On 11:17 Sat 07 May , Joachim Durchholz wrote:
Am 07.05.2016 um 02:27 schrieb Lana Black:
Hi Mikhail,
Have you considered external database engines? I suppose you could benefit from using Redis in your case.
Wikipedia says that while Redis can use the disk as "virtual memory", that feature is deprecated, so it definitely expects to keep the whole dataset in memory. Which kind of defeats the whole point for Mikhail.
I believe we're talking about different things here. This page [1] says that disk persistence is a standard feature in redis. Furthermore, my employer uses redis as a storage backend for raw video, and it works just fine. But yes, redis might not be the best choice depending on what data Mikhail works with.
sqlite comes to mind. HDBC claims to have a driver for it, and it's linked into the application so there would be no additional setup required.
If Mikhail already has another database in his application, the setup cost is already paid for, and he might want to check whether that's fast enough for his purposes. I'd expect postgresql or mysql to be too slow, but H2 to work just fine. Of course that's just expectations, so testing would be needed.
It is certainly possible to get 2k requests per second with postgresql [2] on a fairly limited hardware if network latency is taken out of the picture. Again this heavily depends on the kind of data and other conditions. [1] http://redis.io/topics/persistence [2] https://gist.github.com/chanks/7585810