So I've started dabbling with the "timethis()" function, figuring better to measure 1,000 iterations of the actual code than to insert a time-waster just to make some time show on the clock.

But the results are odd:

$sql = "SELECT COUNT(*) FROM theTable WHERE column = $value";
$iterations = 1000;
    $sth = $dbh->prepare($sql) or die("Could not prepare!" . $dbh->err
+str);
$exec_time = timethis($iterations, '
    $sth->execute() or die("Could not execute!" . $dbh->errstr);
    $count = $sth->fetchrow_array(  );
');
[download]

produces

timethis 1000: 26 wallclock secs ( 0.03 usr + 0.02 sys = 0.05 CPU) @ 20000.00/s (n=1000) (warning: too few iterations for a reliable count)

26 wallclock seconds but only 0.05 CPU seconds? And if I try to go to 5,000 iterations, the server returns an error.