After my clustering experiments which you read about in my last post we were capable of handling more than a 1000 concurrent visitors. We will see if the current growth can be managed by this clustering on the 4 systems currently running the site. It is clear to me now that the bottleneck was actually the MySQL, not the web part. Switching off the second webserver makes no difference, while switching off the second MySQL will completely stop the site from responding. So I removed the one webserver and the site is running on 3 webservers now.
The MySql installation has been tweaked for absolute performance with all the tricks in the books, but it cannot do more than it it doing now on that hardware. I need to figure out a way to see, in the next concurrent userbarrier, which part of the system needs improvement. I will think about it; if anyone has an idea; let’s have it (put a comment please).
My next projects are;
– make a seperate site for chat and use that instead of the current chat (dunno which chat yet; have to find a nice one still)
– make a seperate site for the forum and use that instead of the current forum (probably phpbb)
– making a MySQL/PHP cache for the database queries on the current site
– fixing the master-slave replication so it won’t fail if the master fails
More on this subject… Later.