troublesome

[davidbam]

[mention]Bryan[/mention] That sounds interesting. Would you happen to have a link please for how to do this under Linux?

How does boincmgr figure out which to connect to when both are on localhost?

[Bryan]

They run separate and independent. On one you enable your CPU project and on the other you enable GPU. If you attach to the same project, ie PG, then the project will see it as two different computers with both having the same name.

The method for setting up multiple BOINC clients is on TSBT somewhere ... I have trouble finding stuff like that. Maybe Alez can find it

EDIT: I found the one for Windows ... if someone can't find one for LInux then I'll write one up.

[davidbam]

My GTX 1080Ti does a little over 3M/day on PG and 10M/day on Collatz. The highest paying project on PG is PPS Sieve.

I finally got some Collatz work for nVidia by having a machine dedicated to running GPU (no CPU work). Using a GTX960 at the moment but I'll build a machine capable of taking both this and the GTX1080

My question is therefore, with 2 non-identical cards will I see two collatz_sieve_1.40_x86_64-pc-linux-gnu__opencl_nvidia.config files to allow me to optimise them independently ?? Maybe I should wait and see what happens and only optimise them after both are running together

[Alez]

Nope, only 1 collatz_sieve_1.40_x86_64-pc-linux-gnu__opencl_nvidia.config.

[Bryan]

I hear it is difficult to get multiple GPUs that aren't identical to run in Linux. I can't speak from experience on this.

If you can get it working where BOINC recognizes both cards then you can setup 2 BOINC instances with a instance controlling only a single card. Then you can have 2 config files available.

[davidbam]

I should probably learn to crawl before I start trying to run. Either that or sell/buy hardware to reduce variety

[davidbam]

Next question is whether the speed of CPU materially affects the performance of the GPU?

Background : I couldn't get nVidia card working in a Xeon / x79 motherboard (more questions on that later), so I moved it into an old HP machine (Pentium G3250 processor). This works but I am underwhelmed by the first results - it would maybe manage 220,000 credits per day on Collatz. Is it maybe related to the number of PCI lanes supported by CPU ??

Out of interest, an ageing ATI/AMD r7-350 in the HP machine manages about 340,000 per day on Collatz

[Bryan]

Yes, the speed of the CPU can affect the results a GPU gets. As you mentioned the PCI lanes etc but it is more the processing speed.

Most GPU projects also use the CPU. The CPU gets things ready and then passes it to the GPU to crunch. When the GPU finishes crunching that batch it contacts the CPU to get the next batch. This happens over and over until the WU is totally finished.

I have 2 GTX 1080Tis in different machines. One is in a I7-3930K running at 4.2G w/ PCIe 2.0. The 2nd is in a E5-2683 V4 server running at 2.7G w/ PCIe 3.X. The GPU in the I7 machine always outperforms the other GPU even though it has PCIe 2 vs PCIe 3.

Also remember that on most GPU projects you need to reserve some CPU threads otherwise the GPU winds up waiting to be serviced by the CPU.

[davidbam]

This file is collatz_sieve_1.30_windows_x86_64_opencl_nvidia_gpu.config andwill be empty. Linux will obviously be slightly different name

Is anyone crunching Collatz on nVidia under Linux please? I am beginning to think that Collatz doesn't use CUDA & that Linux drivers don't support OpenCL on nVidia.

I'd be DELIGHTED to be proved wrong though

[davidbam]

scratch that - I have that running myself on one machine.

Config file is called : collatz_sieve_1.40_x86_64-pc-linux-gnu__opencl_nvidia.config proving that opencl is used

It is only doing about 225K credits per day on Collatz though (unoptimised and fitted in a fairly old machine)

ETA : I can't remember which boinc client I loaded as I see there is a boinc-client-nvidia-cuda. Back to the drawing board