Adaptive Flash Cache

[mujzeptu]

So now we are seeing more and more about this in official HP quickspecs and such, and it is indeed coming very soon in the latest firmware....

My question is, does anyone know what the requirements are? I have a V400 with 4 disk shelves. Do I have to add a magazine to each shelf (4x4=16 SSDs) to use adaptive flash cache, or could I add say 1 magazine of 480GB SSDs (4x480GB) and just put that one magazine in one of the shelves and have it be used for adaptive flash cache?

What other potential restrictions or gotchas do I need to consider?

[vPatrick]

AFC ist part of 3PAR OS 3.2.1 and is licensed with the base OS. You need at least 4 SSDs for a StoreServ 7000 and 8 for a 10000. This implies that AFC will not be available for F- and T-Class systems.

[mujzeptu]

Ok great, so 2 magazines for the V400 (4 ssds per mag) would suffice.

Thanks!

[3ParDude_1]

I have put all the details I received from HP on Advanced Flash Cache in my blog http://3pardude.com/2014/09/22/adaptive ... deep-dive/. Unfortunately there were no specific details for the V series. Although as Vpatric stays its bundled as part of the OS and I have seen no announcements that 3.2.1 will not be available to the V class. Again as Vpatric said the minimum number of disks was 4 or 8 per node pair for the 7 and 10 thousand respectively, so I would guess it will be similar to this but cannot guarantee it.

[vPatrick]

@ 3ParDude_1

Already read your article. Keep on blogging, I like your blog.

@ mujzeptu

That's right. How many enclosures has your V400?

[mujzeptu]

It has 4 enclosures.

[3ParDude_1]

vPatrick thanks

[bajorgensen]

I've heard rumors that not all SSDs are created equal.
I guess we will get more details when it is out of controlled release.

[Cleanur]

480GB cMLC is not supported for AFC as it doesn't have sufficient reserve space to provide 5 years endurance at the level of writes required by a full blown caching solution. Look ahead and think why would there be a need to implement raid protection on a read only cache....just a theory but maybe it won't always be just read.