Forcing Block Size write to Centera

[Bruce_Cranksh1]

Hi All

EV 10 sp2

I have an interesting request from a customer and EMC

The customer is busy with a Centera refresh project and they want to know if EV can be configured to write to the Centera in 256 K blocks. I  can't find definitive information around how this can be done. They are using Collections and I did find this link around potential data loss if you configure the Windows Environmental Variables with  the FP_OPTION_STREAM_STRICT_MODE

http://www.symantec.com/business/support/index?page=content&id=TECH135807

But I have 3 questions around this

• If we make the change in the Environmental Variables does this mean EV writes data in 256 k blocks?
• If we make this change would it cause data loss as the customer is on a version of EV that this bug doesn't apply to
• If this change doesn't force EV to write data in 256 K blocks how would you configure EV to do this as end of the day the customer and EMC is asking for this

Thanks
 

[GCSPT]

I think I would be asking why they want to change the setting?

EV just uses the Centera SDK settings which means you set it on the EMC Node and thats what is respected by any application accessing that FP.

may be missing something !

[Bruce_Cranksh1]

Hi GCSPT

I have asked EMC to explain exactly why they want EV to write data in 256 K blocks, they did explain it to me verbally but it was complicated and I didn't understand. I'll post the reason once they explain why

But from an EV perspective is there way to do this? In all my years of configuring EV with Centera I've never come across a way make such a configuration setting

[Nathan_Clark_2 · Accepted solution]

Hi Bruce by default EV will write in 256k chunks this is the default Transfer Length for Centera SDK generic stream operations.

thanks

[Bruce_Cranksh1]

Hi Nathan

Thanks this is very relevant. Appreciate the feedback :)