ATI AstroPulse released

I was in the process of writing these questions when the beginning of the major air condition outage struck. They were very fresh then, and (after editing down a few, mostly still interesting, at least to me).

I have some extremely naive first-time GPU-user type questions. My excuse for asking them here is that as the ATI SETI aps move closer to mass-market distribution, you may get more people like me--who have never done CUDA work and don't know some of the "obvious" things. I've read the referenced posting at the Lunatics site, and am only asking what I believe to be additional clarification or additional coverage. Links or inline answers equally welcome.

1. In setting my BOINC Computing preferences for the location (some call it venue) of my ATI host, does my ATI card count as a processor for the number of processors limit (i.e. if 4-core CPU, should it be set to 5?). And on the % of processors limit, does it count in the numerator and not denominator--thus in same case need 125% minimum?

2. Can additional insight into the behavior of, or wisdom into good values for the following parameters set in ap_info be shared?

a. <avg_ncpus>0.01</avg_ncpus>

b. <max_ncpus>0.01</max_ncpus>

c. <flops>15987654321</flops>

3. Are we naive users who have not run GPU before and may set a wildly wrong flops value in danger of massive over-downloading initially? Any suggested precautions for avoiding that? (such as setting an extremely small sum for the internet connection interval plus additional days work of e.g. 0.001).

4. Are we naive users who run multiple projects in danger of greatly unbalancing SETI vs. other project workload (perhaps by setting inappropriate flops number) initially? Suggested ameliorative actions?

5. Even after use has gone on for a while, may the host's Task Duration Correction Factor fluctuate strongly with the happenstance of available Astropulse handled by GPU vs. standard CPU-borne SETI work, and thus have alternation of overfetch and underfetch? Suggested ameliorative actions?

6. I believe that if I first ran my queue to zero, then did a correct install for one of these new ATI/Astropulse aps, but removed the other ap sections in my ap_info, I would receive only Astropulse downloads from SETI. Is that right, and is there any good reason not to? {edit: in the event I did run down my queue to zero, and currently have an ATI-only ap_info. When work becomes available again I can comment on how that worked).

7. I never game, and my new host has a fanless HD4550 card. I have decent case cooling support for it (an 800 rpm 120mm fan in a side port right over it, and no other add-on cards with power dissipation above the nuisance level). Am I in danger of greatly exceeding the previous temperature of my GPU? Any practical suggestions of monitoring tools, throttling methods, and practical temperatures of concern. I have and plan to watch GPU-Z. It reports 60C with 0% reported workload now, though the actual metal cage over the fins is only warm, not painfully hot.

These are sincere questions, not hostile attacks. Right now have suspended Einstein and suspended SETI work fetch, and hope to have my SETI work queue down to zero in time to do a trial install this evening (U.S. MDT). Any questions answered will be a plus for me--and possibly some others.
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7. I never game, and my new host has a fanless HD4550 card. I have decent case cooling support for it (an 800 rpm 120mm fan in a side port right over it, and no other add-on cards with power dissipation above the nuisance level). Am I in danger of greatly exceeding the previous temperature of my GPU? Any practical suggestions of monitoring tools, throttling methods, and practical temperatures of concern. I have and plan to watch GPU-Z. It reports 60C with 0% reported workload now, though the actual metal cage over the fins is only warm, not painfully hot.

I have some extremely naive first-time GPU-user type questions.

7. I never game, and my new host has a fanless HD4550 card. I have decent case cooling support for it (an 800 rpm 120mm fan in a side port right over it, and no other add-on cards with power dissipation above the nuisance level). Am I in danger of greatly exceeding the previous temperature of my GPU? Any practical suggestions of monitoring tools, throttling methods, and practical temperatures of concern. I have and plan to watch GPU-Z. It reports 60C with 0% reported workload now, though the actual metal cage over the fins is only warm, not painfully hot.

These are sincere questions, not hostile attacks. Right now have suspended Einstein and suspended SETI work fetch, and hope to have my SETI work queue down to zero in time to do a trial install this evening (U.S. MDT). Any questions answered will be a plus for me--and possibly some others.

Not bad.

First one ran in approx. 5.5 hours.
The second one in 2 seconds, but that looks to be a task error:

Error in ap_remove_radar.cpp: generate_envelope: num_ffts_performed < 100. Blanking too much RFI?

Max GPU temperature, 51C.

CAL ATI Radeon HD 4700/4800 (RV740/RV770) (1024MB) driver: 1.4.696

For your system, what does the same monitoring method give for GPU temperature at idle?

The SETI page for your hosts lists the graphics processor as:

CAL ATI Radeon HD 4700/4800 (RV740/RV770) (1024MB) driver: 1.4.696

What is the particular product you have?

OK, I have to ask. I've seen this behaviour on 2 OpenCL APs now.
It starts up, taking about 78MB physical memory, runs for about 2 minutes then stops using the GPU. The next 10 to 20 minutes it's using the CPU only, memory usage slowly increasing to ~230 - ~280MB. Then the GPU kicks back in and physical memory is slowly bleeding back to 78MB.

What's happening in the 10-20 minutes and to 230 - 280MB increase? Is it making an array of (simulated) (possible) work to do, to then start on the best one?
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Jord

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