From nobody Mon Jul 12 11:55:37 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 686A6127B8CF for ; Mon, 12 Jul 2021 11:55:41 +0000 (UTC) (envelope-from gusev.vitaliy@gmail.com) Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) (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 4GNhzc4M9Mz3F40; Mon, 12 Jul 2021 11:55:40 +0000 (UTC) (envelope-from gusev.vitaliy@gmail.com) Received: by mail-lf1-x12d.google.com with SMTP id q16so6514684lfa.5; Mon, 12 Jul 2021 04:55:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=z4pqoHE0ZSZsOuRJ7PSebmJfdfkZoT4YvWuUtvc7XKw=; b=ZyQ48whOELwyfKeV8JpLG9cOuEGiW6ybIrc2W3Q2PP24IqSBeLk7Se+A0YnjQTiSiQ aZohKncdOuJWrSsMPKWPO4hrJVJiK+/zdH3G52Qi3JpqwgnNeAvw6m/dJjwViLJ7eOKb MWkQeDKI/XInPDlE2lVpZN+9ptY54TtQjtbX9E9hsqT3XjiWD7iv4huy2yCJufqzCD9u +XBvnnLaS+6jTgetKUH1k+oy8E7jUiNi1v4KwcGGSER/Bo0MB1g+NU0HKyFvXG8bT52+ gasSkr/QURYogDYGFZ0qAG4+QktMgFdPnMVZaoc0NaTWGF54k2LSyzsuWmfk/aZQHTYO imXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=z4pqoHE0ZSZsOuRJ7PSebmJfdfkZoT4YvWuUtvc7XKw=; b=QxEwjVOYOlE9Gn1I4zfUh0uSlcPz0/hv/ooOy1x0u12vypSyQWZQ4YS+KZTYY5ClGn lrCBY9WLKSeR7cQOf49/XhFY+hivC6vO7EjabpTeHVnIRm0/VKqZ6FGKNVHicV6OW6RN 6F88xomErmKs2rlCW3Aw7JCZx7gt49V1WgUA6VVW2E2nhGspEGdBqHmNg+VAD/JiJm0v a/boCCiDurlqcyARmDqBZNyYYxCX3OcwQBg5Lp2grYM6vKKu7QyVCErp+5wlgqwt5/op cNDyrdEOL/kODkfk+N8o8NaXM1AgyJiZLQo7B47sU1J1njhRhzw4hfdHCQqgS2mnqUVY MsrQ== X-Gm-Message-State: AOAM531PovCkfXwHDcMek2Sr8CZt6FVirah/aAhHPjq1iZdYwRzrWVad XiumTvCNnxCKKi6mITqlhqU= X-Google-Smtp-Source: ABdhPJwGCjd2i123EdbSA3PB1cIoIy6Uj+Bre1PoyhKbSQntGuXAUTtlmGmnQEYx8M697/zFrrV1ig== X-Received: by 2002:a19:c1d2:: with SMTP id r201mr2996071lff.148.1626090938889; Mon, 12 Jul 2021 04:55:38 -0700 (PDT) Received: from [10.42.0.5] ([188.187.60.230]) by smtp.gmail.com with ESMTPSA id z7sm1465719ljm.59.2021.07.12.04.55.38 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 12 Jul 2021 04:55:38 -0700 (PDT) Content-Type: text/plain; charset=utf-8 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: Re: madvise(MADV_FREE) doesn't work in some cases? From: Vitaliy Gusev In-Reply-To: Date: Mon, 12 Jul 2021 14:55:37 +0300 Cc: freebsd-hackers@freebsd.org, gljennjohn@gmail.com, Mark Johnston , Peter Grehan Content-Transfer-Encoding: quoted-printable Message-Id: <4C23FE3C-4FC3-41B2-9A6A-5C267CC0A0E0@gmail.com> References: <20210703065420.6dbafb5f@ernst.home> <2390FA9B-319E-45D4-BEA7-10878E43AD4B@gmail.com> <2A7A1E60-766D-427B-8288-E92B4090022E@gmail.com> To: Konstantin Belousov X-Mailer: Apple Mail (2.3608.120.23.2.7) X-Rspamd-Queue-Id: 4GNhzc4M9Mz3F40 X-Spamd-Bar: + Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20161025 header.b=ZyQ48whO; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of gusevvitaliy@gmail.com designates 2a00:1450:4864:20::12d as permitted sender) smtp.mailfrom=gusevvitaliy@gmail.com X-Spamd-Result: default: False [1.41 / 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]; MV_CASE(0.50)[]; RCPT_COUNT_FIVE(0.00)[5]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[gmail.com:+]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; FREEMAIL_TO(0.00)[gmail.com]; FROM_EQ_ENVFROM(0.00)[]; SUBJECT_ENDS_QUESTION(1.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; TAGGED_FROM(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com:dkim]; ARC_NA(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a00:1450:4864:20::12d:from]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20161025]; MID_RHS_MATCH_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_SPAM_SHORT(0.98)[0.981]; MIME_GOOD(-0.10)[text/plain]; SPAMHAUS_ZRD(0.00)[2a00:1450:4864:20::12d:from:127.0.2.255]; RECEIVED_SPAMHAUS_PBL(0.00)[188.187.60.230:received]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(0.93)[0.933]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::12d:from]; FREEMAIL_CC(0.00)[freebsd.org,gmail.com]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-hackers] X-ThisMailContainsUnwantedMimeParts: N Thanks for response, > On 10 Jul 2021, at 16:54, Konstantin Belousov = wrote: >=20 >>=20 >> After testing it looks that backing_object is not null here, memory = is not freed and mmapfork test program is still killed. Any ideas? >>=20 > I finally looked at this thing again. You do madvise(PAGE_SIZE). = With > my patch (updated version below) issue madvise() for the whole region > once. I guess madvise() should work well even with PAGE_SIZE granularity. = Usually a caller doesn=E2=80=99t need to free the whole region. As I = reported earlier madvise(PAGE_SIZE) works well in Linux and illumos.=20 Current behaviour in FreeBSD can confuse programmers and brings = impossibility to effectively give back unused memory. Also I have = another case with madvise() but with shared memory that also doesn=E2=80=99= t work (but works in Linux and illumos), will report it in new thread. =E2=80=94=E2=80=94=E2=80=94 Vitaliy Gusev