How come my DC machine is still relatively responsive?...

[Turbonium]

I'm running Folding at max/full capacity on a T9500 with 2GB of RAM on 32-bit Vista. Both cores are at 100% load all the time.

And yet, the system is fairly snappy and responsive. How come? I'd expect it to be laggy as a result of the CPU usage being almost totally hogged by the DC client.

I'm thinking perhaps it has to do with the priority of the client's process(es) being set to "Low" in Task Manager. If that is indeed the case, wouldn't it be better to just set the priority to "Normal" at the very least, given I'm not using the machine for anything other than Folding?

 

[VirtualLarry]

That behavior is as expected. It is achieved through the magic of CPU scheduler algorithms. There would be no point to bumping up the process priority, unless you wanted to experience lag while you were using the computer.

 

[Fardringle]

The way DC applications work, they only run when the CPU is not being used, but they make use of all available CPU cycles that are not being used by something else.

So...say you are doing something that uses 50% CPU and you have given the Folding client permission to run even while the computer is active, Folding will use the remaining 50% of the CPU cycles. And if you then do something that needs the full 100%, Folding will immediately back off and let the active program(s) use the CPU.

If you are not using the computer at all, Folding will use all 100% of the available CPU power until another program or process needs to use it. So as VirtualLarry said, changing the process priority will not make Folding run any faster, but it could easily cause problems with other programs and with the overall responsiveness of the machine.

 

[GLeeM]

If the DC program uses lots of ram ... then you could see lag while the OS frees some up for your use.

Also, GPU folding/crunching may cause noticeable desktop lag. Some apps are worse then others.

 

[Sunny129]

as a general rule of thumb, CPU computing results in a negligible amount of noticeable lag (if any at all) for the reasons mentioned above.

but as Gleem pointed out, GPU computing may not be so forgiving. this is mainly b/c BOINC can't force a GPU to only use spare/unused GPU cycles like it can a CPU. hence a crunching GPU is always using GPU cycles (and possibly some CPU cycles at the same time as well) regardless of what other programs/utilities/etc might be running/executing/etc at the same time. to make things worse, GUI lag can increase exponentially if you try to crunch on the display GPU (games, videos, or other display duties end up fighting BOINC for GPU resources).

 

[Turbonium]

Ok thanks.

If the DC program uses lots of ram ... then you could see lag while the OS frees some up for your use.

Regarding RAM: how much is enough for typical Folding WUs? I'm working on setting up some Linux boxes for Folding, but they will have only 1GB of RAM paired with fast CPUs. Is that folly?

 

[GLeeM]

Regarding RAM: how much is enough for typical Folding WUs?

I think there used to be a way to tell the client how much ram you were willing to let folding use?

 

[VirtualLarry]

have only 1GB of RAM paired with fast CPUs. Is that folly?

Might be. Does anyone know the working-set of F@H for Linux?

I've had enough problems just trying to boot a modern distro off of a disc with an X-server with only 1GB RAM.

 

[Turbonium]

Might be. Does anyone know the working-set of F@H for Linux?

I've had enough problems just trying to boot a modern distro off of a disc with an X-server with only 1GB RAM.

If it helps: the Vista system I'm currently running Folding on never really goes above 900MB total RAM usage, and Vista is supposed to be a bit inefficient with RAM, right?