From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41472C32793 for ; Wed, 24 Aug 2022 10:40:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236577AbiHXKkQ (ORCPT ); Wed, 24 Aug 2022 06:40:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236890AbiHXKkN (ORCPT ); Wed, 24 Aug 2022 06:40:13 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AAC180F6A for ; Wed, 24 Aug 2022 03:40:12 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 3E11020488; Wed, 24 Aug 2022 10:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1661337611; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=NfJHy3InzW1oMtUZUiCWo1JwYLeSydo4JFoewElY3I4=; b=ioQsressDeK2roKJLCSGLu0CY0cK6Twj1BftpkF2mUVvtP58jyraNS2f8/bFOcGV/wMKYt Y/+t+VwS4PnFIFnvfYk7EgpR7dui6kgavfYLqsA+mo+g3Nf0d8pjOrylUi3MZ/YESu4bEj 92IRdsKkCaUlOuKIjX3WydZwU/e2hwU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1661337611; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=NfJHy3InzW1oMtUZUiCWo1JwYLeSydo4JFoewElY3I4=; b=MBXubwSl39fHcdp8nHigfiuYgB6eExOJZ4kQ4TVjgImkQKZeRhygq2yBGVNiZvHOXBW7BP b6YGWWSz0CaR9ZCA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 2CAEA13780; Wed, 24 Aug 2022 10:40:11 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id X5/XCgsABmO1IAAAMHmgww (envelope-from ); Wed, 24 Aug 2022 10:40:11 +0000 Received: by quack3.suse.cz (Postfix, from userid 1000) id B88F6A0679; Wed, 24 Aug 2022 12:40:10 +0200 (CEST) Date: Wed, 24 Aug 2022 12:40:10 +0200 From: Jan Kara To: Stefan Wahren Cc: Jan Kara , Ted Tso , linux-ext4@vger.kernel.org, Thorsten Leemhuis , Ojaswin Mujoo , Harshad Shirwadkar Subject: Re: [PATCH 0/2] ext4: Fix performance regression with mballoc Message-ID: <20220824104010.4qvw46zmf42te53n@quack3> References: <20220823134508.27854-1-jack@suse.cz> <8e164532-c436-241f-33be-4b41f7f67235@i2se.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8e164532-c436-241f-33be-4b41f7f67235@i2se.com> Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hi Stefan! On Wed 24-08-22 12:17:14, Stefan Wahren wrote: > Am 23.08.22 um 22:15 schrieb Jan Kara: > > Hello, > > > > So I have implemented mballoc improvements to avoid spreading allocations > > even with mb_optimize_scan=1. It fixes the performance regression I was able > > to reproduce with reaim on my test machine: > > > > mb_optimize_scan=0 mb_optimize_scan=1 patched > > Hmean disk-1 2076.12 ( 0.00%) 2099.37 ( 1.12%) 2032.52 ( -2.10%) > > Hmean disk-41 92481.20 ( 0.00%) 83787.47 * -9.40%* 90308.37 ( -2.35%) > > Hmean disk-81 155073.39 ( 0.00%) 135527.05 * -12.60%* 154285.71 ( -0.51%) > > Hmean disk-121 185109.64 ( 0.00%) 166284.93 * -10.17%* 185298.62 ( 0.10%) > > Hmean disk-161 229890.53 ( 0.00%) 207563.39 * -9.71%* 232883.32 * 1.30%* > > Hmean disk-201 223333.33 ( 0.00%) 203235.59 * -9.00%* 221446.93 ( -0.84%) > > Hmean disk-241 235735.25 ( 0.00%) 217705.51 * -7.65%* 239483.27 * 1.59%* > > Hmean disk-281 266772.15 ( 0.00%) 241132.72 * -9.61%* 263108.62 ( -1.37%) > > Hmean disk-321 265435.50 ( 0.00%) 245412.84 * -7.54%* 267277.27 ( 0.69%) > > > > Stefan, can you please test whether these patches fix the problem for you as > > well? Comments & review welcome. > > i tested the whole series against 5.19 and 6.0.0-rc2. In both cases the > update process succeed which is a improvement, but the download + unpack > duration ( ~ 7 minutes ) is not as good as with mb_optimize_scan=0 ( ~ 1 > minute ). OK, thanks for testing! I'll try to check specifically untar whether I can still see some differences in the IO pattern on my test machine. > Unfortuntately i don't have much time this week and next week i'm in > holidays. No problem. > Just a question, my tests always had MBCACHE=y . Is it possible that the > mb_optimize_scan is counterproductive for MBCACHE in this case? MBCACHE (despite similar name) is actually related to extended attributes so it likely has no impact on your workload. > I'm asking because before the download the update script removes the files > from the previous update process which already cause a high load. Do you mean already the removal step is noticeably slower with mb_optimize_scan=1? The removal will be modifying directory blocks, inode table blocks, block & inode bitmaps, and group descriptors. So if block allocations are more spread (due to mb_optimize_scan=1 used during the untar), the removal may also take somewhat longer. Honza -- Jan Kara SUSE Labs, CR