We aren't sure whether to use software MDRaid or a MegaRAID card.
We're buying some new Postgres servers with
2 x 240GB Intel SSD S4610 (RAID1 : system)
4 x 960GB Intel SSD S4610 (RAID10 : db)
We'll be using Postgres 11 on Debian.
The MegaRAID 9271-8i with flash cache protection is available from our
provider. I think they may also have the 9361-8i which is 12Gb/s.
Our current servers which use the LSI 9261 with SSDs and we don't see
any IO significant load as we are in RAM most of the time and the RAID
card seems to flatten out any IO spikes.
We use MDRaid elsewhere but we've never used it for our databases
before.
Advice gratefully received.
Rory
[A previous version of this was sent to the PostgreSQL performance list]