Googled quite a bit but still unsure so i come back here...
What settings could I use to optimize MySQL and Apache on a server with a Quad core and 4GB RAM? Goal would be to have up to 80 simultaneous users.
The only thing I can offer is to keep in mind the following: The current stable TKL release is based on Ubuntu Hardy/8.04. The new v11.0RC release is based on Ubuntu Lucid/10.04. Apache and MySQL are installed from the relevant repos. Also keep in mind, that whilst not identical, Debian is also quite similar.
Beyond that, google is going to be more use to you than me! Although I would have a good look at the Ubuntu forums, they can often be quite handy.
Hopefully there may be other community members with ideas, or the devs may even think it a worthy idea for a blog post?
If you do find an answer elsewhere I'm sure others may be interested so please post back.
Have you already made a test load on the server? By default, it should be able to handle that amount of users simultaneously. Tuning the server is going to depend a lot on what your users are doing, ie. what table is more frequently queried, how much load you have on your server in the peak hour, etc.
So please gather some statistic info before trying to tune the server. Probably you can use it as it is by default, 80 users is not a heavy load for a Quad Core with 4GB. After you have measured the users experience, if needed, you'll now where to tune.
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