I have recently been looking into improving PHP performance for a website. I found the following benchmarks as part of my research:
http://forum.lxcenter.org/index.php?t=msg&th=16233
| PHP Config | Requests/sec | Avg Latency |
|---|---|---|
| mod_php | 187.31 / sec | 26.694 ms |
| ruid2 | 206.21 / sec | 24.248 ms |
| itk | 20.20 / sec | 247.583 ms |
| suphp | 13.25 / sec | 377.221 ms |
| suphp + worker | 20.83 / sec | 240.016 ms |
| suphp + event | 20.74 / sec | 241.092 ms |
I ended up using PHP-FPM, which gave me about 10% lower latency than ruid2 above using PHP 5.6.