From nobody Fri Jul 02 23:56:40 2021 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id CFD6111E4CB6 for ; Fri, 2 Jul 2021 23:56:43 +0000 (UTC) (envelope-from gusev.vitaliy@gmail.com) Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GGsSC1RJ8z4d3C; Fri, 2 Jul 2021 23:56:43 +0000 (UTC) (envelope-from gusev.vitaliy@gmail.com) Received: by mail-lf1-x133.google.com with SMTP id a15so21001945lfr.6; Fri, 02 Jul 2021 16:56:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:mime-version:subject:message-id:date:cc:to; bh=ehlbtiMz3vNMb25E04gIao2phmRWnfWDuFphmj8o6O4=; b=TWzBPwjQ2n7cggFzXgXdBJ93ce2R+fwS4nhQKBHV3pNAVeQdF1Bbe1Ef4M1ulfNqvm onbLzsUsTXLRe5Pkme1qXFoPme5/7zhwuQqoO91Oei7jYWlDK8x4kcN4hLkdNqoXtdYG DqFFo+xfTI2IicGZCbY8dixJywJESAvaDNbgZvgiP8DQZEm803HPLZ6cl9FYqhrvsk4s 9cMzViNNlTSHErHvZJUhfWKjAltwH14OulCOsdeEnsGjXv5Xe498r7i7ZoOfuYxeqxyF MF9mLwmMPDKndvdyl/BzjC+Kt8Yy7wV2znKafokCJx1pQfBh0o1wxjKBIsymkd00At/S 8EPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:mime-version:subject:message-id:date:cc:to; bh=ehlbtiMz3vNMb25E04gIao2phmRWnfWDuFphmj8o6O4=; b=pT2BvVd4g5y/tEb7cSIYLKAQDLr87MayRQWSJCMrLGuzyU01kVtxEF8fdQo8x4t4BU 82UzVO2aTiPwRJPlO+dL2jcd7WE1Plw1hoNdg3HZ07393OfzJxDKH2c65x4n5m3XmREx eCxuP6wtdTRnhpe/9pJrgWGgiov56MdzA3C6flRMzh7kDmSOHDsThIkmixZRjYk8DOJD jS3dMiJPavD7DsSb8miKBP40QMa9Ae+Tn/yg2etAuX8EsxkPcispmk0YHhwjYcHT05NR n4KXBU4W+xTe0lJ1rLA+aYOnoTuRLnEzxbmzANaFcE13eE4nKr5AiIfNGrFMpptcaS52 VFoA== X-Gm-Message-State: AOAM533UK+pRjj+5RjsJIJw/wW7efwE5CLS1iN1GkOO1f5QlOhBLKV19 GSqR/KW+gnUzsVeWFRuRbLLDhQ34/fs= X-Google-Smtp-Source: ABdhPJyQQHgceD1UfkqWqMy5QTUAw1kJJwmW+OW+tj6cYMOscj4qCJotfwSR2stZHX63xz4YHZQtJg== X-Received: by 2002:a05:6512:3186:: with SMTP id i6mr1529497lfe.291.1625270201610; Fri, 02 Jul 2021 16:56:41 -0700 (PDT) Received: from [10.42.0.5] ([188.187.60.230]) by smtp.gmail.com with ESMTPSA id l15sm400552lfh.228.2021.07.02.16.56.40 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 02 Jul 2021 16:56:40 -0700 (PDT) From: Vitaliy Gusev Content-Type: multipart/alternative; boundary="Apple-Mail=_561E82D1-B4FD-48AE-BAD7-E731D542BAD9" List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.7\)) Subject: madvise(MADV_FREE) doesn't work in some cases? Message-Id: Date: Sat, 3 Jul 2021 02:56:40 +0300 Cc: Konstantin Belousov To: freebsd-hackers@freebsd.org X-Mailer: Apple Mail (2.3608.120.23.2.7) X-Rspamd-Queue-Id: 4GGsSC1RJ8z4d3C X-Spamd-Bar: ++ Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20161025 header.b=TWzBPwjQ; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of gusevvitaliy@gmail.com designates 2a00:1450:4864:20::133 as permitted sender) smtp.mailfrom=gusevvitaliy@gmail.com X-Spamd-Result: default: False [2.21 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2a00:1450:4000::/36:c]; FREEMAIL_FROM(0.00)[gmail.com]; HAS_ATTACHMENT(0.00)[]; MV_CASE(0.50)[]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[gmail.com:+]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; FROM_EQ_ENVFROM(0.00)[]; SUBJECT_ENDS_QUESTION(1.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:+,3:~,4:~,5:~]; FREEMAIL_ENVFROM(0.00)[gmail.com]; MID_RHS_MATCH_FROM(0.00)[]; TAGGED_FROM(0.00)[]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; ARC_NA(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a00:1450:4864:20::133:from]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20161025]; RECEIVED_SPAMHAUS_PBL(0.00)[188.187.60.230:received]; FROM_HAS_DN(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com:dkim]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[multipart/alternative,text/plain,multipart/mixed]; MIME_BAD_ATTACHMENT(1.60)[c]; NEURAL_SPAM_MEDIUM(0.11)[0.110]; NEURAL_SPAM_SHORT(1.00)[1.000]; SPAMHAUS_ZRD(0.00)[2a00:1450:4864:20::133:from:127.0.2.255]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::133:from]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-hackers] X-Spam: Yes X-ThisMailContainsUnwantedMimeParts: Y --Apple-Mail=_561E82D1-B4FD-48AE-BAD7-E731D542BAD9 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Hi,=20 I came across not expected behaviour with madvise() in FreeBSD. Attached test program mmapfork does: mmap, fork, touch memory and then = madvise(MADV_FREE). Expected behaviour - one process can allocate memory (lazy allocation) = while system is freeing previously allocated memory for a second = process. Current behaviour - system kills one process with message in dmesg: pid 31314 (mmapfork), jid 0, uid 1001, was killed: out of swap space Running this test in Linux or illumos shows expected behaviour with a = little difference in illumos - it frees memory almost immediately, w/o = needs lack of memory in a system. If use MADV_NOTNEED - no changes. If modify program and do not do fork(), but run two instances - that = shows expected behaviour. To reproduce just disable swap, and run program with argument as 1/2 RAM = on a system. For instance, command below will try run and use ~ 2GB area = twice. [vetal@bsdev ~]$ ./mmapfork 2000 Testing program is attached. Note, during testing I disabled swap on all systems: Linux, illumos and = FreeBSD. Does it mean madvise() doesn't work well in FreeBSD or test does = something wrong? Thanks, Vitaliy Gusev --Apple-Mail=_561E82D1-B4FD-48AE-BAD7-E731D542BAD9 Content-Type: multipart/mixed; boundary="Apple-Mail=_1525D0A7-8A3B-4A8C-9910-463C30219109" --Apple-Mail=_1525D0A7-8A3B-4A8C-9910-463C30219109-- --Apple-Mail=_561E82D1-B4FD-48AE-BAD7-E731D542BAD9--