On 4/4/2014 5:29 PM, Lists wrote:
So, spend the money and get the enterprise class SSDs. They have come down considerably in price over the last year or so. Although on paper the Intel Enterprise SSDs tend to trail the performance numbers of the leading consumer drives, they have wear characteristics that mean you can trust them as much as you can any other drive for years, and they still leave spinning rust far, far behind.
Another issue to bear in mind is that SSD performance may not be consistent over time. This is because the software on the drive that manages where data lives in the NAND chips has to perform operations similar to garbage collection. Drive performance may slowly decrease over the lifetime of the drive, or worse : Consumer drives may be designed such that this GC-like activity is expected to take place "when the drive is idle", which it may well be for much of the time, in a laptop. However, in a server subject to a constant load, there may never be "idle time". As a result the drive may all of a sudden decide to stop processing host I/O operations while it reshuffles its blocks. Enterprise drives are designed to address this problem and are specified for longevity under a constant high workload. Performance is similarly specified over worst-case lifetime conditions (which could explain why consumer drives appear to be faster, at least initially).
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