From owner-freebsd-net@freebsd.org Sun Mar 28 21:53:12 2021 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id BB93A5B116B for ; Sun, 28 Mar 2021 21:53:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (mailman.nyi.freebsd.org [IPv6:2610:1c1:1:606c::50:13]) by mx1.freebsd.org (Postfix) with ESMTP id 4F7qG04SLSz3htG for ; Sun, 28 Mar 2021 21:53:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 8748F5B12AF; Sun, 28 Mar 2021 21:53:12 +0000 (UTC) Delivered-To: net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 8514B5B12AE for ; Sun, 28 Mar 2021 21:53:12 +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 4F7qG02g7dz3htF for ; Sun, 28 Mar 2021 21:53:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) 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 4764327858 for ; Sun, 28 Mar 2021 21:53:12 +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 12SLrCKg022892 for ; Sun, 28 Mar 2021 21:53:12 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from bugzilla@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 12SLrCoo022891 for net@FreeBSD.org; Sun, 28 Mar 2021 21:53:12 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: bugzilla set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 254333] [tcp] sysctl net.inet.tcp.hostcache.list hangs Date: Sun, 28 Mar 2021 21:53:12 +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: 11.4-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: commit-hook@FreeBSD.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@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 MIME-Version: 1.0 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 28 Mar 2021 21:53:12 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D254333 --- Comment #10 from commit-hook@FreeBSD.org --- A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=3Dcb0dd7e122b8936ad61a141e65ef8ef87= 4bfebe5 commit cb0dd7e122b8936ad61a141e65ef8ef874bfebe5 Author: Richard Scheffenegger AuthorDate: 2021-03-28 21:12:03 +0000 Commit: Richard Scheffenegger CommitDate: 2021-03-28 21:50:23 +0000 tcp: reduce memory footprint when listing tcp hostcache In tcp_hostcache_list, the sbuf used would need a large (~2MB) blocking allocation of memory (M_WAITOK), when listing a full hostcache. This may stall the requestor for an indeterminate time. A further optimization is to return the expected userspace buffersize right away, rather than preparing the output of each current entry of the hostcase, provided by: @tuexen. This makes use of the ready-made functions of sbuf to work with sysctl, and repeatedly drain the much smaller buffer. PR: 254333 MFC after: 2 weeks Reviewed By: #transport, tuexen Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D29471 sys/netinet/tcp_hostcache.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) --=20 You are receiving this mail because: You are the assignee for the bug.=