EVA 8K Disk partition alignment.

[Louis Henninger_1]

We purchased two EVA5000's 2C12D systems 3 +years ago. We upgraded the controllers 18 months ago to EVA 8K using "data in place" strategy.Since I wasn't around for the initial install, I can't be sure that the disks created on the EVA5K was aligned on 64K boundary. Could this continue to be a problem even after upgrading to the 8K controllers running XCS 6.0? The blocks would still be misaligned since they could have been created not using best practices, right? is there anyway to check? and what's the default block size for the EVA using Windows 2K3?

[Sheldon Smith · Accepted solution]

First, according to the "HP StorageWorks 4x00/6x00/8x00 Enterprise Virtual Array configuration best practices white paper":

"Old best practice: Microsoft DiskPar utility is required for optimum Windows performance with the EVA.

"Previous versions of EVA firmware poorly handled the case when transfers were not 2K-aligned. This alignment requirement was eliminated with the 5.xxx versions of XCS. The use of DiskPar neither enhances nor detracts from EVA sequential performance."

So if you are running XCS 6.0, "misalignment" is now a non-issue.

Second, I'm not sure what you are asking about regarding default block size for the EVA. There is no way to set a block size (PSEG aka Physical SEGment) on the EVA. Are you asking about something else?

[Louis Henninger_1]

Maybe instead of block size I should have asked about stripe size.

[Sheldon Smith]

If you are asking about setting the size of anything *on* the EVA itself, other than the size in GB of the visible LUN, you can't.