We too use 262144 buffer size with 9940B's, and achieve in excess of 50mb/sec on exchange backups, albeit on HDS.
The blocksize limitation is a windows 2003 SP1 issue that is overcome by installing hotfix 873422, we too use the STK driver and needed this hotfix to overcome the limitation. Dave ________________________________ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul Keating Sent: 31 July 2007 14:57 To: Kevin Whittaker; veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] Exchange 2003 Information Store Backup Slow Those 9940B drives should be good for a 262144 buffer size, unless there's still some windows limitation....though I believe that limitation was for the built in windows driver. you should be fine with the STK driver, though you'd obviously want to do some testing. Can you get a report of your current disk layout from the disk fairies? RAID layout? Number of spindles? Dedicated RAIDsets? Number of paths? etc, etc? Paul -- -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kevin Whittaker Sent: July 31, 2007 9:39 AM To: WEAVER, Simon (external); veritas-bu@mailman.eng.auburn.edu Subject: Re: [Veritas-bu] Exchange 2003 Information Store Backup Slow Yes, when we speed it up we played with the buffer settings. # of buffers is set at 64, size is 32768. When I started this 6 months ago, they said only professional services could help me. But I will say that the guy that came in did help, because before it was talking 23 hours to backup. With the multiple streaming of the information stores, buffer changes, and installing the STK tape drivers for windows instead of the Veritas ones, we saw improvements. I was talking with the disk fairies and they are going to relay out the disks for the exchange servers. They are saying, from what they are seeing, this will also help with the read performance. I will just have to wait for them and be patience. Kevin ==================================================================================== La version française suit le texte anglais. ------------------------------------------------------------------------------------ This email may contain privileged and/or confidential information, and the Bank of Canada does not waive any related rights. Any distribution, use, or copying of this email or the information it contains by other than the intended recipient is unauthorized. If you received this email in error please delete it immediately from your system and notify the sender promptly by email that you have done so. ------------------------------------------------------------------------------------ Le présent courriel peut contenir de l'information privilégiée ou confidentielle. La Banque du Canada ne renonce pas aux droits qui s'y rapportent. Toute diffusion, utilisation ou copie de ce courriel ou des renseignements qu'il contient par une personne autre que le ou les destinataires désignés est interdite. Si vous recevez ce courriel par erreur, veuillez le supprimer immédiatement et envoyer sans délai à l'expéditeur un message électronique pour l'aviser que vous avez éliminé de votre ordinateur toute copie du courriel reçu. Notice to recipient: The information in this internet e-mail and any attachments is confidential and may be privileged. It is intended solely for the addressee. If you are not the intended addressee please notify the sender immediately by telephone. If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, is prohibited and may be unlawful. When addressed to external clients any opinions or advice contained in this internet e-mail are subject to the terms and conditions expressed in any applicable governing terms of business or client engagement letter issued by the pertinent Bank of America group entity. If this email originates from the U.K. please note that Bank of America, N.A., London Branch and Banc of America Securities Limited are authorised and regulated by the Financial Services Authority.
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