In this new post Patrick Allaert offers a solution that can help speed up the inclusion of files via the Composer autoloader (in addition to the already present "optimize-autoloader" option).

The problem with the classmap strategy and the nature of PHP is that there is no (easy) way to have a persistent variable across requests containing the classmap. [...] This [large returned array of mappings] can even take a big portion of your request's response time when you have hundreds or thousands of classes like it is the case with eZ Publish 5 being based on Symfony, where about 2 600 classes are involved.

He suggests something that could be included into the Composer functionality itself - creating symbolic links in the PSR-0 standard to the location of the files to make it easier for Composer to resolve their location (based on namespace, not having to find them). Some sample code is included showing an additional autoloader that then uses the vendor names to match the path directly.

In this quick post to her blog, Lorna Mitchell shares an interesting bit of benchmarking she did between PHP versions 5.3 and 5.4, finding 5.4 twice as fast as it's previous version sibling.

So recently I was working on some benchmarks for different versions of PHP, because I heard that PHP 5.4 is "faster" and since I'm a data geek I want to know how much faster! Now, PHP 5.4 is, in general, faster than PHP 5.3 but not twice as fast* unless you pick a use case which has been particularly optimised. My first attempt at benchmarking the two versions produced this. This was a surprise to me; was PHP 5.4 really so much faster??

Her benchmark was a pretty simple one - looping and creating a new object, evaluating the timing of how long it took to execute. A commentor also points to some more official benchmarks that were done and posted to the php.internals mailing list.

The Agile Toolkit blog has a new post today that looks at speed in PHP frameworks the their relative speed (no, there's no benchmarks here).

This question is often asked, but is never answered properly. So how to measure framework speed? Let me also explain why "scalability" is more important than general "performance". [...] This along with a general overheads of the framework greatly contributes to the "slowness" of your project. So how can framework contribute to performance of your project?

They touch a few different ways that frameworks can help execute things a bit faster like:

• Make Fewer SQL Queries
• Selective render
• Parallelization
• Overheads
• Caching

In this new post Joseph Scott takes a look at hashing in PHP, specifically around md5 hashes, and a better alternative (that's also more secure.

The majority of the Coding Horror: Speed Hashing post talks about speed based on MD5. [...] If you are still using MD5 to hash passwords (or worse, aren't hashing passwords at all) then please stop and go use bcrypt. For those using PHP phpass is a great option.

He talks about the crypt method, how its encryption method and "cost" value effects the speed and how difficult it would be to generate all possible hashes for a password (hint: crypt with a cost of 13 is worlds better than md5).

In this new post to his blog Joshua Thijssen describes something that can help when processing large amounts of data (like, in his example, the text of a book) to search through the information and find if a certain piece of data is in the set - a bloom filter.

Most of my co-workers never really heard of bloom filters, and I'm continuously need to explain what they are, what their purpose is and why it's a better solution than other ones. So let's do an introduction on bloom filters. [...] Bloom filters have the property of being exceptionally fast AND exceptionally small compared to other structures but it comes with a price: it MIGHT be possible that our bloom filter thinks that an element is inside our set, when it really isn't. Luckily, the reverse is not possible: when a bloom filter says something is NOT in the set, you are 100% sure that it isn't part of the set.

He explains how the filter works, noting how it's better for memory consumption and how it's possible for it to give a "maybe" response instead of ab absolute "yes" or "no". He also points out a PHP extension, bloomy that takes the hard work out of it for you.

In response to a previous post benchmarking exceptions, Volker Dusch has posted some of his own thoughts and benchmarking results on the same topic.

Some days ago there was a blog post regarding php exception performance in 5.4 and the numbers got reported all over the place. The actually numbers are secondary. The main point is: Don't trust "random" stuff on the Internet when thinking about improving your application performance. You always need to measure things for your self and take care doing so! I've initially trusted the benchmark myself and disgraced the whole post saying: "Well yes, exceptions are slower than if statements but nice that they got faster".

He includes some results with a bit more standardized testing - one run with both 5.3 and 5.4 using XDebug and another with it turned off for both. His results make sense, if you think about them:

So what we learn from that? Running stuff with debugging tools is slower than not doing that. That's why we don't use xDebug in production.

On DZone.com John Esposito reminds you about another technology Facebook has introduced to the world of PHP (besides HipHop) - XHProf, a PHP profiler.

Facebook did more for PHP: they also created XHProf, a PHP profiler with a (supposedly) easy-to-use HTML interface, designed to pinpoint exactly where your bottlenecks are appearing, so that you can optimize at every stage in the pipeline. [...] If you haven't tried XHProf, you might want to look into it. Installation apparently requires a little nudging, but Nick Lewis just posted a full, practical guide to benchmarking and performance tuning your PHP and MySQL, using XHProf (as well as other techniques) -- a very nice overview of many common bottlenecks and how to open them up.

There's also a link to some Drupal 6 benchmarks that shows how it has helped that project (including both small and large improvements).

In a new post from Derick Rethans he talks about an extension version of Twig, the popular templating engine from the creators of the Symfony framework.

A while ago, Fabien asked me to have a look at porting one of Twig's slowest methods, TwigTemplate::getAttribute(), into a PHP extension. It is a complex method that does a lot of different checks and look-ups. Fabien's benchmarks showed that this method was responsible for quite a large amount of time. On top of that, it didn't seem that it could be optimised any further as PHP code itself.

He points to the twig-ext extension that's a reworked version of the "getAttribute" method from the tool and the performance gain (about 15%) it gives. Compiled templates will automatically call this new method in the extension. This update has already been merged into the main Twig repo.

Derick Rethans has a new post to his blog today talking about some work that's been done to speed up XDebug's code coverage generation. Changes in the coming 2.2 release have some improvements that make things perform better and put less stress on PHP in the process.

Code coverage tells you how much of your code base is actually being tested by your unit tests. It's a very useful feature, but sadly, it slows down PHP's execution quite a lot. One part of this slowdown is the overhead to record the information internally, but another part is because I have to overload lots of opcodes. (Opcodes are PHP's internal execution units, similar to assembler instructions) They are always overloaded even if code coverage is not used, because it's only safe to overload them for the whole request.

These changes were from a combination of contributions from Taavi Burns and a new ini setting that will allow you to enable or disable the code coverage in XDebug. Benchmarking shows a good amount of time reduction in coverage runs - dropping anywhere from a few seconds to over a minute. He also mentions the idea of "modes", shortcuts to predefined settings for different types of reporting (like "profiling" or "tracing").

Sometimes a little (external) testing of your website is in order and Gagan Chhatwal has posted his list of ten tools you can use to check everything from how much load the site can take to what can be done to optimize the load time.

When maintaining or running a website , Webmasters need to keep in mind that one of the pertinent issues they will need to focus on is :Website Testing, which is not only vital for the website itself but for the user as well and one should not overlook its importance. [We have] collected some vital and free website testing tools which will help Webmasters in testing their sites thus saving users to conduct time consuming needless searches in finding the best resources pertaining to Web related tools and info.

Among the tools on the list are services like:

• Load Impact
• Browser Mob
• Host Tracker
• Built With
• CSE HTML validator

Most of these resources are free services, if not then they have a trial where you can see if it's a good fit.