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 X-Spam-Level: X-Spam-Status: No, score=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C24EC43460 for ; Mon, 26 Apr 2021 01:31:19 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 208F961354 for ; Mon, 26 Apr 2021 01:31:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 208F961354 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 795CB900002; Sun, 25 Apr 2021 21:31:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 744676B0075; Sun, 25 Apr 2021 21:31:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5BF24900002; Sun, 25 Apr 2021 21:31:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0082.hostedemail.com [216.40.44.82]) by kanga.kvack.org (Postfix) with ESMTP id 3A4606B0074 for ; Sun, 25 Apr 2021 21:31:18 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id DF980824999B for ; Mon, 26 Apr 2021 01:31:17 +0000 (UTC) X-FDA: 78072790194.15.E93E078 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf14.hostedemail.com (Postfix) with ESMTP id 5FD4CC0007D7 for ; Mon, 26 Apr 2021 01:31:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619400677; 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: in-reply-to:in-reply-to:references:references; bh=CSS6BiOqp8JvHgJiETTDxrWSdTxLypre92kI0mHmhKM=; b=c4CpYQ/99jNyEAuzCCnMPOB1fobwdEwVSyoTbKF5IEvnKnXKpofN+M24BByHuiYSeHQVs7 ARF0zaCdQy+9mXdOOIL7tF48+gJRwW9ZYKu9GbIcr3H/JHEpUh8QygQf5OA2W5FZC0IeCh LzbI7ocL9msVmk+UPccvU8wH3dPJFBo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-316-tRYflDinMRuTunkiegw6FQ-1; Sun, 25 Apr 2021 21:31:13 -0400 X-MC-Unique: tRYflDinMRuTunkiegw6FQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4B33281746A; Mon, 26 Apr 2021 01:31:11 +0000 (UTC) Received: from t490s.aquini.net (ovpn-112-122.phx2.redhat.com [10.3.112.122]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7779319D7D; Mon, 26 Apr 2021 01:31:09 +0000 (UTC) Date: Sun, 25 Apr 2021 21:31:07 -0400 From: Rafael Aquini To: chukaiping Cc: mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com, akpm@linux-foundation.org, vbabka@suse.cz, nigupta@nvidia.com, bhe@redhat.com, khalid.aziz@oracle.com, iamjoonsoo.kim@lge.com, mateusznosek0@gmail.com, sh_def@163.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3] mm/compaction:let proactive compaction order configurable Message-ID: References: <1619313662-30356-1-git-send-email-chukaiping@baidu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1619313662-30356-1-git-send-email-chukaiping@baidu.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Stat-Signature: k9kdnyxxck7s5auygaebrjebfqa3uc4u X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 5FD4CC0007D7 Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf14; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=170.10.133.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619400663-678900 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Apr 25, 2021 at 09:21:02AM +0800, chukaiping wrote: > Currently the proactive compaction order is fixed to > COMPACTION_HPAGE_ORDER(9), it's OK in most machines with lots of > normal 4KB memory, but it's too high for the machines with small > normal memory, for example the machines with most memory configured > as 1GB hugetlbfs huge pages. In these machines the max order of > free pages is often below 9, and it's always below 9 even with hard > compaction. This will lead to proactive compaction be triggered very > frequently. In these machines we only care about order of 3 or 4. > This patch export the oder to proc and let it configurable > by user, and the default value is still COMPACTION_HPAGE_ORDER. > > Signed-off-by: chukaiping > Reported-by: kernel test robot Two minor nits on the commit log message: * there seems to be a whitespage missing in your short log: "... mm/compaction:let ..." * has the