Running multiple tasks concurrently per GPU - How to revert to just one task.

mikey
mikey
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KLiK wrote: Keith Myers

KLiK wrote:

Keith Myers wrote:

You need to try to stagger the task startups on the gpu so that they all don't converge at the 49% and 99% cpu offload points when running gpu task multiples.

Just suspend a task that starts anew on the gpu until the previous one had made progress halfway to one of its cpu compute intervals, then un-suspend the task.

Thank you.

Immediate result can be seen:

 

It sure looks like both tasks have started and running in sync instead of opposite to each other

Ian&Steve C.
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mikey wrote: It sure looks

mikey wrote:

It sure looks like both tasks have started and running in sync instead of opposite to each other



you're focusing on the wrong part of the graph. the beginning is with the tasks not staggered, but the end shows the second task start right when the first task ends, leading to near constant GPU utilization. you can see a slight dip in temp, then it comes right back up instead of falling down like the previous two cycles.

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mikey
mikey
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Ian&Steve C. wrote: mikey

Ian&Steve C. wrote:

mikey wrote:

It sure looks like both tasks have started and running in sync instead of opposite to each other



you're focusing on the wrong part of the graph. the beginning is with the tasks not staggered, but the end shows the second task start right when the first task ends, leading to near constant GPU utilization. you can see a slight dip in temp, then it comes right back up instead of falling down like the previous two cycles. 

okay thanks

KLiK
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mikey wrote:Ian&Steve C.

mikey wrote:

Ian&Steve C. wrote:

mikey wrote:

It sure looks like both tasks have started and running in sync instead of opposite to each other



you're focusing on the wrong part of the graph. the beginning is with the tasks not staggered, but the end shows the second task start right when the first task ends, leading to near constant GPU utilization. you can see a slight dip in temp, then it comes right back up instead of falling down like the previous two cycles. 

okay thanks

Its like @mikey said. 

But also, there are 2 cards in the system. So both cards work, that is why there are 2 graphs!

(Though my M5000 & P4 was read with only single temp., so I changed from M5000 to P2000...waiting for Eintein@home tasks to start again, to show the real results.)

Main thing is: previous dips were after around 18~20min of GPU & lasted for about ~15min with CPU time. If I run 2x per GPU, then the 2nd task can almost be over by the time 1st one finished it CPU calc. ????

KLiK
KLiK
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Keith Myers wrote: Yes, same

Keith Myers wrote:

Yes, same principle. But in my experience so far with MeerKAT tasks, they don't respond as well to 2X as the optimized app for GR#1.  You won't see as much benefit . . . .  if any.

They also use  more VRAM.  2X may be cutting it close with 6GB.

Are you sure about that? This is MeerKAT, with only 22~25% load & not much memory used.

Did anybody use 2x WU on stronger cards, like Teslas - which can crunch more data? What are the experiences? 

GWGeorge007
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KLiK wrote: Keith Myers

KLiK wrote:

Keith Myers wrote:

Yes, same principle. But in my experience so far with MeerKAT tasks, they don't respond as well to 2X as the optimized app for GR#1.  You won't see as much benefit . . . .  if any.

They also use  more VRAM.  2X may be cutting it close with 6GB.

Are you sure about that? This is MeerKAT, with only 22~25% load & not much memory used.

Did anybody use 2x WU on stronger cards, like Teslas - which can crunch more data? What are the experiences? 

Your image doesn't show much of a load from a Tesla card, and your two Tesla K20Xm's have less than 6GB of VRAM in Windows 10 running an Intel i7-5820K CPU.  It may matter what your PC & BOINC specs are set to.

George

Proud member of the Old Farts Association

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