@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
I'm planning the build on a new server. I originally intended on putting 8 x "900GB 15K RPM SAS 12Gbps 512e" drives into a RAID 10 config using an H740P adapter, but then I saw that there are quite a few options for SAS SSD. I haven't really learned too much about the differences of putting SSD in RAID and how it compares to HDD in RAID, so I wanted to see if anyone here (Scott) had any input on the matter.
Example: Would it be worth putting, say, 6 x "1.6TB SSD SAS Mix Use 12Gbps 512e" drives into a RAID 10 instead? Is there a better approach with SSD in RAID?
RAID 6 is the way to go. We lost a server after replacing a drive and it's RAID 10 pair decided to drop out about 5 to 10 minutes into a rebuild.
In our comparison testing 8x 10K SAS drives in RAID 6 has a mean throughput of 800MiB/Second and about 250-450 IOPS per disk depending on the storage stack configuration.
SAS SSD would be anywhere from 25K IOPS per disk to 55K-75K IOPS per disk depending on whether read intensive, mixed use, or write intensive. There are some good deals out there on HGST SSDs (our preferred SAS SSD vendor).