Folding Forum

I only have a dual-core machine, and even on light mode, FAH eats over half of the available CPU power. This is not good for a machine that's also used to run other calculations in the background. Is there a way to make it so the light mode would actually be light, and instead be limited to 1 thread, or even better, half a thread?

Folding@Home is somewhat time-critical in that one work unit depends on a previous folder's work, so the work can't be partitioned into entirely arbitrary pieces. Many work units also benefit from multi-threading. There is a way to run half a thread, but I suspect you won't complete the work unit within the timeout limit if you do that. If your laptop is already heavily processing to the point that the heat output is annoying, then perhaps you shouldn't fold on it. I only fold on my MacBook Pro when it's sitting on a cooling pad and is doing light work - not when it's doing video editing or other heavier workloads.

PS: Do you have a passcode? (https://apps.foldingathome.org/getpasskey)

Welcome to Folding@Home!

As you see, there are three settings:
Light uses 1/2 of your CPU threads
Medium uses all but one of your CPU threads
Full uses all your CPU threads

So on a dual core computer, there is not a lot of difference. (There are also changes to GPU usage, but the MacOS does not allow GPU usage)

Thee is also a more detailed setting in the Advanced Client where you can set exactly the number of threads (F@H calls them CPUs) you want to use, but again there are not many ways to divide two.

If it is a dual-core machine with two threads per core, F@h should see four CPUs. In the advanced settings of FAHControl, you can set a parameter with a key of "cpus" and a value of "1" to use a single thread. I can't provide explicit directions on how to do this because I don't use FAHControl. Instead, I have set this line in "/etc/fahclient/config.xml":
I also don't know where this file is kept on Mac OS, but I hope that this information is still helpful.

The number of CPU threads is set in the advanced control (FAHControl) by clicking Configure, selecting the Slots tab, clicking Edit on the CPU slot, and then adjust the number on the top, which is -1 (auto-select) by default, then click OK and click Save.

On MacOS the config file is found here:

gunnarre wrote:The number of CPU threads is set in the advanced control (FAHControl) by clicking Configure, selecting the Slots tab, clicking Edit on the CPU slot, and then adjust the number on the top, which is -1 (auto-select) by default, then click OK and click Save.

On MacOS the config file is found here:

Code: Select all

/Library/Application\ Support/FAHClient/config.xml

Thanks, this should be pretty useful.