topic Re: EVA 4400 Default i/o Block Size in HPE EVA Storage

EVA 4400 Default i/o Block Size

Eric v Willegen — Tue, 10 Mar 2015 08:09:33 GMT

Hi Storage-Fans!

I've got a question from a customer :

What is the Default i/o Blocksize of a new created Vdisk? The want to align this OS-partition with the i/o blocksize of the Vdisk.

I've searched for this but cannot find any info about this.

Maybe someone can give me some additional info?

Thanks
Eric
Netherlands

P.S. This thread has been moevd from Disk, Disk Arrays (Retired Discussion Board) to Storage Area Networks (SAN) (Enterprise). - Hp forum Moderator

Re: EVA 4400 Default i/o Block Size

Uwe Zessin — Mon, 09 Nov 2009 17:12:39 GMT

The internal "chunksize" of previous generations was 128 KBytes. As far as I can tell, the size of the x400 series was not made public - maybe it is the same.

For the first-generation series 3000/5000 there was a customer advisory that suggested to align the partition to a 64-block (32-KByte boundary) to prevent a performace loss in some special write-intense VRAID-5 situations. It was claimed that alignment was not necessary in later products.

Of course it does not hurt if you do it anyway. On a Microsoft page it was written that they do not agree with "some vendor claims" that alignment did not improve performance.

Re: EVA 4400 Default i/o Block Size

Eric v Willegen — Tue, 10 Nov 2009 09:34:54 GMT

Thanks Uwe for this information. Do you have a link to the Customer Advisory you've mentioned?

Thanks

Re: EVA 4400 Default i/o Block Size

Uwe Zessin — Tue, 10 Nov 2009 09:45:45 GMT

Wow, they've moved it from the old Compaq system (PSD_OI040301_CW02) to the c9-system *and* it is still online *and, extra bonus* the database was able to recall it on the first try:

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c01204487