Did anybody of you tested if with higher priority was still beneficial to assign a full cpu core to the application (SWAN_SYNC)?

Are there any collateral effects in increasing the priority to high-priority (like slow response of the desktop)?

thanks,
gdf

Did anybody of you tested if with higher priority was still beneficial to assign a full cpu core to the application (SWAN_SYNC)?

I tried increasing ACEMD's priority before I knew about the SWAN_SYNC environmental setting. Boosting ACEMD's priority in itself increased minimally the GPU usage and decreased the running time. (It was a previous version of ACEMD) Then, I searched the forum for performance increasing tips, and I learned about the SWAN_SYNC setting. I haven't turned it off since then. Using SWAN_SYNC=1 and increasing ACEMD's priority at the same time helps ACEMD to maintain the GPU usage, regardless of other tasks or applications I'm using. If I don't boost ACEMD's priority, the GPU usage drops when I start other applications (and it jumps back to normal very soon).

Are there any collateral effects in increasing the priority to high-priority (like slow response of the desktop)?

I've increased acemd's priority to "above normal". Everything seems to be fine, except watching movies (especially HD movies).

Are there any collateral effects in increasing the priority to high-priority (like slow response of the desktop)?

If I set ACEMD to normal, desktop had time to time slow response - up to 2s, and PT i had to set to high priority. If I set ACEMD to high priority, desktop was sluggish. (GTX560Ti factory OC to 900MHz, XP 64bit, Swan_Sync=0 set, one CPU core free out of Boinc, GIANNI_DHFR task - GPU utilization 99%).

Did anybody of you tested if with higher priority was still beneficial to assign a full cpu core to the application (SWAN_SYNC)?

Are there any collateral effects in increasing the priority to high-priority (like slow response of the desktop)?

thanks,
gdf

I did some experiments with the app_info.
I kept one cpu free with the setting
<avg_ncpus>1</avg_ncpus>
<max_ncpus>1</max_ncpus>
This had the best effect.

Setting the priority to 'above normal' helped when the original setting of 0.24 was applied (~2% faster) but had nearly no effect with one cpu for the app.
When GPU-usage is below 80% the highest increase of speed can be achieved when running two apps together with a setting of <count>0.5</count> and the <avg_ncpus> also to 0.5
This setting brought an overall increase of more than 10%, but is senseless for wu's with gpu-usage of 90% or better.
I would not prefer the higher priority because I use my system for daily work, where I would otherwise see a performance decrease.
Edit: I forgot: win7x64 E8400 6GB 6.12.13

When I increased the priority of the GPUGrid task, my computer's regular performance wasn't affected. I could still do day-to-day things such as going online, watching YouTube, and playing music with no performance hits. However, when I checked how much CPU time was being used by GPUGrid, it's at 0%! To make matters worse, it seemed like it wasn't doing any work at all! This was when I set the number of processors to be used to 100%. Rosetta@Home then proceeds to use all four cores. What's interesting, though, is that even though Rosetta@Home has the lowest priority compared to GPUGrid, it still seems to hog nearly 100% of the CPU time in the fourth core.

Another thing to note is that I removed SWAN_SYNC, as it doesn't appear to do anything. There is no mention of SWAN synchronization in any of the stderr outputs I can see in my completed tasks. For the record, I'm using Linux Mint 10 (which is based on Ubuntu 10.10) with a Core i5-750 processor and a GTX 570 GPU.

Could you look into this GDF? I really want to crunch for both Rosetta@Home and GPUGrid at the same time.

Kirby54925, set your CPU usage to 75%. You have a GTX570, it needs to be able to use some of the CPU. If you let Rosetta hog all the CPU cores you will knobble the GTX570 performance. I would expect the difference between CPU Time and RunTime to also drop somewhat for your Rosetta tasks, so you would not quite be losing a full CPU core anyway.

GDF, I pushed the Priority to High on all four GT240's in the one system when not using swan_sync. It only increased GPU Utilizaion on one GPU by about 4% - none of the others changed. No problems with the system (also running CPU tasks at the time). I have not tried it when swan_sync is being used, but I see little point. Tasks were running between 65% and 90% utilization. The increase from using swan_sync now appears to be less than 10% for GT240’s running the 6.12app on Vista x64, while running CPU tasks.

