> From: Ray Van Dolson [mailto:rvandol...@esri.com]
> Sent: Monday, August 15, 2011 12:26 PM
> On the Intel SSD 320 Series, the spare capacity reserved at the
> factory is 7% to 11% (depending on the SKU) of the full NAND
> capacity. For better random write performance and endurance, the
> spare capacity can be increased by reducing the usable capacity of
> the drive; this process is called over-provisioning.
I have a sneaking suspicion that you'll see the greatest performance when it's
more than 50% overprovisioned. (Say, 55% or so). That will guarantee at all
times, there's plenty of unused space available, which the drive can do GC on,
even though the OS doesn't say anything like "TRIM" to the drive.
Specifically I say over 50% because 8k pages, and 4k blocks.
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