From owner-freebsd-bugs@freebsd.org Sun Oct 7 22:41:19 2018 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 1F3D410AA9A3 for ; Sun, 7 Oct 2018 22:41:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 9A34E9796D for ; Sun, 7 Oct 2018 22:41:18 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id 5F41010AA99E; Sun, 7 Oct 2018 22:41:18 +0000 (UTC) Delivered-To: bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3D6EE10AA99C for ; Sun, 7 Oct 2018 22:41:18 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.ysv.freebsd.org (mxrelay.ysv.freebsd.org [IPv6:2001:1900:2254:206a::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id CED7997964 for ; Sun, 7 Oct 2018 22:41:17 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.ysv.freebsd.org (Postfix) with ESMTPS id 107F91EC82 for ; Sun, 7 Oct 2018 22:41:17 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id w97MfGh2093027 for ; Sun, 7 Oct 2018 22:41:16 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id w97MfGYU093025 for bugs@FreeBSD.org; Sun, 7 Oct 2018 22:41:16 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 232048] CURRENT: clang crashes during buildworld Date: Sun, 07 Oct 2018 22:41:17 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: marklmi26-fbsd@yahoo.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc 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-bugs@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 07 Oct 2018 22:41:19 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D232048 Mark Millard changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |marklmi26-fbsd@yahoo.com --- Comment #2 from Mark Millard --- A common reason for: c++: error: unable to execute command: Killed is being low on free RAM for too long (too many tries to get more free RAM). The console would have reported a message (that in part may be a misnomer), something like: . . . kernel: pid 1010 (stress), uid 0, was killed: out of swap space You can likely believe the "out of swap space" if you also got messages like: . . . kernel: swap_pager_getswapspace(32): failed but otherwise you may have lots of swap space but still get "was killed" messages. In part this is because FreeBSD does not swap out processes that stay runnable, so runnable processes that keep lots of RAM in the "active" status can lead to sustained periods of low free RAM (and, so, probably paging). Changing vm.pageout_oom_seq from its default figure of 12 to something larger makes FreeBSD tolerate the low free RAM longer (more tries to free RAM). Folks have use figures like: sysctl vm.pageout_oom_seq=3D120 sysctl vm.pageout_oom_seq=3D1024 on small single board computers with 4 cores (1 hardware thread per core) to allow buildworld buildkernel to complete for -j4 with 1 GiByte or 2 GiByte of RAM. I/O/storage latency for paging and swapping can contribute to needing a larger vm.pageout_oom_seq . Another thing that might help such builds use less RAM at times is to use: LDFLAGS.lld+=3D -Wl,--no-threads Using a smaller N for -jN is another example (for 1