Addressing scalability issues in web applications

Question

This is a very general question from a newbie thinking about web application scalability. I am hosting my php based web application on a single microsoft IIS server. How do I determine how maximum number of connections that a IIS server can support without affecting performance? Also, main performance criteria for a web application in this situation would be the http response time correct ? I have a mysql database that does some expensive joins. So, my question really is - how to figure out how many max connections the server can handle? And How to speed up database performance ? I m looking for general recommendations.

Answer 1

First you need to understand what performance is acceptable to your user experience. That usually breaks down to response time of the server. If your maximum response time can not exceed 1 second for users to have a good experience, then you figure out how many queries per second the server can handle, end to end , without violating the 1 second response time for 99% of the queries. Once it violates that, its time to add more capacity in the form of servers.

Answer 2

ufff this is really generic question.

regarding the maximum amount of request the server can server. Try using some tool to stress it. I would recommend jmeter

regarding scalability:

• Use optimized indexes
• Cache much as you can: scripts, pages, images, etc.
• optimize your site

but remember that premature optimization is the root of all evil and can cost you more than you think

Answer 3

• To stress test you can use: http://support.microsoft.com/kb/231282/en-us

• For what regards the database the only way (if you want to stick with one server) is to do less query per request and maybe use materialized view (be aware of table updates at this point)

• The best of course is to cache your HTML so when users request your pages you don't need even the db connction, you just sends the html cached