Databases: Afraid of SSD?
. I didn’t discuss this with my clients until recently, when one client just asked me straight away: “As SQL tuning guy, are you afraid of SSD because it kills your job?” Here is what I told that client.
.. If you want to get the factor 50 speed-up of SSDs, you’d better avoid reading large chunks of sequential data, because that’s where you can only gain a factor five improvement. To put that into database context: if you are doing many full table scans, you won’t get the full potential of SSD. On the other hand, index lookups have a tendency to cause many random IO operations and can thus benefit from the fast response time of SSDs. The fun part is that properly indexed databases get better benefits from SSD than poorly indexed ones. But guess who is most desperately betting on SSD to solve their performance problems? People having proper indexes or those who don’t have them?