize node0's memory vs. the other nodes, and boot time is increased by a second for about every 30G of memory we add. So even with nothing else fancy, we could get some serious improvements from just doing the initialization locally. [1] We call anything using pure QPI without any other circuitry for the NUMA interconnects to be "glueless" -- 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