From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bernd Schubert Subject: Re: LSI SAS - SSDs with DRAT and DZAT Date: Fri, 11 Apr 2014 18:57:18 +0200 Message-ID: <53481EEE.3090405@itwm.fraunhofer.de> References: <1391730975.3449.16.camel@sonic.justonedata.com> <1391806363.2761.8.camel@sonic.justonedata.com> <1391808293.2761.9.camel@sonic.justonedata.com> <1391984895.13523.13.camel@tardis.intricatesoftware.com> <1392172050.2761.37.camel@sonic.justonedata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mailgw1.uni-kl.de ([131.246.120.220]:37250 "EHLO mailgw1.uni-kl.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759563AbaDKQ5W (ORCPT ); Fri, 11 Apr 2014 12:57:22 -0400 Received: from itwm2.itwm.fhg.de (itwm2.itwm.fhg.de [131.246.191.3]) by mailgw1.uni-kl.de (8.14.3/8.14.3/Debian-9.4) with ESMTP id s3BGvKRv032720 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Fri, 11 Apr 2014 18:57:20 +0200 In-Reply-To: <1392172050.2761.37.camel@sonic.justonedata.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Kurt Miller , "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org On 02/12/2014 03:27 AM, Kurt Miller wrote: > I can report that the Samsung 840 Pro*does* support trim on the LSI > SAS2008. As suspected it supports deterministic read zeros after trim. > > One other thing to note, in my testing the P16 LSI firmware has broken > trim support. P14 and P15 report incorrect values for > /sys/block/sdX/queue/discard_granularity. P17 and P18 appear to work > fine and report correct values for discard_granularity. We are just looking for SSDs for our new compute cluster and would like to get SSDs that support trim on LSI sas controllers out of the box. Unfortunately, for a test sample of Samsungs MZ7WD240HCFV discard is not enabled by default, so probably DRAT and DZAT are missing (I can't test that right now, as 'hdparm -I' does not seem to work with devices attached to the controller). A colleague just told me that Samsung 840 Pro are also not an ideal option, as these have set overprovisioning to 0 bytes by default and there only seems to be windows tool to set it to a higher value. Not a nice idea if you want to do that for dozens or hundreds of drives. Any other suggestions for ~240GB SSDs supporting DRAT and DZAT or trim-on-lsi-sas in general? The LSI support link sent by Kurt [1] is also not perfect with respect to trim, as it lists Intel510, although we definitely know that Intel510s are disabled by default and forcing write-same trim causes data corruption (unmap works, though). Thanks in advance, Bernd [1] > http://www.lsi.com/downloads/Public/Host%20Bus%20Adapters/Host%20Bus%20Adapters%20Common%20Files/LSI_6Gb_SAS_SATA_HBA_Compatibility_List.pdf