LiveCD to determine latency #s (seem really low)

After having issues with my older machine I decided to try the live CD and run latency test on my newer PC.

After running the latency test for 3 hours I'm seeing both jitter numbers around 2500ns. This seems really low judging by the recorded #'s on the website. (I'm used to ~20,0000 )

Is there any difference between running the livecd latency test and the latency test after full install?

Hi

There are differences, how much they affect the values depends a lot on how much RAM you have etc.

CD access is a lot slower than HDD, so initial loads of things like Firefox will slow things down more than on an installed system.
The more RAM you have, the more can be cached and pulled from memory. You may get a big hit on the first load, but thereafter negligable.

Other systems, like graphics, networking, HID, are the same for either test.

If you are getting 2.5K with loading using the Live CD, sounds like a good candidate, do an install and confirm it

regards

That does seem low and if it holds a lot of people would be interested in exactly what the set up is.
Be sure to abuse the system by running glxgears, moving windows etc.

Rick G

Numbers creeped up a bit after a 5 hours test. This puts it inline with some of the other systems i see in the listing.

Servo thread - 5398
Base thread - 3700

Must have had 20 glxgears windows running and a bunch of other stuff

Still good.

If you post the full spec of the machine and the full latency results, I will put them on the wiki.

regards

Will do... I am going to do the full install in a bit and re-run.

I did notice during one test that my screen went blank. Not sure how this affects the tests or whether i need to, or if it is possible to disable the pc from going to sleep.

I'm not sure whether it actually went to sleep, or whether just the monitor output shut off.

Just noticed this MB doesn't have a par port card.... going to toss in the one I have on hand and see how it goes.

I'd think this will affect things negatively, but I'm not sure.

Also, for a test try running a video decode or two... make sure you're actually loading down your system, glxgears is ok for some basic testing but it's not really very heavy weight.

Are you using the default video driver or an accelerated one?