Easy, Fast, Cheap Way to Generate CPU Load?

jsailor asks: "A large client and their engineering team will be evaluating cabinets and their ability to cool high density blade server deployments. Some of these systems can consume upward of 21 kW per rack and accordingly require a lot of airflow and/or liquid systems to cool. The systems actively monitor heat conditions, increase airflow rates, and can throttle CPU speeds if necessary. What we need is an easy, fast, and cheap way to run the 2-way and 4-way blades at or near peak CPU utilization for extended periods of time so thermal analysis can be performed. Ideally, we would be able to boot them off a CD and have some means of monitoring the CPU on each or even setting the level of CPU utilization we'd like them to run at. Please note that we do NOT need to simulate a real world application and disk and network access are not of much concern. While running your favorite compute-intensive project is a nice idea, we need something simple so I've come to the Slashdot community for assistance. What are your thoughts?"

Comments

A Heater.

[Anonymous Coward]

Why not stick a heater in the cabinet that also consumes 21kW of power?

quite simple

[timdorr]

`yes`

A little hack someone showed me a while ago. Just set that in the startup script and away you go! Eats up memory and CPU time, so you'll end up with a very very high load and disk activity to boot.

How about Netbench?

[msoftsucks]

A few years back Ziff Davis released some decent benchmarking tools. The ones for file serves were called Netbench You can set up different tests that exercise different aspects of file servers. With just a couple of PCs you can create significant load that would peg the CPU utils to 100% for a whole weekend. Although these tools are no longer supported, they still work quite well.

md5sum

[jacobdp]

md5sum < /dev/urandom

/dev/urandom produces an infinite stream of random data - just pipe that throgh MD5 for some nice numerical CPU load. Not disk- or network-bound either.

Linpack

[verycoldpenguin]

On a serious note, linpack (http://www.netlib.org/linpack/) You can run as many processes as required for your machine (i.e. 1 process per cpu) and with care you can use as much memory as you want (memory gets really hot and takes a lot more power than most people think). I do development testing for manufacturers who want us to sell their kit, I have burnt out many (now the manufacturers believe me that they are underspec'd) power supplies by using a well tuned linpack run to overload the system. It will take a bit of compilation to get it right for your system I suspect, but it can really heat a room up (got exhaust temps >60 celcius on some machines).

Re:Endless fork?

[flink]

#include <stdio.h>

int main( int argc, const char** argv )
{
/* program */
printf( "\n\nHit any key to quit." );
getchar();
return 0;
}