From owner-freebsd-bugs@freebsd.org Fri May 3 18:32:01 2019 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 971CE15980E0 for ; Fri, 3 May 2019 18:32:01 +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 1CBDA843DF for ; Fri, 3 May 2019 18:32:01 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id D4C8615980DF; Fri, 3 May 2019 18:32:00 +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 B234515980DE for ; Fri, 3 May 2019 18:32:00 +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 TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 43020843D9 for ; Fri, 3 May 2019 18:32:00 +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 7F7A011D68 for ; Fri, 3 May 2019 18:31:59 +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 x43IVxSb032858 for ; Fri, 3 May 2019 18:31:59 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id x43IVxW8032857 for bugs@FreeBSD.org; Fri, 3 May 2019 18:31:59 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 237636] bhyve guest ZFS filesystem freezes in zcw->zcw_cv state Date: Fri, 03 May 2019 18:31:57 +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: 12.0-RELEASE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: freebsd-bugs@morgandavis.net X-Bugzilla-Status: New 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 MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 May 2019 18:32:01 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D237636 --- Comment #3 from Morgan Davis --- The aftereffects of the issue affecting my development bhyve system sound v= ery similar to those in bug #236220, and maybe they are related. However, this issue doesn't affect 9 other FreeBSD servers w/ ZFS that I run with a similarly outfitted FreeBSD 12.0-RELEASE-p3, and many are far more heavily burdened with work in smaller RAM space. The only key difference is that this deadlock occurs only my very lightly loaded bhyve guest server. By comparison, my other systems are far more abused. One is a 2GB instance = at DigitalOcean that acts as a data backup repository. It runs MySQL as a replication server and also the endpoint for lots of rsync pushes. It's constantly churning disk I/O with 13% swap in use (due to MySQL). In additi= on, it has a cron job that regularly cycles ZFS snapshots across 33 datasets for historical archiving. Never once has it, or any others I manage, froze up l= ike my bhyve guest. The only time I need to reboot it is for FreeBSD revision updates or reconfigurations that I want to test to make sure a restart occu= rs properly. Right now, it has 28 days uptime. Given this success everywhere else except for this one bhyve guest instance, I'm not sure my issue is related to the same one affecting those in bug #23= 6220 which=20 I will try to issue the procstat command the next time this happens, but I = have found that trying to run any command from an open bash prompt usually just stalls as well. I'll omit the pipe to grep to eliminate another possible deadlock trigger. --=20 You are receiving this mail because: You are the assignee for the bug.=