|
|
Posted by NC on 10/10/07 00:01
On Oct 9, 9:10 am, Gilles Ganault <nos...@nospam.com> wrote:
>
> A friend of mine is running a LAMP (PHP, MySQL, Apache,
> Debian) Web 2.0 site on a dedicated, hosted server with
> about 300 connected users when it's really busy.
>
> The server is an Intel Celeron 2.4 GHz with 1GB of RAM,
> a 40GB IDE drive, and a 10Mbps bandwith.
>
> Here's what top says:
>
> Tasks: 196 total, 6 running, 181 sleeping, 8 stopped, 1 zombie
> Cpu(s): 71.6% us, 8.6% sy, 0.0% ni, 58.0% id, 0.8% wa, 0.3% hi,
> 0.7% si
> Mem: 1023656k total, 963348k used, 60308k free, 119612k buffers
> Swap: 514040k total, 0k used, 514040k free, 484324k cached
>
> The site is too slow in the evenings, but we don't have
> the skills to check why and what can be done about it.
You should consider hiring someone with the skills to give you a
definite answer. Here in the newsgroup, we can hypothesize until we
turn blue, but only actual hands-on work with your application can
tell if the hypotheses we advance are anywhere near reality.
> What things would you try to see where the bottlenecks are?
> Is there some kind of check-list that we could go through?
Since your problems seem to arise during peak hours, and neither
memory nor CPU seems to be overloaded, a natural first guess is that
the holdup is with disk I/O, more specifically, in the database
interaction. What to do about it will depend on your database usage
patterns. If your application is write-intensive, you may be nearing
your hardware's capacity, and the only way to improve performance is
to upgrade the hardware (do check the UPDATE queries though; you may
be able to improve their performance by optimizing them). If your
application is not write-intensive, there are several possible avenues
to pursue: (1) optimize SELECT queries (adding an index here and there
may be necessary), (2) turn on query cache (which may help if you have
a news site, but not likely to improve things if you have a social
networking site), (3) increase mysql.max_links (which in turn will
increase your memory requirements). Do check your MySQL connection
method just in case; the best performance on a single server is
achieved by using socket connection rather than a TCP/IP connection.
Cheers,
NC
Navigation:
[Reply to this message]
|