From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id 16C4B8E0001 for ; Thu, 20 Dec 2018 22:33:27 -0500 (EST) Received: by mail-ed1-f70.google.com with SMTP id 39so4596631edq.13 for ; Thu, 20 Dec 2018 19:33:27 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id n10sor13431072edq.15.2018.12.20.19.33.25 for (Google Transport Security); Thu, 20 Dec 2018 19:33:26 -0800 (PST) Date: Fri, 21 Dec 2018 03:33:24 +0000 From: Wei Yang Subject: Re: [PATCH v2] mm/slub: improve performance by skipping checked node in get_any_partial() Message-ID: <20181221033324.ct5haaf7pygzgix4@master> Reply-To: Wei Yang References: <20181108011204.9491-1-richard.weiyang@gmail.com> <20181120033119.30013-1-richard.weiyang@gmail.com> <20181220144107.9376344c2be687615ea9aa69@linux-foundation.org> <01000167ce692d0d-ef68fdc8-4c30-40a4-8ca5-afbc3773c075-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <01000167ce692d0d-ef68fdc8-4c30-40a4-8ca5-afbc3773c075-000000@email.amazonses.com> Sender: owner-linux-mm@kvack.org List-ID: To: Christopher Lameter Cc: Andrew Morton , Wei Yang , penberg@kernel.org, mhocko@kernel.org, linux-mm@kvack.org, Joonsoo Kim , David Rientjes On Fri, Dec 21, 2018 at 01:37:38AM +0000, Christopher Lameter wrote: >On Thu, 20 Dec 2018, Andrew Morton wrote: > >> The result of (get_partial_count / get_partial_try_count): >> >> +----------+----------------+------------+-------------+ >> | | Base | Patched | Improvement| >> +----------+----------------+------------+-------------+ >> |One Node | 1:3 | 1:0 | - 100% | > >If you have one node then you already searched all your slabs. So we could >completely skip the get_any_partial() functionality in the non NUMA case >(if nr_node_ids == 1) > Yes, agree. > >> +----------+----------------+------------+-------------+ >> |Four Nodes| 1:5.8 | 1:2.5 | - 56% | >> +----------+----------------+------------+-------------+ > >Hmm.... Ok but that is the extreme slowpath. > >> Each version/system configuration combination has four round kernel >> build tests. Take the average result of real to compare. >> >> +----------+----------------+------------+-------------+ >> | | Base | Patched | Improvement| >> +----------+----------------+------------+-------------+ >> |One Node | 4m41s | 4m32s | - 4.47% | >> +----------+----------------+------------+-------------+ >> |Four Nodes| 4m45s | 4m39s | - 2.92% | >> +----------+----------------+------------+-------------+ > >3% on the four node case? That means that the slowpath is taken >frequently. Wonder why? Hmm... not sure. > >Can we also see the variability? Since this is a NUMA system there is >bound to be some indeterminism in those numbers. Oops, I have deleted those raw data. I need to retest this. -- Wei Yang Help you, Help me