From patchwork Tue Jan 28 00:16:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Minchan Kim X-Patchwork-Id: 11353391 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 28C0A924 for ; Tue, 28 Jan 2020 00:17:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E0E5424656 for ; Tue, 28 Jan 2020 00:17:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gcx1AwE/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0E5424656 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C92D76B000A; Mon, 27 Jan 2020 19:17:05 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id C1B236B000C; Mon, 27 Jan 2020 19:17:05 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ABC8A6B000D; Mon, 27 Jan 2020 19:17:05 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0146.hostedemail.com [216.40.44.146]) by kanga.kvack.org (Postfix) with ESMTP id 8F23E6B000A for ; Mon, 27 Jan 2020 19:17:05 -0500 (EST) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 611D6181AEF09 for ; Tue, 28 Jan 2020 00:17:05 +0000 (UTC) X-FDA: 76425128010.11.moon06_5aeea57063c11 X-Spam-Summary: 30,2,0,38a38a48a73182af,d41d8cd98f00b204,minchan.kim@gmail.com,:akpm@linux-foundation.org:linux-kernel@vger.kernel.org::linux-api@vger.kernel.org:oleksandr@redhat.com:surenb@google.com:timmurray@google.com:dancol@google.com:sspatil@google.com:sonnyrao@google.com:bgeffon@google.com:mhocko@suse.com:hannes@cmpxchg.org:shakeelb@google.com:joaodias@google.com:joel@joelfernandes.org:minchan@kernel.org,RULES_HIT:41:355:379:541:800:960:967:973:988:989:1260:1311:1314:1345:1359:1437:1515:1535:1542:1711:1730:1747:1777:1792:2393:2525:2559:2563:2682:2685:2693:2859:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3354:3865:3866:3867:3868:3870:3871:3872:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4250:4321:4823:5007:6119:6120:6261:6653:6742:7576:7901:7903:8557:9025:10004:11026:11658:11914:12043:12296:12297:12438:12517:12519:12555:12679:12895:13869:13894:14181:14394:14721:21080:21222:21444:21451:21524:21611:21627:21740:21772:21889:21990:30005:3 0034:300 X-HE-Tag: moon06_5aeea57063c11 X-Filterd-Recvd-Size: 5723 Received: from mail-pf1-f195.google.com (mail-pf1-f195.google.com [209.85.210.195]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Tue, 28 Jan 2020 00:17:04 +0000 (UTC) Received: by mail-pf1-f195.google.com with SMTP id q8so5701698pfh.7 for ; Mon, 27 Jan 2020 16:17:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=byMHrtK1k5FQWktxNZKgpIEhIdZ+jOjWAb7BIyi4lBA=; b=gcx1AwE/bXt90sOnHE8tkitJggiidEQCzgaEc9elcFPregk1F09926WnR6sPAg3NHJ mIdBVj3BsjX81nGowuT7nAHRs/GrhviVJ0DG0ewbqf9nFz7NW9teL64pZ80eInjpolPq tt9YXVZIlEnxXxs3ICAKN+eSUjOOAUjpIiPgAi6cSZGda3zZyEN1/53WSOo3HCGu4l9/ G0DIYIfxA5E7gL/I1DcIRTTnJgrEP+6HhyO/1n2jPWRNKAeF6JjqwMi/diaeEbctuQxz 8C/6+fIHhoD0HaL7Cugo9ZHJUBLrc+HiU4S3OW9lz1c1njwkgnk1GWxa564lMnoHTJP9 oNXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=byMHrtK1k5FQWktxNZKgpIEhIdZ+jOjWAb7BIyi4lBA=; b=jYNpMYqI0R/U7bR5YQS0N75g5VnNS52KaBYnf7HNMcGMOC4hBSTEv2hGO4yulljPuw +LlSiOEqEphPKMqe28bjbIsC0/LOYu9Jn1KZ47J2EDFIwiFYHTs0iEIQo6olZWBfqg3f 2KG7toDRB980vc38xxARWcIkoAPQUZYdISmRQ/h/K5OjCjWFqkWPTv2a+ZJ6e220+6v7 /qI5zuwuQdxeNXPEeaiGj9RjUu+HaDzMdlX7OMgg8KfUw+tzfUXzNV9sE4F1CnYtBEv3 HuTMGNvmqISpyRmWIQixlpsbUSF7urW/CAOMWIsFR2IVSUWHcUoCX1TYgn/18YEsoUXq PNNw== X-Gm-Message-State: APjAAAV1AZO3z+H3svAYBTJsm5HykQUl/VeYBiYIkC0jZUjhu1vt31OP uLsopqBX+iYCI6JvdLOsHTs= X-Google-Smtp-Source: APXvYqx9+zAHx+aMRolYkWKe8SUK4zOvH2qwG7qZk5YBG1aQfIomoeisjAxibGaMfQWIJ4KB7xfjJA== X-Received: by 2002:aa7:9a96:: with SMTP id w22mr1189196pfi.210.1580170623768; Mon, 27 Jan 2020 16:17:03 -0800 (PST) Received: from bbox-1.mtv.corp.google.com ([2620:15c:211:1:3e01:2939:5992:52da]) by smtp.gmail.com with ESMTPSA id q28sm11301461pfl.153.2020.01.27.16.17.