path really been reported by a test robot? A note on the sysctl name, I'd suggest that it perhaps should reflect the fact that we're adjusting the order for proactive compation. How about "proactive_compation_order"? Cheers, > --- > > Changes in v3: > - change the min value of compaction_order to 1 because the fragmentation > index of order 0 is always 0 > - move the definition of max_buddy_zone into #ifdef CONFIG_COMPACTION > > Changes in v2: > - fix the compile error in ia64 and powerpc, move the initialization > of sysctl_compaction_order to kcompactd_init because > COMPACTION_HPAGE_ORDER is a variable in these architectures > - change the hard coded max order number from 10 to MAX_ORDER - 1 > > include/linux/compaction.h | 1 + > kernel/sysctl.c | 10 ++++++++++ > mm/compaction.c | 9 ++++++--- > 3 files changed, 17 insertions(+), 3 deletions(-) > > diff --git a/include/linux/compaction.h b/include/linux/compaction.h > index ed4070e..151ccd1 100644 > --- a/include/linux/compaction.h > +++ b/include/linux/compaction.h > @@ -83,6 +83,7 @@ static inline unsigned long compact_gap(unsigned int order) > #ifdef CONFIG_COMPACTION > extern int sysctl_compact_memory; > extern unsigned int sysctl_compaction_proactiveness; > +extern unsigned int sysctl_compaction_order; > extern int sysctl_compaction_handler(struct ctl_table *table, int write, > void *buffer, size_t *length, loff_t *ppos); > extern int sysctl_extfrag_threshold; > diff --git a/kernel/sysctl.c b/kernel/sysctl.c > index 62fbd09..e50f7d2 100644 > --- a/kernel/sysctl.c > +++ b/kernel/sysctl.c > @@ -196,6 +196,7 @@ enum sysctl_writes_mode { > #endif /* CONFIG_SCHED_DEBUG */ > > #ifdef CONFIG_COMPACTION > +static int max_buddy_zone = MAX_ORDER - 1; > static int min_extfrag_threshold; > static int max_extfrag_threshold = 1000; > #endif > @@ -2871,6 +2872,15 @@ int proc_do_static_key(struct ctl_table *table, int write, > .extra2 = &one_hundred, > }, > { > + .procname = "compaction_order", > + .data = &sysctl_compaction_order, > + .maxlen = sizeof(sysctl_compaction_order), > + .mode = 0644, > + .proc_handler = proc_dointvec_minmax, > + .extra1 = SYSCTL_ONE, > + .extra2 = &max_buddy_zone, > + }, > + { > .procname = "extfrag_threshold", > .data = &sysctl_extfrag_threshold, > .maxlen = sizeof(int), > diff --git a/mm/compaction.c b/mm/compaction.c > index e04f447..70c0acd 100644 > --- a/mm/compaction.c > +++ b/mm/compaction.c > @@ -1925,16 +1925,16 @@ static bool kswapd_is_running(pg_data_t *pgdat) > > /* > * A zone's fragmentation score is the external fragmentation wrt to the > - * COMPACTION_HPAGE_ORDER. It returns a value in the range [0, 100]. > + * sysctl_compaction_order. It returns a value in the range [0, 100]. > */ > static unsigned int fragmentation_score_zone(struct zone *zone) > { > - return extfrag_for_order(zone, COMPACTION_HPAGE_ORDER); > + return extfrag_for_order(zone, sysctl_compaction_order); > } > > /* > * A weighted zone's fragmentation score is the external fragmentation > - * wrt to the COMPACTION_HPAGE_ORDER scaled by the zone's size. It > + * wrt to the sysctl_compaction_order scaled by the zone's size. It > * returns a value in the range [0, 100]. > * > * The scaling factor ensures that proactive compaction focuses on larger > @@ -2666,6 +2666,7 @@ static void compact_nodes(void) > * background. It takes values in the range [0, 100]. > */ > unsigned int __read_mostly sysctl_compaction_proactiveness = 20; > +unsigned int __read_mostly sysctl_compaction_order; > > /* > * This is the entry point for compacting all nodes via > @@ -2958,6 +2959,8 @@ static int __init kcompactd_init(void) > int nid; > int ret; > > + sysctl_compaction_order = COMPACTION_HPAGE_ORDER; > + > ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, > "mm/compaction:online", > kcompactd_cpu_online, NULL); > -- > 1.7.1 >