如何在PHP中追踪慢速代码

Question

I installed an open source PHP project on my Ubuntu server and got it running. However, pages load extremely slow. A phpinfo() page and a basic test page connecting to the mysql db all load very fast. There are tons of include files, log files and some curl calls in this open source code. What strategies/tools can I use to track down the source of the slowness?

Answer 1

You can use xdebug and run it through the profiler. You can visualize the profiler results via webgrind.

The following tutorials and tools will be useful:

• http://www.xdebug.org/docs/profiler
• https://github.com/jokkedk/webgrind/wiki

Answer 2

You need to profile pages, that have performance problems. It can be done with php-extension xdebug and kcachegrind .

Follow this steps:

1. Install php5-xdebug package on your Ubuntu server via: sudo apt-get install php5-xdebug .
2. Configure xdebug.profiler_enable_trigger parameter. Look at official manual .
3. Install on your local computer kcachegrind package: sudo apt-get install kcachegrind .
4. Start slow page with GET parameter XDEBUG_PROFILE=1 . See related question .
5. Copy generated profile log to your local comp and open it in kcachegrind.

Some notes:

• After php5-xdebug package installation you'll need to restart http-server (or php-fpm daemon. Depends on installed software on your server).
• Right place for profiling procedure is a test environment, not production.

Answer 3

Install debug kit

The definitive answer is to use xdebug profiling, which gives you a great amount of information as to what's happening. There is however also DebugKit .

DebugKit is a must for any CakePHP developer, and is very easy to install (it's just a plugin).

The feature most relevant to the question is the timer panel:

Knowing which part of the request is slow, will permit you to focus your attention on where the problem is.