Astropulse CPU vs GPU?

There`s a lot you can do.

Did you read the readme of the AP app ?
You are using 1 core anyways so why not running 2 instances.

I wrote some best tips how you can tweak the app.
Its included in the readme file.
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Hi, just wondering...

How many AP tasks can a GF 560Ti 1.3Gb or 660GTX 2Gb do at a time? How many CPU cores would that need?

Just want to know if it is worth waiting for Linux version of AP cuda/OpenCL.



p.s.
I'm happy with my i7-3930K CPU doing 6 AP units simultaneously producing 6 completed AP results every 13500 seconds while it is also crunching 6 GPU MB processes on above mentioned cards both doing 3 at a time. The 3930K uses Lunatics linux AVX build. CPU temperature rises to 74-79C, depending on core, when doing 6 AP simultaneously. GPU's stay at 63C.

From what I have seen, opencl task takes same amount of vide memory as the cuda task. So from purely technical angle:
560ti with 1.3 GB can hold 3 or 4 tasks
GTX660 with 2 GB will hold 8 tasks

Memory consumption doesn`t really matter here.
Each ap unit consuming almost a CPU core on nvidia cards.

More than 4 is not worth.

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While the memory of a given card may be able to "hold" a number of WU, the processor (on the GPU) can only efficiently work on two or three at a time.

If you want to try it, start with processing one WU at a time, allow the card to run through for several hours, noting the processing time for each, now repeat for two WU, three WU and 4 WU. Provided the random sample of WU you have been fed are all much the same you will see a slight increase in processing time between 1 and 2, 2 and 3 and a very large increase between 3 and 4.

You do of course need to have a feed of WU, so don't try this while the servers are "having a holiday", which they are as I type (and this holiday may well continue until about 18:00UTC (19:00 your local). I was about to start to try this on my new cruncher, but I think I'll leave that set at 1 per GPU (its a 690 which has two GPU on one card)
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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

I did try running with one core feeding the GPU about 6 months ago (with the current hardware and software set up) and the overall throughput (total tasks per hour)was less with one core set aside for feeding the GPU than having the default settings where there is a "free for all". I have no doubt that for other CPU+GPU configurations the results would be different.

(I have run GPU-X on a few occasions, and the load time (time when the GPU is essential idle, is only a few seconds - between 5 and 10, not a lot when the run time is way over a thousand).

Thats just because 1 core is not enough on AMD machines.

I finnish 2 APs in less an hour.
Thats ~3000 seconds.
You finnish in about 13000 - 15000 seconds.
Do you see the difference ?
I`m running APs over 2 years now and am fully aware of each conditions.

Claggy has also a 460 and does faster than my ATI.

Claggy, for those that don't know how to, could you post a "Janet and John" on reserving a core.
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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

You do of course need to have a feed of WU, so don't try this while the servers are "having a holiday", which they are as I type (and this holiday may well continue until about 18:00UTC (19:00 your local). I was about to start to try this on my new cruncher, but I think I'll leave that set at 1 per GPU (its a 690 which has two GPU on one card)

Claggy, for those that don't know how to, could you post a "Janet and John" on reserving a core.

Claggy, for those that don't know how to, could you post a "Janet and John" on reserving a core.

One thing i've noticed while looking at Cliff's, Rob's and spitfire_mk_2's AP results is they are all running with the default parameters,
these parameters where set like that so the app can be run on low end GPUs like 8400GS and HD5400's, and won't utilse a GTX460 or GTX660 fully,

Before you start running Multiple instances, tune the app first, this will improve GPU usage, and increase memory usage, then worry about running multiple instances,

For a mid Range GPU like a GTX460 or a HD7770, -unroll 10 -ffa_block 6144 -ffa_block_fetch 1536 is suitable,

rather than putting it in your app_info, put it in the ap_cmdline_win_x86_SSE2_OpenCL_NV.txt or ap_cmdline_win_x86_SSE2_OpenCL_ATI.txt file instead,
this has the advantage that you can change the parameters without having to restart Boinc,

The r1761 readme's have the rest of the parameters listed.

Claggy

Claggy, for those that don't know how to, could you post a "Janet and John" on reserving a core.

Easiest way is in boinc manager preferences.
On multiprocessors use 76%.
This will reserve 2 cores on a 8 core CPU.

Hi,

Thank you all for the information. I'll be waiting for a linux OpenCL AP and a x41z version of linux MB.

I'll definitely reserve a core for the GPU AP too.

As of now I'm running 6 of 12 cores doing CPU MB/AP and the other six feed the cuda MB tasks. The 6 CPU tasks run at 99,6% according to 'top' and the 6 feeding the GPU use from 6% to 10% each running on its own core.

The reason to run with these setting is that I think the i7-3930K has only 6 FPU/MMX/AVX units and when in HT the CPU processes would have to share them causing context swithing and register file store/loads and would stress the cache and memory bus.
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You can stop S@H from sending you Astoplulse quite simply.
Go to your account web page, select "SETI@home preferences", then "edit default preferences".
Deselect the two Astopluse entries, and the "allow other applications", then hit the "update" button.

____________
Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?