Sebastian Bergmann has posted the results of some benchmarking on the compilation he's done on the branches of PHP from version 3.0 all the way up to 5.3-CVS.

As people keep asking me for an update to my previous benchmarks (PHP / GCC / ICC Benchmark, PHP 5.1 / GCC Benchmark (Update), and PHP 5.1 Performance, I quickly ran a new benchmark today.

He rendered the results out into a series of charts defining the number of total seconds taken for the compile and how long each of the components took. It's impressive to see how much of a jump there was between the 3.0 series and 4.3.

He also includes his compile settings (and machine information) as well as the numbers for the results if you'd like to graph them out yourself.

On Nexen.net today, Damien Seguy presents some numbers on something that there's not a lot of research done on - the number of servers running multiple PHP versions.

This subject was hot at the birth of PHP 4 (running PHP 4 and PHP 3, or course), and it is coming back with a vengeance for PHP 5, backed by the immense user base of PHP 4. If PHP 5 is the default installation in 2008, what will happen to all those users? [...] Based on this observation and my earlier experience of cohabitation, I wondered if there was any indicator of multiple PHP installation.

He used the same tracker he implements for his normal monthly stats and ran a modified query to get the numbers of multiple-version servers that are out there. He's graphed some of the results. Based on his results, though, he notes a market for multiple PHP installations but "a pretty small one", noting that you're probably better off making the jump out to PHP5 anyway.