Writing a perl script that will use 100% of 1 cpu is pretty simple:

perl -e'while(1) {$x++}'
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If you also need to exercise memory and paging, you could have something like:

perl -e'$x=" " x 1024 x 1024 x 256; while(1) { $x=~s/ /./g; $x=~s/./ /
+g;}'
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Are you shooting for something more precise, like 30% cpu load? That would be much harder to fine-tune...

Mike,
Have you ever looked at (tye)Re: one-liner hogs? Fun!

Cheers - L~R

Limbic~Region,

No, I hadn't.

But I'm glad you pointed me to them, they're quite lovely!

Of course, if some poor sap runs Procs as root, or on a system without process limits, his day's going to be ruined... :)


Mike

Since we're talking Windows here, the OP needs to use double quotes in the first case, and to reverse single-for-double and vice-versa in the second...

perl -e "while(1) {$x++}"

perl -e "$x='' x 1024 x 1024 x 256; while(1) { $x=~s/ /./g; $x=~s/./ /g;}"

Interestingly, at least to me, in the second case I saw the handle count rise rapidly (well, over the course of a few tens of seconds), with "Available" physical memory actually increasing (mostly, there were a few small dips). That seems counterintutitive.

If the intent is to create a large string, '' x 1024 x 1024 x 256 isn't working:

C:\test>perl -wle "$x='' x 1024 x 1024 x 256; print length( $x )"
0
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A null string isn't the same a string containing a null. And 0 * anything is 0. Try

C:\test>perl -wle "$x = chr(0) x 1024 x 1024 x 256; print length( $x )
+"
268435456
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Personally, I find even that a little dubious in that, due to precedence, it creates the final string in 3 stages rather than 1. I think that

C:\test>perl -wle "$x = chr(0) x (1024* 1024 * 256); print length( $x 
+);<>"
268435456
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is 'better', though it has little effect on the outcome.

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

I found this thread in search today so will post the two scripts I created.

# CPU consumption loop

$p = 0;   # number of processes (0 => 1 process)
$w = 20;  # amount of work per iteration (20)
$t = 0;   # sec of think time between iterations (0)

for (1..$p) {fork()} while (1) {for($x=0;$x<$w*100000;$x++){sin($x/($x
++2))} if($t){sleep($t)}}
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------------------------------------------------

# Memory consumption loop - defaults consume 1GB in 3 min on i7-620m

$i = 3000;   # size of increase (3000)
$t = 1;      # sec think time between increases (1)
$r = 150;    # time before reset (150)
$c = 5;      # sec before next climb starts (5)

@chars=('a'..'z','A'..'Z','0'..'9','_');
while (1) {
  for(1..int(rand($y))) {$rs.=$chars[rand @chars]}
  for($x=0;$x<$i;$x++){$z[$y,$x]="$rs"x(int(rand($x))*2)}
  $y++;$rs='';sleep($t);if($y==$r){@z='';$y=0;sleep($c)}
}
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