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 9BF2CC77B7E for ; Thu, 1 Jun 2023 08:46:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232250AbjFAIq6 (ORCPT ); Thu, 1 Jun 2023 04:46:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232208AbjFAIqV (ORCPT ); Thu, 1 Jun 2023 04:46:21 -0400 Received: from out-59.mta1.migadu.com (out-59.mta1.migadu.com [IPv6:2001:41d0:203:375::3b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0925A134 for ; Thu, 1 Jun 2023 01:46:11 -0700 (PDT) Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1685609168; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=viwhASMvyk0Cjm0jq9ZeM+ouB4uWAEMzGdt0PzGjYnA=; b=b4INK5nOSvj+75WjbDesPWXE9AWkPJLkn0CqnTqvUvZPjLpeC/weObuZD0D9N+pq2TyM+Q SLt6WHzcqRMkacOE6fFeTGK0DV1zDWyMJCvSGdyA9fkcu7loNxzGDd4xlLT3zo7YLqAg8O CHFEm/Rhuq4aIM7H7jTCHMz2EGYRaiY= Date: Thu, 1 Jun 2023 16:46:00 +0800 MIME-Version: 1.0 Subject: Re: [PATCH 0/8] make unregistration of super_block shrinker more faster Content-Language: en-US To: Andrew Morton Cc: tkhai@ya.ru, roman.gushchin@linux.dev, vbabka@suse.cz, viro@zeniv.linux.org.uk, brauner@kernel.org, djwong@kernel.org, hughd@google.com, paulmck@kernel.org, muchun.song@linux.dev, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, Qi Zheng References: <20230531095742.2480623-1-qi.zheng@linux.dev> <20230531114054.bf077db642aa9c58c0831687@linux-foundation.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <20230531114054.bf077db642aa9c58c0831687@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2023/6/1 02:40, Andrew Morton wrote: > On Wed, 31 May 2023 09:57:34 +0000 Qi Zheng wrote: > >> From: Qi Zheng >> >> Hi all, >> >> This patch series aims to make unregistration of super_block shrinker more >> faster. >> >> 1. Background >> ============= >> >> The kernel test robot noticed a -88.8% regression of stress-ng.ramfs.ops_per_sec >> on commit f95bdb700bc6 ("mm: vmscan: make global slab shrink lockless"). More >> details can be seen from the link[1] below. >> >> [1]. https://lore.kernel.org/lkml/202305230837.db2c233f-yujie.liu@intel.com/ >> >> We can just use the following command to reproduce the result: >> >> stress-ng --timeout 60 --times --verify --metrics-brief --ramfs 9 & >> >> 1) before commit f95bdb700bc6b: >> >> stress-ng: info: [11023] dispatching hogs: 9 ramfs >> stress-ng: info: [11023] stressor bogo ops real time usr time sys time bogo ops/s bogo ops/s >> stress-ng: info: [11023] (secs) (secs) (secs) (real time) (usr+sys time) >> stress-ng: info: [11023] ramfs 774966 60.00 10.18 169.45 12915.89 4314.26 >> stress-ng: info: [11023] for a 60.00s run time: >> stress-ng: info: [11023] 1920.11s available CPU time >> stress-ng: info: [11023] 10.18s user time ( 0.53%) >> stress-ng: info: [11023] 169.44s system time ( 8.82%) >> stress-ng: info: [11023] 179.62s total time ( 9.35%) >> stress-ng: info: [11023] load average: 8.99 2.69 0.93 >> stress-ng: info: [11023] successful run completed in 60.00s (1 min, 0.00 secs) >> >> 2) after commit f95bdb700bc6b: >> >> stress-ng: info: [37676] dispatching hogs: 9 ramfs >> stress-ng: info: [37676] stressor bogo ops real time usrtime sys time bogo ops/s bogo ops/s >> stress-ng: info: [37676] (secs) (secs) (secs) (real time) (usr+sys time) >> stress-ng: info: [37676] ramfs 168673 60.00 1.61 39.66 2811.08 4087.47 >> stress-ng: info: [37676] for a 60.10s run time: >> stress-ng: info: [37676] 1923.36s available CPU time >> stress-ng: info: [37676] 1.60s user time ( 0.08%) >> stress-ng: info: [37676] 39.66s system time ( 2.06%) >> stress-ng: info: [37676] 41.26s total time ( 2.15%) >> stress-ng: info: [37676] load average: 7.69 3.63 2.36 >> stress-ng: info: [37676] successful run completed in 60.10s (1 min, 0.10 secs) > > Is this comparison reversed? It appears to demonstrate that > f95bdb700bc6b made the operation faster. Maybe not. IIUC, the bogo ops/s (real time) bigger the better. Thanks, Qi >