From owner-freebsd-bugs@FreeBSD.ORG Tue Oct 2 08:00:27 2012 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 81E661065690 for ; Tue, 2 Oct 2012 08:00:27 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id 67ED58FC16 for ; Tue, 2 Oct 2012 08:00:27 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.5/8.14.5) with ESMTP id q9280RWE082836 for ; Tue, 2 Oct 2012 08:00:27 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.5/8.14.5/Submit) id q9280Rug082824; Tue, 2 Oct 2012 08:00:27 GMT (envelope-from gnats) Date: Tue, 2 Oct 2012 08:00:27 GMT Message-Id: <201210020800.q9280Rug082824@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Eugene Grosbein Cc: Subject: Re: kern/172166: Deadlock in the networking code, possible due to a bug in the SCHED_ULE X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Eugene Grosbein List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Oct 2012 08:00:27 -0000 The following reply was made to PR kern/172166; it has been noted by GNATS. From: Eugene Grosbein To: Alexander Motin Cc: bug-followup@FreeBSD.org, eugen@eg.sd.rdtc.ru, Andriy Gapon Subject: Re: kern/172166: Deadlock in the networking code, possible due to a bug in the SCHED_ULE Date: Tue, 02 Oct 2012 14:59:31 +0700 02.10.2012 14:53, Alexander Motin пишет: > On 02.10.2012 10:48, Eugene Grosbein wrote: >> 02.10.2012 13:58, Alexander Motin пишет: >>> About rw_lock priority propagation locking(9) tells: >>> The rw_lock locks have priority propagation like mutexes, but priority >>> can be propagated only to an exclusive holder. This limitation comes >>> from the fact that shared owners are anonymous. >>> >>> What's about idle stealing threshold, it was fixed in HEAD at r239194, >>> but wasn't merged yet. It should be trivial to merge it. >> >> Would it fix my problem with 6-CPU box? >> Your commit log talks about "8 or more cores". > > Hmm. Then I see no reason why threads were not stolen, unless they are > bound to specific CPU. Check `sysctl kern.sched.steal_thresh` output to > be sure. All NIC's threads and dummynet are bound in my boxes. igb(4) in RELENG_8 bounds its threads by default in very wrong way, so I rebound them. dummynet(8) in RELENG_8 goes wild under severe load unless bound to single or two cores. kern.sched.steal_thresh: 2