On 12/12/2012 09:17 AM, Evgeny Shishkin wrote:
Actually most of low-end SSDs don't do write caching, they do not have enough ram for that. Sandforce for example.
Or, worse, some of them do limited write caching but don't protect their write cache from power loss. Instant data corruption!
I would be extremely reluctant to use low-end SSDs for a database server.
If we are talking about dedicated machine for database with ssd drives, why would anybody don't by hardware raid for about 500-700$?
I'd want to consider whether the same money is better spent on faster, higher quality SSDs with their own fast write caches.
High quality ssd costs 5-7$ per GB. Consumer grade ssd - 1$. Highend - 11$
New intel dc s3700 2-3$ per GB as far as i remember.
So far, more than a year already, i bought consumer ssds with 300-400$ hw raid. Cost effective and fast, may be not very safe, but so far so good. All data protection measures from postgresql are on, of course.