topic Is 4GB cache sufficient for P6300EVA performance? in Disk Enclosures

Is 4GB cache sufficient for P6300EVA performance?

Venkat_DXB — Wed, 04 Jan 2012 07:27:02 GMT

I have proposed P6300 EVA to my customer. It has 4GB cache. HP Continuous Access will replicate data to another P6300 EVA at DR site over IP WAN link of dedicated 16 Mbps. The normal rate of replication is expected to be in the range of 400 Kbps to 800 Kbps with the peak replication rates going upto 2Mbps (rarely) with the amount of data changes happening in the primary array. The servers host SAP application and Oracle DB servers for ERP as well as Exchange and Symantec Enterprise Vault. Exchange replication is NOT array based, while SAP and EV make use of EVA CA.

Can someone tell me if 4GB cache is sufficient for managing the array performance taking into account the routine IOPS of servers as well as the replication? OR should I propose P6500 EVA so that I can have 8GB cache?

Thanks in advance.

Re: Is 4GB cache sufficient for P6300EVA performance?

anuj123 — Wed, 04 Jan 2012 08:52:29 GMT

Yes 4 GB is fine. Go ahead with that.

Re: Is 4GB cache sufficient for P6300EVA performance?

Venkat_DXB — Wed, 04 Jan 2012 09:12:50 GMT

I am not sure Anuj,, I see that you are a HP BTO specialist .... most of your discussions are around topics that re;ate to that area... I would prefer to wait for a more professional opinion of a storage expert on my topic

Re: Is 4GB cache sufficient for P6300EVA performance?

Johan Guldmyr — Wed, 04 Jan 2012 10:39:47 GMT

Hello Venkat, I'm not sure. It would be nice if there were any whitepapers or best practices in regards to this, have you looked in the HP SAN Design Reference Guide or on www.compaq.com/storage/whitepapers.html ?

Some things I believe make a difference:
whether you are going to use asynch or synchronous replication?
how are you going to connect the arrays over IP?
delay / response time over the link
only one IP WAN link? will you be able to load balance / use exchange based routing?