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2020 16:17:02 -0800 (PST) From: Minchan Kim To: Andrew Morton Cc: LKML , linux-mm , linux-api@vger.kernel.org, oleksandr@redhat.com, Suren Baghdasaryan , Tim Murray , Daniel Colascione , Sandeep Patil , Sonny Rao , Brian Geffon , Michal Hocko , Johannes Weiner , Shakeel Butt , John Dias , Joel Fernandes , Minchan Kim Subject: [PATCH v3 4/5] mm/madvise: allow KSM hints for remote API Date: Mon, 27 Jan 2020 16:16:40 -0800 Message-Id: <20200128001641.5086-5-minchan@kernel.org> X-Mailer: git-send-email 2.25.0.341.g760bfbb309-goog In-Reply-To: <20200128001641.5086-1-minchan@kernel.org> References: <20200128001641.5086-1-minchan@kernel.org> MIME-Version: 1.0 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: From: Oleksandr Natalenko It all began with the fact that KSM works only on memory that is marked by madvise(). And the only way to get around that is to either: * use LD_PRELOAD; or * patch the kernel with something like UKSM or PKSM. (i skip ptrace can of worms here intentionally) To overcome this restriction, lets employ a new remote madvise API. This can be used by some small userspace helper daemon that will do auto-KSM job for us. I think of two major consumers of remote KSM hints: * hosts, that run containers, especially similar ones and especially in a trusted environment, sharing the same runtime like Node.js; * heavy applications, that can be run in multiple instances, not limited to opensource ones like Firefox, but also those that cannot be modified since they are binary-only and, maybe, statically linked. Speaking of statistics, more numbers can be found in the very first submission, that is related to this one [1]. For my current setup with two Firefox instances I get 100 to 200 MiB saved for the second instance depending on the amount of tabs. 1 FF instance with 15 tabs: $ echo "$(cat /sys/kernel/mm/ksm/pages_sharing) * 4 / 1024" | bc 410 2 FF instances, second one has 12 tabs (all the tabs are different): $ echo "$(cat /sys/kernel/mm/ksm/pages_sharing) * 4 / 1024" | bc 592 At the very moment I do not have specific numbers for containerised workload, but those should be comparable in case the containers share similar/same runtime. [1] https://lore.kernel.org/patchwork/patch/1012142/ Signed-off-by: Oleksandr Natalenko Signed-off-by: Minchan Kim --- mm/madvise.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/madvise.c b/mm/madvise.c index bc0a72dbf80e..39c40cbb389e 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1002,6 +1002,10 @@ process_madvise_behavior_valid(int behavior) switch (behavior) { case MADV_COLD: case MADV_PAGEOUT: +#ifdef CONFIG_KSM + case MADV_MERGEABLE: + case MADV_UNMERGEABLE: +#endif return true; default: return false;