Hi I own my one deidacated server with intel Xeon on 2.4GHz and 4 giga of ram. My site works perfect when the number of concurrent users is under 250. But when it get more then 250 the site is very slow. the processor run under 1%. I try to increase php memory_limit and some other thing but no lack,
Any advice how to fix this?
Thanks a lot.
Howdy,
Typically when things like that occur, you’d need to spend some time in the code of your application, determining what exactly it’s doing that’s causing things to slow down at 250 concurrent users.
It’s often something related to the database queries it’s performing, but that’s what you’d need to dig into.
Alternatively, you could also implement caching of some sort.
For example, using memcache can significantly reduce database lookups, and will often greatly increase the performance of your application.
-Eric
Well i write the php files to cache and no sql is run because the site is read from the cachet files. so I think this is not the problem. BUT I think because i store more picture in one folder (1000 pics) is this can be some problem .
My biggest issue is what can I do on server site to make the site go more smooth. and more fast.
Howdy,
Yeah, unfortunately, scaling can be a difficult problem to solve 
It’s not always an issue of just tweaking the server end… sometimes what the code itself is asking the server to do is too much, once enough users are hitting the server.
And that’s where code profiling comes in – code profiling is the process of benchmarking the code to figure out where exactly the bottlenecks are.
You could certainly be right about it bring related to having too many files in one directory, that’s capable of causing performance issues at a certain point.
The simplest way to fix that would be to use multiple directories for storing your pictures, rather than fitting all those files into one directory.
It can be tough to determine what exactly to fix… that all comes down to the specifics of your server, and what exactly your application is doing. But something like code profiling can help narrow down the problem.
But if you think it’s the pictures, then you could always start by breaking those up into multiple smaller directories and see if that makes a difference.
-Eric
I have found this article for optimizing web server so you can all take a look.
http://www.ibm.com/developerworks/linux/library/l-tune-lamp-1/