VMAX Meta Members Best Practice

8 meta members should be enough for performance considerations with VP.  Powers of 2 were a very good idea with thick volumes but is not important for VP volumes. 

what are VP voulmes?

And for best performance, the VP (TDEVs or thin) metas should be striped.  Concatenated metas can be expanded easier, but they will have lower overall performance.

VP = Virtual provisioning volumes (thin).  You mentioned TDEVs which are VP volumes.

You will get better overall performance from striped metas.  Yes the backend is already striped, but IO to a single meta on the front-end can still restrict performance, even with 100% cached IO.

If you won't ever need to expand the meta, use striped metas.  If ease of expansion is more important than performance, use concatenated meta volumes.

As the tdevs are already striped on back end data devices, is it okay to stripe again for the metas, rather than going for concatenated Metas ?, isn't striping on striping  a issue ?, help me understand.

Thanks,

two levels of stripping accepted, like RAID5 makes the first  , striped metalun makes the second  part ad  creating a file system with striping makes the third one( we avoid the third layer of stripping) ; yes there is a little confustion on scenario like while using Oracle ASM( which again striped internally)

Too many levels of striping is a bigger concern for traditional non VP volumes.  For best performance on VP volumes you should use striped metas even though that could be the third level of striping in the Symmetrix.  (RAID =1, VP = 2 META = 3 ), they will have higher performance than a concat meta, but are harder to expand.

Yup. :-)

Metas on thick provisioning have to fit into the backend, this is why the powers of 2 were important.  Since VP metas have nothing to do with the backend layout at all, there is no such need.  A 5 member meta may perform slightly better than a 4 member meta in some cases, and would be fine.  However there is nothing wrong with sticking with powers of 2, since they would also work fine.

I'm John Adams, and for VP, any # of members is OK.  4 or more may be needed for performance reasons, but more than 16 will probably not add any additional performance.

You are John Adams and you approve your message at EMC World ?

Ahhh, I should have picked up on the Quincy reference. Thanks for the info and good to "chat" with you again!

Are there any rule-of-thumb numbers for how large a single TDEV should be before going with a striped meta ... assuming high performance requirements? The "blueprint" document I referred to before has a chart for this but would like to get you opinion on it.

dynamox - love the campaign commercial reference!

A RAID1 thick volume is not striped.  A RAID 1 VP pool is striped.  A thick RAID 1 meta volume can be striped.

Do you consider RAID1 as striping?