Re: Reliability with RAID 10 SSD and Streaming Replication

On 5/22/13 11:05 AM, Merlin Moncure wrote:
> unfortunately, I don't have a s3700 to
> test with, but based on everything i've seen it looks like it's a
> mostly solved problem. (for example, see here:
> http://www.storagereview.com/intel_ssd_dc_s3700_series_enterprise_ssd_review).
> Tests that drive the 710 to <3k iops were not able to take the 3700
> down under 10k at any queue depth.

I have two weeks of real-world data from DC S3700 units in production
and a pile of synthetic test results. The S3700 drives are at least 2X
as fast as the 710 models, and there are synthetic tests where it's
closer to 10X.

On a 5,000 IOPS workload that crushed a pair of 710 units, the new
drives are only hitting 50% utilization now. Does that make worst-case
10K? Maybe. I can't just extrapolate from the 50% figures and predict
the throughput I'll see at 100% though, so I'm still waiting for more
data before I feel comfortable saying exactly what the worst case looks
like.

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