Hello all.
I noticed some comments of zoneminder, like:

http://ask.slashdot.org/comments.pl?sid ... d=30446182
http://ask.slashdot.org/comments.pl?sid ... d=30451890
http://ask.slashdot.org/comments.pl?sid ... d=30448240

They insinuate that zoneminder needs a some beefy cpu's.

Anybody know why zoneminder might be viewed as cpu expensive, or what's going on here?
Thanks!
-r

Motion detection requires that every frame is compared to the previous one(s) according to one or more user defined zones and rules.

When you have streams doing 20-30 frames per second, colour high quality image sizes of 1280x1024 and multiple cameras - then yes, zoneminder does need some grunt to get its job done.

It does not follow that there is anything from with the design or programming of Zoneminder.

It is not about the motion detection you are asking but you can try to lower the cpu usage of the zm system with the use of libjpeg-turbo library (replacing the default one in linux). There is a big difference with and without the library. There is an info in the zm forum.
http://sourceforge.net/projects/libjpeg-turbo/

Has anybody done any comparisons of ZM versus motion cpu usage? (that turbo jpg looks awesome, BTW).

-r

Fedora 14 will ship with libjpeg-turbo incorporated

http://fedoraproject.org/wiki/Releases/14/FeatureList

I forgot about the turbolib, thanks storm. Indeed, makes a bit difference and good to see it's getting into at least one distro.

I also suffer from extremely high CPU usage (> 2.0 with 2 cameras@320x240 - and it increases by more than 1 for each camera I add)
This is on a fresh Ubuntu Server 10.10 install

I have used motion for years, and the same setup could handle 8 cameras under Motion with no real noticable CPU load. I have a co-worker with the exact same results as me.

Other than the turbo jpg library, does anyone have any other suggestions?

Yeah, check the load on your harddrives, with iotop or something, they tend to slow down the system and increase the load.

Also, already said, but really give a try to libjpeg-turbo.

Ok I have made great progress. It turns out that from the ubuntu zoneminder package, after the install it doesn't set all the permission appropriately and found out that the www-data user wasn't added to the video group so apache or zoneminder didnt have access to /dev/video. Even sifting through the /var/log/messages or /etc/apache2/error.log, it had slipped by. The issue that I am having now is when I setup the cameras using /dev/video0-3 and using all the channels 0 and 1, I am getting duplicates on half the screens. I have swapped many channels and cant get all seven cameras on different screen

Debian.

I massively reduced system load when going from Ubuntu to debian with just zoneminder running, exact same config.

I also have had perfomance troubles by using Ubunut 10.04. The process Xorg was very cpu intensive. CPU usage about 80%! I found out that there are problems by using Intel graphic cards like i845/i855 Now I usea a nVida graphic card and the cpu usage is about 20%

Maby it's the same with Ubunut 10.10