It was PAP... Running with debugging mode *off* yields much better results ! Still with completely vanilla install , only getting [req] => 5000 [parallel] => 10 [total] => 50000 [start] => 1178820825.99 [stop] => 1178820836.79 [period] => 10.791821003 [req_s] => 4633 [req_m] => 277988 [req_h] => 16679298 localhost to localhost using #!/usr/local/php/bin/php <?php $stats['req'] = 5000; $stats['parallel'] = 10; $stats['total'] = $stats['req'] * $stats['parallel']; $stats['start'] = microtime(true); echo(exec("/usr/local/freeradius-cvsfast/bin/radclient -q -p {$stats['parallel']} -c {$stats['req']} -f users 127.0.0.1 auth testing123")); $stats['stop'] = microtime(true); $stats['period'] = $stats['stop'] - $stats['start']; $stats['req_s'] = round($stats['total'] / $stats['period']); $stats['req_m'] = round(($stats['total'] / $stats['period'])*60); $stats['req_h'] = round((($stats['total'] / $stats['period'])*60)*60); print_r($stats); ?> and with make CC="gcc -O3 -mcpu=970 -mtune=970 -mpowerpc64 -mpowerpc-gpopt" Setting CC / CFLAGS at configure time doesn't seem to work ... -- Arran Cudbard-Bell (A.Cudbard-Bell@sussex.ac.uk) Authentication, Authorisation and Accounting Officer Infrastructure Services | ENG1 E1-1-08 University Of Sussex, Brighton EXT:01273 873900 | INT: 3900