Re: Reliability with RAID 10 SSD and Streaming Replication

On 5/22/13 3:51 PM, Merlin Moncure wrote:
> s3700 is rated for 10 drive writes/day for 5 years. so, for 200gb drive, that's
> 200gb * 10/day * 365 days * 5, that's 3.65 million gigabytes or ~ 3.5 petabytes.

Yes, they've improved on the 1.5PB that the 710 drives topped out at.
For that particular drive, this is unlikely to be a problem. But I'm
not willing to toss out longevity issues at therefore irrelevant in all
cases. Some flash still costs a lot more than Intel's SSDs do, like the
FusionIO products. Chop even a few percent of the wear out of the price
tag on a RAMSAN and you've saved some real money.

And there are some other products with interesting
price/performance/capacity combinations that are also sensitive to
wearout. Seagate's hybrid drives have turned interesting now that they
cache writes safely for example. There's no cheaper way to get 1TB with
flash write speeds for small commits than that drive right now. (Test
results on that drive coming soon, along with my full DC S3700 review)

> btw, cost/pb of this drive is less than half of
> the 710 (which IMO was obsolete the day the s3700 hit the street).

You bet, and I haven't recommended anyone buy a 710 since the
announcement. However, "hit the street" is still an issue. No one has
been able to keep DC S3700 drives in stock very well yet. It took me
three tries through Newegg before my S3700 drive actually shipped.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
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