djk at tobit.co.uk
Thu May 8 13:40:01 BST 2008
Steve Sims wrote:
>> MySQL 5.1 is great product and I'm quite certain these days you
>> wouldn't run into the problems you've talked about.
> I *did* test out with MySQL 5 (which I believe was still beta), and this was
> executing the queries in question in 6s, but suffered from exactly the same
> scaling issues. So if I deployed it I would still have had the same
> problems. I needed a solution there and then...
The real issue with MySQL scalability is to do with which backend engine
one uses. If you were using 3.1 then you were using MySQL native isam
tables (there being no choice at the time) - these are OK *provided* you
have enough RAM to hold the whole index in memory. With eight tables +
indexes, I don't imagine this requirement held. Hence the crappy
This limitation is, IMHO, one of the reasons behind MySQL going
multi-backend. In effect you now have (at least) three storage engines,
each with a common front end. Each of these engines have completely
different scalability / speed characteristics and tradeoffs.
More information about the london.pm