From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takahiro Yasui Subject: Re: [RFC][PATCH] Introduce the parameter to limit scsi timeout count Date: Tue, 02 Jun 2009 16:48:06 -0400 Message-ID: <4A259006.2040203@redhat.com> References: <4A2428B5.9000701@redhat.com> <1243886558.4203.31.camel@mulgrave.int.hansenpartnership.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.redhat.com ([66.187.237.31]:52442 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750776AbZFBUpG (ORCPT ); Tue, 2 Jun 2009 16:45:06 -0400 In-Reply-To: <1243886558.4203.31.camel@mulgrave.int.hansenpartnership.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: linux-scsi@vger.kernel.org Hi James, James Bottomley wrote: > It doesn't really look like a good solution to the problem you're > describing, particularly if it's just a few isolated arrays. > > The code you propose would certainly catch things like usb devices which > are known for random timeouts; plus a lot of SCSI/ATA devices suffer > isolated timeouts because of I/O load. Global code like this could end > up offlining them. > > Which arrays are these, and what's the taxonomy of the failure ... if > TUR succeeds, perhaps there's another command for the arrays we could > send that would fail or timeout ... or perhaps there's a different way > they should be recovered. Thank you for the comments. I believe that this issue is not specific to a few storages but is a general issue on a HDD storages. Therefore, I think that adding a max timeout count on each device is one of solutions to servers which are sensitive to delay. But I got your point. I will try to find an implementation to not affect other devices. Thanks, --- Takahiro Yasui Hitachi Computer Products (America), Inc.