CEP2. How much memory really?

[OldChap]

I have always been cautious about running too many Clean Energy threads at once but as there seems to be little else to run I decided to take a look at memory use.....

Linux Mint 64 Cinnamon here and the System monitor is showing 31 threads using 5.7GB. ???

I thought that it is supposed to need a GB per thread??? It still says that on: https://secure.worldcommunitygrid.or...ame=minimumreq

Anyone got any input on this? Does it use more as the wu's progress? (currently I have progress between 9 and 69%)

[anubis]

Im waiting for my queue of 40 DSFL WUs to finish. If this is really true then

[Evantaur]

i believe 1GB is the worst case scenario

[anubis]

When i was running win7x64 it used everything with my 12c 6gb system and swapped as hell, almost killed SSD, that i know.

[fallwind]

Mem usage is highly variable with CEP2 and 1GB per thread is recommended. You'll also need a descent SSD (or RAM drive) dedicated to the BOINC data folder if you plan to run more than 4 or 5 threads at a time. This is from my experience with Windows machines, YMMV with Linux.

I had one of my 12 thread rigs set up with 24GB of RAM, half dedicated to system memory and the other half to a RAM drive containing the BOINC data folder. It crunched 12 threads of CEP2 no problem but as with any windows machine, it would occasionally lock up or crash and I'd have to re-install BOINC.

[D_A]

I found it was similar on my Linux machines. Very memory hungry and insanely swappy. Not system swap though, directly to the BOINC data folder. There was quite a bit of talk on the WCG forums about setting up RAM drives on Linux for it but I didn't pay too much attention as I didn't have the RAM to do it.

[Evantaur]

I had one of my 12 thread rigs set up with 24GB of RAM, half dedicated to system memory and the other half to a RAM drive containing the BOINC data folder. It crunched 12 threads of CEP2 no problem but as with any windows machine, it would occasionally lock up or crash and I'd have to re-install BOINC.

You only need to ramdrive your slots directory, that's where all those heavy writes are happening

[Mumak]

I just checked the memory usage on W7 x64 and it varies between 100-250 MB per CEP2 thread, peak usage was 310 MB.
I'm not sure if a RAM drive can improve disk access, since when there's free memory, Windows uses it for file buffers anyway.

[D_A]

CEP2 doesn't behave like you'd expect. It's not the amount of RAM each unit requires that's the problem, it's the amount of data it caches during the course of the unit. CEP2 is known to write substantial amounts of data to it's own work directories during the course of each unit. This is unaffected by any settings for swap or page file usage since it has nothing to do with either. By the way, by "substantial" I mean up to 24GB per unit. When running more than a couple of units at a time it can severely lag the IO system with the hard drive being the major bottleneck. The project has been known to eat early SSDs due to the volume of writes to storage. Running it with the data directory on a good SSD was found to make a substantial improvement in efficiency and running in a RAM drive better again, significantly more so that with any other WCG project.

[nanoprobe]

Each CEP2 task can read/write as much as 32GB of data. That's why I personally do not use SSDs when running it. Raising the "write to disk every xx seconds" in BOINC settings can help reduce the strain but it will take longer for the task to complete. Default is 60 seconds. I use 300 for CEP2.