bash$ for i in `seq 10`; do echo $i; time perl -e 'for($i=0;$i<='$i'*1000000 ;$i++){}'; done 
1

real	0m0.055s
user	0m0.048s
sys	0m0.000s
2

real	0m0.051s
user	0m0.048s
sys	0m0.000s
3

real	0m0.074s
user	0m0.068s
sys	0m0.000s
4

real	0m0.099s
user	0m0.088s
sys	0m0.004s
5

real	0m0.124s
user	0m0.116s
sys	0m0.000s
6

real	0m0.146s
user	0m0.140s
sys	0m0.000s
7

real	0m0.166s
user	0m0.164s
sys	0m0.000s
8

real	0m0.197s
user	0m0.184s
sys	0m0.000s
9

real	0m0.217s
user	0m0.204s
sys	0m0.004s
10

real	0m0.235s
user	0m0.232s
sys	0m0.000s

bash$ for i in `seq 10`; do echo $i; time php -r 'for($i=0;$i<='$i'*1000000 ;$i++){}'; done 
1

real	0m0.034s
user	0m0.020s
sys	0m0.012s
2

real	0m0.036s
user	0m0.028s
sys	0m0.000s
3

real	0m0.035s
user	0m0.032s
sys	0m0.000s
4

real	0m0.040s
user	0m0.036s
sys	0m0.000s
5

real	0m0.048s
user	0m0.040s
sys	0m0.004s
6

real	0m0.055s
user	0m0.052s
sys	0m0.000s
7

real	0m0.065s
user	0m0.060s
sys	0m0.000s
8

real	0m0.071s
user	0m0.068s
sys	0m0.000s
9

real	0m0.080s
user	0m0.076s
sys	0m0.000s
10

real	0m0.087s
user	0m0.084s
sys	0m0.000s