From owner-freebsd-net@freebsd.org Tue Sep 4 17:08:57 2018 Return-Path: Delivered-To: freebsd-net@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 47E38FF57DD for ; Tue, 4 Sep 2018 17:08:57 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [IPv6:2a01:4f8:d12:604::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id C6F7577B67 for ; Tue, 4 Sep 2018 17:08:56 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (eg.sd.rdtc.ru [IPv6:2a03:3100:c:13:0:0:0:5]) by hz.grosbein.net (8.15.2/8.15.2) with ESMTPS id w84H8dg1081149 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 4 Sep 2018 19:08:40 +0200 (CEST) (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: ryan@ixsystems.com Received: from [10.58.0.4] ([10.58.0.4]) by eg.sd.rdtc.ru (8.15.2/8.15.2) with ESMTPS id w84H8Q7S081391 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Wed, 5 Sep 2018 00:08:26 +0700 (+07) (envelope-from eugen@grosbein.net) Subject: Re: iSCSI issues after upgrading to 11.2 x64 RELEASE To: Ryan Moeller , freebsd-net@freebsd.org References: <541494c3-d275-dee2-ff5e-8b276ef8d9d6@gmail.com> <0C437CBE-E525-4277-9315-6205206CDBB7@ixsystems.com> From: Eugene Grosbein Message-ID: Date: Wed, 5 Sep 2018 00:08:22 +0700 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <0C437CBE-E525-4277-9315-6205206CDBB7@ixsystems.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=0.3 required=5.0 tests=BAYES_00,LOCAL_FROM,SPF_PASS autolearn=no autolearn_force=no version=3.4.1 X-Spam-Report: * -0.0 SPF_PASS SPF: sender matches SPF record * -2.3 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * 2.6 LOCAL_FROM From my domains X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on hz.grosbein.net X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Sep 2018 17:08:57 -0000 04.09.2018 23:57, Ryan Moeller wrote: >> The NIC's are Intel based using igb kernel driver: >> >> igb0: flags=8843 metric 0 mtu 9000 >> options=6403bb > > I see your MTU is 9000, and as described by the other thread you linked to, there are issues with 9k jumbo cluster allocation. > Some detailed notes are here, but the quick summary is: set MTU < 4096 > https://gist.github.com/freqlabs/eba9b755f17a223260246becfbb150a1 > >> Can anyone suggest anything to stop my system from completely locking up and becoming unresponsive? >> At the moment I'm not sure if switching to 'Stable' or 'Current' branches is a good solution? > > The problem has been mitigated for a while on 12-CURRENT, so that might be worth trying. Otherwise I’ve been hoping a committer will put this fix in 11-STABLE, but in the meantime you could manually apply the patch: > https://reviews.freebsd.org/D16534 Intel NIC users also should be aware of chip hardware problems while dealing with 9k MTU, like documented here: https://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/i218-i219-ethernet-connection-spec-update.pdf In short, Intel does not recommend MTU over 8500.