Adam Powell wrote:
>
> I have a mission-critical application that is basically COMPLETELY
> overloaded... the load on the server is 12 and I need to do something about
> it. I am currently using mySQL 3.22.20a - do you think upgrading to the
> latest version is a good idea or not? Is 3.
> 23 safe enough to start using?
>
> Adam
>
Adam:
There are certain issues that cannot be resolved with just an upgrade.
For example, if your tables are set up in such a way that majority of
your queries do a full table scan, an upgrade will help only if it will
help you get rid of having to scan the table.
I would recommend a careful system analysis to determine the bottlenecks
and remove them one by one. Some common problems:
- Not having an index
- Using varachar when you could have used char
- Using char when you could have used int ( eg. for an IP address)
- MySQL buffers either too big or too small
- Poorly written queries
- Not having your tables normalized
- Inefficient algorithms in the application code
Aside from that:
- Your system could be running out of RAM
- You may not have enough bandwidth to deal with your traffic
Good design and well-written code can keep you from having to upgrade.
Remember that a O(exp(n)) algorithm will not run well even on the most
powerful system in the world for reasonably large values of n.
--
Sasha Pachev
http://www.sashanet.com/ (home)
http://www.direct1.com/ (work)
