Guy Rouillier wrote:
Scott Marlowe wrote:
I assume you're talking about solid state drives? They have their
uses, but for most use cases, having plenty of RAM in your server will
be a better way to spend your money. For certain high throughput,
relatively small databases (i.e. transactional work) the SSD can be
quite useful.
Unless somebody has changes some physics recently, I'm not understanding
the recent discussions of SSD in the general press. Flash has a limited
number of writes before it becomes unreliable. On good quality consumer
grade, that's about 300,000 writes, while on industrial grade it's about
10 times that. That's fine for mp3 players and cameras; even
professional photographers probably won't rewrite the same spot on a
flash card that many times in a lifetime. But for database
applications, 300,000 writes is trivial. 3 million will go a lot longer,
but in non-archival applications, I imagine even that mark won't take
but a year or two to surpass.
One trick they use is to remap the physical Flash RAM to different logical addresses. Typical apps update a small percentage of the data frequently, and the rest of the data rarely or never. By shuffling the physical Flash RAM around, the media lasts a lot longer than a simple analysis might indicate.
Craig
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