- stripe-unit size for Windows 2008/ Exchange 2007
- Posted by Thinkpad21 on March 26th, 2008
Hi,
On a Windows 2008/Exchange 2007 SP1 Mailbox CCR Cluster ( Local disks with
RAID ), what is the best/recomanded configuration for the stripe-unit size.
Thanks !!!
- Posted by John Fullbright on March 26th, 2008
Generally, a low multiple of the IO size. 32K or 64K would be a starting
point.
"Thinkpad21" <thinkpad21@yahoo.com> wrote in message
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- Posted by Tarek Ismail on March 27th, 2008
Microsoft Exchange Server 2007 writes data in multiples of 8-kilobyte (KB) I/O operations, and I/O operation to a database can be from 8 KB to 1 megabyte (MB). Therefore, make sure that the starting offset is a multiple of 8 KB.
Failure to do so may cause a single I/O operation spanning two tracks, causing performance degradation.
If your storage vendor does not have any specific recommendations, Microsoft recommend that you use 64 KB.
--
Tarek Ismail
Infrastructure Consultant
OMS
- Posted by John Fullbright on March 27th, 2008
In Exchange 2007, an IO to the database is 8K. An IO to the logs cam be 512 bytes to 1MB. If you use a backup program that does not leverage snapshots and instead uses backupo API, then use 64K because many backup API applications read in 64K chunks. If you use snapshots, it really depends on the cache architecture of your storage. COnsult your storage vendor.
"Tarek Ismail" <Tarek_877_nospam@hotmail.com> wrote in message news:9E859CD2-EBC6-4DA3-9B94-CC56CD45708F@microsoft.com...
Microsoft Exchange Server 2007 writes data in multiples of 8-kilobyte (KB) I/O operations, and I/O operation to a database can be from 8 KB to 1 megabyte (MB). Therefore, make sure that the starting offset is a multiple of 8 KB.
Failure to do so may cause a single I/O operation spanning two tracks, causing performance degradation.
If your storage vendor does not have any specific recommendations, Microsoft recommend that you use 64 KB.
--
Tarek Ismail
Infrastructure Consultant
OMS
