From nobody Sat Oct 07 00:02:42 2023 X-Original-To: bugs@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 4S2QTt4S70z4w5MG for ; Sat, 7 Oct 2023 00:02:42 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4S2QTt38bxz4W3g for ; Sat, 7 Oct 2023 00:02:42 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1696636962; a=rsa-sha256; cv=none; b=gRrE8eXdp0djjb2hwfDzEYCAoIc2uisJmZ63EKJQnC8dp2ALWFPNjLRAwjasyDH+kEcZ+4 mS8A02jAOIOpcQ9kUfiZwWJ+5b0bxRbX8X6LNEFI+9NubCGrzmvuNiWcI7pKrUTtS3VdHg ObK8pNXCI9BIp86jgb8qtNyNDs5AO9P6e5YT0O9E2SuxSw/EOmGJVIuRnGpviAmf/8Htat j/YlMQDquGk5zsCNpIVlYgSi20NRETF8B2nBXuxqo8pHNB8q/us8h11QPIldo/6WaTKfAi ycM8n1OsXrLByHmnvMym3kBq/kngVH964RmvuWkhSU9J2oKSCY+oN6eVGc2n9g== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1696636962; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ScuhFTOJEZjNhGls8qigD5SQpqpBOwEZUUpFbpf2W74=; b=kVjlkg53pRgVRakgKd4WaFsBz/0PwpEYm91T2+X1kHY2QRq6R/32B9VxVh4R5s0CxKsTKd 71Dzv5bC991jWzJEt4fMSvxhjY7LEQcfCTLl07rYOP6Oj6rMVS2B+6ErQrigUM5TGjW7hb GuLjvd6W3OrrRnp1Y/cyvZRqzYS0aOZ/9f4g4BjqXGfNx601BIcCY3Shvg/G4IXIDIq1NH vXjCw3dvS3K4FmxvnENLWYDHAGH7J6M7Qj0SMm4zUI0VKAYEp0UJN0C3U2CWqTNfLjKifA kH5qwWC7q5E3AO2hZqRvLhWyDm0ekHe9bq1NmnqBeqZ+Sry5PfgwSLGsxX3oGg== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4S2QTt2D2Tz17Qk for ; Sat, 7 Oct 2023 00:02:42 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 39702gA0041657 for ; Sat, 7 Oct 2023 00:02:42 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 39702gZx041656 for bugs@FreeBSD.org; Sat, 7 Oct 2023 00:02:42 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 274316] excessive memory consumed by static_single_cpu_mask Date: Sat, 07 Oct 2023 00:02:42 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: emaste@freebsd.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@freebsd.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D274316 --- Comment #2 from Ed Maste --- We can switch to run-time sizing for these, but there's a very interesting observation used by Linux that we can adopt, to significantly reduce the me= mory used. We have (currently) MAXCPU count of cpuset_ts, each with one CPU set. Note = that all but one of the longs making up each cpuset_t is zero. If n=3D__bitset_words(MAXCPU) then cpuset_t is an array of long __bits[n]. = If we have (n-1) long zeros, 0x1, (n-1) long zeros, 0x2, (n-1) long zeros, and so= on, with an appropriate offset we can use that same 0x1 for: 0000000000000000 0000000000000000 ... 0000000000000000 0000000000000001 0000000000000000 0000000000000000 ... 0000000000000001 0000000000000000 ... 0000000000000000 0000000000000001 ... 0000000000000000 0000000000000000 0000000000000001 0000000000000000 ... 0000000000000000 0000000000000000 and so on for 0x2, etc. --=20 You are receiving this mail because: You are the assignee for the bug.=