On 05/16/2012 01:01 PM, Merlin Moncure wrote:
Although your assertion 100% supported by intel's marketing numbers, there are some contradicting numbers out there that show the drives offering pretty similar performance. For example, look here: http://www.anandtech.com/show/4902/intel-ssd-710-200gb-review/4 and you can see that 4k aligned writes are giving quite similar results (14k iops) even though the 710 is only rated for 2700 iops while the 320 is rated for 21000 IOPS. Other benchmarks also show similar results.
I wrote something talking about all the ways the two drives differ at http://blog.2ndquadrant.com/intel_ssds_lifetime_and_the_32/
What the 710 numbers are saying is that you can't push lots of tiny writes out at a high IOPS without busting the drive's lifetime estimates. You can either get a really high IOPS of small writes (320) or a smaller IOPS of writes that are done more efficiently in terms of flash longevity (710). You can't get both at the same time. The 710 may ultimately throttle its speed back to meet lifetime specifications as the drive fills, it's really hard to benchmark the differences between the two series.
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