cron less than 1 min

smartguy posted this at 19:12 — 29th November 2004.

They have: 7 posts

Joined: Mar 2004

how do I set-up a cron for less than 1 minute?

Greg K posted this at 04:11 — 30th November 2004.

He has: 2,145 posts

Joined: Nov 2003

In PHP, try:

<?php
function runProgram()
{
  // THE MAIN CODE OF PROGRAM TO GO HERE
}
 
// SET THE FOLLOWING TO HOW MANY TIMES TO RUN PER MINUTE
 
$runPerMin = 1;
 
$waitTime = floor(60/$runPerMin);
 
for ($t=0; $t<$runPerMin; $t++)
{
  runProgram();
  sleep($waitTime);
}
 
?>

Keep in mind, this script will work based upon the assumption that your main programs execution takes a very minute time to execute. Now, if you are finding that the main part of the program takes 2 seconds to execute, change the one line to read $waitTime = floor(60/$runPerMin) - 2;. When you first try this, you may want to add code that checks the time it takes to execute. On my server, cron job results get e-mailed to me, so you could change the program to be:

<?php
// THIS FUNTION ONLY NEEDED FOR TIME TESTING
function microtime_float() { 
  list($usec, $sec) = explode(\" \", microtime()); 
  return ((float)$usec + (float)$sec);
}
 
function runProgram()
{
  // THE MAIN CODE OF PROGRAM TO GO HERE
}
// SET THE FOLLOWING TO HOW MANY TIMES TO RUN PER MINUTE
$runPerMin = 1;
$waitTime = floor(60/$runPerMin);
for ($t=0; $t<$runPerMin; $t++)
{
 $startTime = microtime_float();
  runProgram();
  $difTime = microtime_float() - $startTime;
 echo \"Funtion Executed in \" . number_format($difTime,4) . \" seconds<br>\n\";
  sleep($waitTime);
}
?>

This will give you the execution time each time the funtion is called. Then once you have an maximum (test it to do the max it could possibly do during a run), then take it out and adjust the subtraction.

Also check with your hosting company to see if there are limits on how long a script can run, their server may somehow cut it off or not run it at all if they limit it less than 60 seconds.

-Greg