Hi Adam,
What Greg and Chris are referring to is the SSD write cliff aka write
amplification:
- https://flashstorageguy.wordpress.com/tag/write-cliff/
- https://en.wikipedia.org/wiki/Write_amplification
This and the MTBF are the main reasons to choose enterprise grade SSDs
over consumer grade SSDs.
Especially if your SSDs are used by many (4+) spinning disks, as the
write cliff phenomenon will occur earlier.
Regards,
Frédéric.
Le 26/04/2017 à 16:53, Adam Carheden a écrit :
What I'm trying to get from the list is /why/ the "enterprise" drives
are important. Performance? Reliability? Something else?
The Intel was the only one I was seriously considering. The others were
just ones I had for other purposes, so I thought I'd see how they fared
in benchmarks.
The Intel was the clear winner, but my tests did show that throughput
tanked with more threads. Hypothetically, if I was throwing 16 OSDs at
it, all with osd op threads = 2, do the benchmarks below not show that
the Hynix would be a better choice (at least for performance)?
Also, 4 x Intel DC S3520 costs as much as 1 x Intel DC S3610. Obviously
the single drive leaves more bays free for OSD disks, but is there any
other reason a single S3610 is preferable to 4 S3520s? Wouldn't 4xS3520s
mean:
a) fewer OSDs go down if the SSD fails
b) better throughput (I'm speculating that the S3610 isn't 4 times
faster than the S3520)
c) load spread across 4 SATA channels (I suppose this doesn't really
matter since the drives can't throttle the SATA bus).
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