From owner-freebsd-bugs@FreeBSD.ORG Fri May 29 09:38:05 2015 Return-Path: Delivered-To: freebsd-bugs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 895F1E79 for ; Fri, 29 May 2015 09:38:05 +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 mx1.freebsd.org (Postfix) with ESMTPS id 739311605 for ; Fri, 29 May 2015 09:38:05 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.14.9/8.14.9) with ESMTP id t4T9c54Q018640 for ; Fri, 29 May 2015 09:38:05 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 200493] Killing pid 11 (idle) wedges the disk IO Date: Fri, 29 May 2015 09:38:05 +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: 11.0-CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: trasz@FreeBSD.org X-Bugzilla-Status: New X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit 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: 2.1.20 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 29 May 2015 09:38:05 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200493 --- Comment #4 from Edward Tomasz Napierala --- The reason I didn't provide more information is that I believed it to be trivially reproducible - and also because I can't tell much about it. That is, everything looks normal: the system is almost idle, vmstat/iostat/top etc don't show anything weird... It's just that "diskinfo -t" shows values orders of magnitude worse than usual. Actually, I've noticed something: idle threads priority. Before: # procstat -t 11 PID TID COMM TDNAME CPU PRI STATE WCHAN 11 100003 idle idle: cpu0 -1 255 run - 11 100004 idle idle: cpu1 1 255 run - # kill -KILL 11 [root@brick:/home/trasz]# procstat -t 11 PID TID COMM TDNAME CPU PRI STATE WCHAN 11 100003 idle idle: cpu0 0 120 run - 11 100004 idle idle: cpu1 -1 255 run - Bumping the idle thread's priority would explain what's happening. But why does it get bumped? -- You are receiving this mail because: You are the assignee for the bug.