You should download each of the three versions of Symfony2 in
/var/www/benchmark/sf2<X>
where <X>
is the minor version.
Then
chmod +x benchmark.sh
sudo ./benchmark.sh
AB output for each run will be found in /var/www/benchmark/results/
This was tested only with Ubuntu 12.10, your folders/URLs may vary
Also, I didn't want to push this to hardware limits as this shouldn't be a question of how many but rather how fast. If it's fast enough, the rest will follow.
Sleeps are there to allow for your hardware/CPU to catch its breath, this really is not a hardware test :)