tembow had an idea to open up discussions with those interested in the community to explore ideas in optimizing the www.castlecops.com performance.

Obviously some questions will be asked, so here are some basics...

All the deamons are the latest version for PHP, Apache and MySQL (5.2.5, 2.2.8, 5.1.22rc-log respectively).

Obviously we'll probably be revealing information that I may not be comfortable with. That can give criminals a look into our environment. But, I figure lets take a chance.

Let the questions/suggestions begin, and hopefully we'll reach a positive conclusion. I appreciate the help folks volunteer here.

One item that deserves mention:

• Most of the static files have been moved to another server and daemon (lighttpd) to reduce main site load. However, the IRT snapshots have always resided on yet another system and daemon (thttpd).

Do you have any suspicions what could have happened, what changes have been made recently, that caused this slowdown?

83ppm 27.712s (15.736s) to post
72ppm 45.572s (45.015s) to redisplay

Cudni

While I'm not sure if this would even help, perhaps consider updating the forum software, such as to phpBB version 3 (or is this phpBB 3) or IPB?

Dunno if it would help though, just a thought.

Just noticed this thread and it's actually related to a recent blog entry I posted recently: http://www.gena01.com/forum/gena01_blog/performance_tips_apc_vs_eaccelerator-t201.0.html

To add a couple of things:
1. Install Eaccelerator or APC or any other PHP caching extension. This is a must. This will save PHP script recomplication time per request. Also if you are using eaccelerator you can increase the shared memory size (if you have enough memory on the server). This will greatly improve things as they will be cached in memory and not re-read from disk.
2. I just did a quick YSlow check and it gave the post reply page a D 65 score. The most common and probably the easiest thing to fix is adding Expires header that sticks for a number of days to the images and CSS. I am not sure how to do this for other web servers but in apache you can enable mod_expires and set the expiration in either .htaccess file or in the global apache config by content-type.

These are just some quick tips since I don't know the website details or the technology and server specs on the back-end.

Thank you,

Gena01

[quote="Cudni"]Do you have any suspicions what could have happened, what changes have been made recently, that caused this slowdown?[quote]
Sounds like a silver bullet question, but unfortunately the answer isn't one.

- Squid removed
- OS upgraded
- Daemons all upgraded

I've disabled services and loads really haven't changed.

@Gena, this is one I didn't know:

log-queries-not-using-indexes

As for slow queries, the percentage of them compared to all comes out to 0%.

For webpages there are two factors that result in slow performance:
1. Long running scripts on the server which delay loading of HTML.
2. Lots of content that needs to get downloaded by the browser. The less HTTP requests that are made the faster things show up.

I found this thread with a quick google search: http://www.phpbb.com/community/viewtopic.php?t=135383

Some ideas that could work:
1. Check if phpBB supports caching. I know some boards will detect if APC or Eaccelerator is installed and will integrate with it to cache things a bit better. I know SMF has a whole section that allows me to control how much caching is going to be done.
2. There could be some things database related and since I don't know where the bottleneck is it's hard to say. If you are using MySQL enable slow query log and see which queries are causing the problems.
3. This has been mentioned in the SMF support forum related to MySQL specifically in this thread: http://www.simplemachines.org/community/index.php?topic=50217.0
It mentions that if you are using MyISAM tables and there's lots of concurrent users and posts happening it could help to convert tables to InnoDB.

Good luck.

Gena01

Using InnoDB should not impact read times. It wil also help with the writing. Overall table level locks are a very very bad thing.

There are also a number of other great mysql tools:
1. MyTop - MySQL Top script
2. MySQL Report -- this one I used before and it has very nice reporting functionality that can optionally provide even more details.

In one of the replies to the blog post above I posted a link to some slides that cover MySQL performance and tuning.

Gena01

Also found something that could help: http://www.phpbb.com/bugs/phpbb2/ticket.php?ticket_id=2591&sid=7ee54485f60b4084f168e700ba213ce7

Seems that this is a possible reason and something to try as well.

Gena01

I've been using mytop for a while, very nice tool indeed instead of having to use show full processlist, etc.

Running it now.

As for innodb, I don't recall what the loss is over myisam. I'll go fish for that mysql dev link.

Just found some benchmarks of Innodb vs MyISam vs Falcon (new storage engine being developed in 5.1)
here: http://www.mysqlperformanceblog.com/2007/01/08/innodb-vs-myisam-vs-falcon-benchmarks-part-1/

Gena01