PHP is slower than it should be

Originally, I posted this on ServerFault ... but perhaps it is more of a PHP lingual question.

I have a server with Dual Xeon Quad Core L5420 running at 2.5GHz. I've been optimizing my server, and have come to my final bottleneck: PHP.

My very simple PHP script:

./test.php

<?php print_r(posix_getpwuid(posix_getuid()));

My not-so-scientific-because-they-don't-pay-attention-to-thread-locking-but-scientific-enough-to-give-me-a-reasonable-multithreaded-requests-per-second-result scripts:

./benchmark-php

#!/bin/bash

if [ -z $1 ]; then

  LIMIT=10

else

  LIMIT=$1

fi



if [ -z $2 ]; then

  SCRIPT="index.php"

else

  SCRIPT=$2

fi



START=$(date +%s.%N)

COUNT=0

while (( $COUNT < $LIMIT ))

do

  php $SCRIPT > /dev/null

  COUNT=$(echo "$COUNT + 1" | bc)

done

END=$(date +%s.%N)

DIFF=$(echo "$END - $START" | bc)

REQS_PER_SEC=$(echo "scale=2; $COUNT / $DIFF" | bc)

echo $REQS_PER_SEC

./really-benchmark-php

#!/bin/bash

if [ -z $1 ]; then

  LIMIT=10

else

  LIMIT=$1

fi



if [ -z $2 ]; then

  THREADS=16

else

  THREADS=$2

fi



if [ -z $3 ]; then

  SCRIPT="index.php"

else

  SCRIPT=$3

fi



PIDS=""



echo '' > results

for thread in `seq 1 $THREADS`; do

  ./benchmark-php $LIMIT $SCRIPT >> results &

  PIDS="$PIDS $!"

done



for PID in $PIDS; do

  wait $PID

done



RESULTS=`cat results`

MATH="0"

for RESULT in $RESULTS; do

  MATH="$MATH + $RESULT"

done



echo "$MATH" | bc

The result of running ./really-benchmark-php 100 8 test.php is ~137 requests per second.

Running the same script on a sqlite or mysql powered instance of Drupal returns ~1.5 req/s.

I have APC and mem_cache both installed, and I have verified that they're running on defaults. (Yes, APC's enable_cli is on, also.) Does someone know the magic "make PHP execute faster" switch?

I have an alternative configuration setup (FPM/FastCGI) that serves ~140 req/s of the MySQL Drupal install... how could that be possible if PHP itself can't even serve 2 req/s from the command line?

The result of the ab tool feel just as low to me:

static page: ab -n 1000 -c 100 http://x.x.x.x/ Requests per second: 683.71

test php: ab -n 100 -c 5 http://x.x.x.x/ Requests per second: 41.38

drupal-mysql: ab -n 100 -c 10 http://x.x.x.x/drupal/ Requests per second: 0.24

drupal-sqlite: ab -n 100 -c 10 http://x.x.x.x/drupal-test/ Requests per second: 4.92