So, we can focus on SWAN_SYNC alone and let people use it via project preferences?

gdf

A preference for swan_sync would be useful, especially if you could do it for Linux.

It is already possible to reduce the number of CPU cores to use (for CPU projects) from Computing preferences (and Boinc Manager):
On multiprocessors, use at most - 100.0 % of the processors.

ok

Swan_Sync XOR one free core out of Boinc makes the same for GPU load (Win XP). By my point of view is more useful to use Swan_Sync than free core for extraordinary cases - e.g. GPUGRID is down, GPU is running backup project with low CPU utilization (i have set PG) and machine is not baby-sited. When I leave machine for longer than buffer of GPUGRID tasks has got, I switch Boinc from 75% CPU cores to 100% CPU cores. So I switch in the evening 75% to 100% and in the morning from 100% to 75%. Why? Swan_Sync AND one free core makes GPU load from +2% to 5% higher depending on tasks except GIANNI_DHFR as that kind of task makes GPU load 96% - 98% using only one of these features.

In the future most of the tasks will reach 96-98% load.

gdf

another odd thing is that if i overclock from 650mhz to 850mhz the gtx 460 768mb when the game has 60%gpu the fps does not increase.

Sounds like you're running into a cpu or other limit.

MrS

---

Scanning for our furry friends since Jan 2002

Performance changes with different tasks, but this should generally improve soon*.

All CC2.1 cards, including the GTX460, have a somewhat incomplete ability at GPUGrid due to shader access problems, mostly down to the ACEMD application, I think. This is why I advise people to get CC2.0 cards if possible. Perhaps the remaining third of the shaders will be usable in a future ACEMD edition. It would be a very nice boost to the project.

It’s down to the project managers to say what is urgent for GPUGrid (an ATI app, new faster routines*, long tasks, server or website maintenance, support, presentations, publications...), and they can’t do much in some areas (tools and drivers) other than wait. Unfortunately this is the situation with CC2.1 cards.

All we crunchers can do is report problems, make suggestions and optimize our systems as best we can; using swan_sync=0, freeing up a CPU core for every GPU, configuring your preferences, reporting tasks immediately and using a fast operating system - due to the WDM overhead Vista and Win7 are slower than XP and Linux, though this may not be apparent from looking at GPU Utilization, but rather through task performance.


Good luck,

What's the best CC2.0 card you can suggest that uses no more power than a GT240? It looks like I'll be getting another computer soon, but with a rather strong limit on the amount of power it can use.

There is none and this is a problem for the project.
The GT440 would perform no better than a GT240. Stay away from the GT430 and below (if you can); as far as I know these are cc2.1. Ditto for the GTS450, GTX460 and GTX560.
There is a very big gap between the GT240 and the GTX465 (the lowest powered CC2.0 Feri). The only CC2.0 cards are the GTX 465, 470, 570 and 580. These are all 200W+

How long do you expect the CC2.1 problem to last, or do you expect it to be permanent even for new versions of the application?

I am fairly sure the CC2.1 problem is here for the immediate to midterm future (0-6 months); I don’t know of any mid-range CC2.0 cards being developed and software changes take a long time and may never resolve the situation. Beyond 6 months there are some possible changes (program/kernel or app) that might improve CC2.1 performance but there is no guarantee. It would be wrong to get a GPU thinking that improvement is just around the corner.

Looks like the long tasks have finally arrived!

Yes they have, but so far all my completed ones are 'pending validation'. However on the server status page, it shows none are waiting for validation?

It should have been fixed now by Toni.

gdf

Sweet! Thanks for the fix!

As for you Stoneageman, how's your electric bill? It must be really high to be running all those computers! (Not to mention that getting all those GTX 580s costs a pretty penny...)

EDIT: GDF, if I select both the ACEMD2 and ACEMDLONG tasks in my GPUGrid preferences, does the ACEMDLONG task have a higher priority?