From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH] scsi: Set the minimum valid value of 'eh_deadline' as 0 Date: Wed, 09 Oct 2013 11:38:51 +0200 Message-ID: <5255242B.8040404@suse.de> References: <524C48AC.2010901@suse.de> <1381304600-7862-1-git-send-email-renmx@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from cantor2.suse.de ([195.135.220.15]:38855 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136Ab3JIIhE (ORCPT ); Wed, 9 Oct 2013 04:37:04 -0400 In-Reply-To: <1381304600-7862-1-git-send-email-renmx@cn.fujitsu.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Ren Mingxin Cc: jbottomley@parallels.com, linux-scsi@vger.kernel.org, emilne@redhat.com, joern@logfs.org, james.smart@emulex.com, bvanassche@acm.org, roland@purestorage.com On 10/09/2013 09:43 AM, Ren Mingxin wrote: > The former minimum valid value of 'eh_deadline' is 1s, which means > the earliest occasion to shorten EH is 1 second later since a > command is failed or timed out. But if we want to skip EH steps > ASAP, we have to wait until the first EH step is finished. If the > duration of the first EH step is long, this waiting time is > excruciating. So, it is necessary to accept 0 as the minimum valid > value for 'eh_deadline'. > > According to my test, with Hannes' patchset 'New EH command timeout > handler' as well, the minimum IO time is improved from 73s > (eh_deadline =3D 1) to 43s(eh_deadline =3D 0) when commands are timed > out by disabling RSCN and target port. > > Another thing: scsi_finish_command() should be invoked if > scsi_eh_scmd_add() is returned on failure - let EH finish those > commands. > D'accord. Looks like a valid case. I'll be merging it to my original patchset, seeing that James _still_ hasn't responded to it, let alone merged it. Sigh. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html