1 VG vs multiple ?

Hi,

I'm using LSI megaraid 9266 controllers and a modest number of 10 x 1TB seagate constellation 7200 rpm drives + 1 240GB SSD forCachecade pro.
My storage clients are ESXi 5 servers running mainly websites on a LAMP stack.

I would like to obtain good performance, so some questions:
=> any advise on the best stripe size to pick ? (default = 256kb)
=> raid5 (9 disks raid5 + 1 hotspare = 8TB) vs raid6 (10 disks = 8TB) ? Or go for raid 10 (5TB) ?

On each DSS V7 I would like the following volumes:
- 3TB iscsi
- 2TB iscsi
- 3TB "other" (snapshots ..)

=> do I just create one big 8TB virtual drive on my LSI controller or would it make sense to create 3 virtual drives there and to have 3 different unit's exposed in DSS instead of 1. Any difference / (dis)advantages ?

Thanks !

256k strip is fine, but you can test with others to see which you prefer. This can depend on the data file sizes used.
RAID 10 will be best performer.

no advantage to multiple units. Typically the only time I see this is when it is required. For example different RAID sets all on the same controller.

One advantage to smaller units is if you lose an entire volume then a smaller number of users are affected. Had a RAID 10 volume lose a drive and while rebuilding, its mirror pair drive died. Lost entire 10 TB volume. Ouch!