One of the golden rules when we want a high performance web site is minimize the HTTP requests. Normally we have several JavaScript files within our projects. It's a very good practice to combine all our JavaScript files into an only one file. [...] But if your project is alive and you are changing it, it's helpful to spare your JavaScript files between several files. [...] So we need to choose between high performance and development comfort.

He includes a quick script that runs through your javascript directory (recursively), grabs all of the javascript content from each, combines and minifies them to serve gzip compressed out to the browser.

Probably most of us heard about streams in PHP. They are background of all files and network operations in PHP, even if we don't see it. Everytime when you use file_get_contents or fopen you are actually using streams. But there are many stream wrappers I haven't used, because they aren't well known.One of them is compress.zlib (and two other compression stream filters).

He includes a quick example (because, thankfully, that's all working with streams like this usually requires) about pulling in a file from his server and uses the stream to fetch and unzip the data to display the contents.

There's some good advice in there, and I thought it'd be a good idea to quickly add a bit more detail about the separate approaches that Mike raises.

He goes over the APC caching, memcache, the "gzip trick", the "Not Modified" header and optimized SQL statements.

He also mentions one thing that Mike didn't mention - a split between static files (no PHP needed) and their dynamic cousins. Having a more pure Apache (no PHP installed) can help give a minute jump in speed that, depending on the size of the site, could really add up from a user's perspective.

There are 4 relatively easy ways by which you can speed up the time it takes a browser to download a page. Following on from my post on joining CSS and JavaScript files, I have written a PHP script which will automatically do all of the above.

He gives example code of the class in action and includes some screenshots of the benchmarks from the YSlow Firefox extension showing the improvements.

He illustrates the creation of simple archive that pulls in a test file from a given path. This is then pushed into the zip archive and packed down and exported. He also notes the different compression levels that it can be created with - no compression, bzipped and gzipped.

You can download the library here.

• use multi resultset queries to your database rather than many small ones
• page/object caching
• gzip compression
• tune your web server
• Don't save performance testing for the end of the project

Since the last release, there are over 20 different bug fixes resolving some annoying engine issues such as the tempval leak inside foreach(). We do not anticipate any regressions to be introduced by this RC, but I would still like to ask everyone to take a few minutes and test it against their code base. If you come across any issues please report them at http://bugs.php.net/.

You can download these latest files here:

• Bzipped version
• Gzipped version

Output buffering is a useful way to accomblish things in php like gzipping all html output and such. A while ago I wrote about it on this blog (see "A miracle called gzip") as well.

The reason I write about it again is, that I have discovered a little issue with it in CakePHP.

He notes that if you just use the ob_start with the gzip handler, debug issues arise. The soultion he's come up with, though, isn't quite as simple, but gets the job done in about ten lines and is easy to drop in anywhere.

They start with the creation of a simple data compression class, with functions to see if the browser supports gzip encoding and to get/send/compress the actual data. With the sample class created, they put it to the test with a more real-world example - echoing out user information from a MySQL database.

The groundwork is laid first, giving a simple "Hello world" example to show how the code flows. They show how the buffering system works and how to use a callback function to modify the contents of the buffer before outputting (including a full replace function to text within the buffer from an array). They follow that with a look at creating your own HTML tags and using the gzip compression functionality to speed up your pages.