please help - files aren't running at same time

sfullman

I'll try this again, it's important that I get my server to work correctly on this.

I have a file which is basically this code:

echo time() . "<br>";
flush();
for($i=1;$i<=1500000;$i++){
	//do nothing, this is just to run the clock
}
echo time() . "<br><br>";

I call the page in my browser in 4 separate windows, at about the same time. What I have found is that the end timestamp the first window I open is basically the start timestamp of the next window, and so on.

So, my system is refusing to run more than one page at a time. Seems linux/apache/php could do better than this. Does anyone out there know the answer to this? It's worth money to me to find out ($20-30.00 easily!) thanks.

Sam

bpat1434

I'm thinking that it's your connection to your server. It can run multiple items, just probably not from the same connection. So, have you tried you and a friend accessing at the same time and comparing numbers?

~Brett

sfullman

OK, I and a coworker had IE and Firefox on our computers, and called the page in all 4 browsers. They DID run in an overlap and Linux:top tells me that httpd is running between 9-13%, BUT- worse problem now is that a process that took about 40 seconds when called by one page is now running over 20 minutes (it's still running).

Something is seriously screwed up here, I hear these wonderful stories of servers that take a million hits a day, this is NOT acceptable. Any suggestions?

Thanks,
Sam

AstroTeg

If you experiment with PHP enough, you'll find it knows not to execute a loop that doesn't have it doing any work. So the page completion times are going to be very similar to the start page because PHP skips over your for() statement.

What you'll need to do is put some work for PHP to do in the for(). One thought is to echo out the for loop counter. That'll give PHP something to do and some output you can see in your browser as to the status of its progress.

sfullman

Astro,

here's the code:

<?php
echo time() . "<br>";
flush();
for($i=1;$i<=1500000;$i++){
	flush();
	if($i/25000 == floor($i/25000)){
		echo '.';
	}
}
echo "<br>" . time() . "<br>";
?>

so you can see that I am doing something; the process takes about 55 seconds when one thread is running. But when a coworker and I did it together from separate computers (4 threads running simultaneously), it was more like 12-20 minutes -- something is screwed up.

Thanks,
Sam

bpat1434

You do realize that you are running a loop 1.5 million times. And while it may be possible to have it be done in 55 seconds when one person/computer connects to it, why do you expect to happen when more than one connects? Think about it. You're putting a crap load of strain on the server's cpu. You are running the same loop 3 million times with just two people connecting.

You had 4 connections running the same script, that's 1.5 million x 4 = 6 million itterations of the loop. While the loop may do nothing but output:
.......................
you are still straining the CPU to constantly run through the loop for each person. I don't know of any CPU that will actually handle that, except maybe a 64-bit processor, but even them I'm not so sure.

~Brett

AstroTeg

Originally posted by sfullman
Astro,

here's the code:
<?php
echo time() . "<br>";
flush();
for($i=1;$i<=1500000;$i++){
	flush();
	if($i/25000 == floor($i/25000)){
		echo '.';
	}
}
echo "<br>" . time() . "<br>";
?>
so you can see that I am doing something; the process takes about 55 seconds when one thread is running. But when a coworker and I did it together from separate computers (4 threads running simultaneously), it was more like 12-20 minutes -- something is screwed up.

Thanks,
Sam [/B]

Number-wise, that sounds about right. Although if you're wishing to test application performance, this isn't the way to go about it. You may need to rig up something that makes a bunch of page requests (and have those page requests bring back typical data or do typical operations).