CPU vs GPU tasks and credits

Joshua
Joshua
Joined: 25 Jul 18
Posts: 38
Credit: 16,710,068
RAC: 33
Topic 215994

Hi Everyone,

I started E@H about a week ago and had some beginner questions. If someone can help answer them or point me towards a thread that deals with the same topic that would be awesome!

I have a relatively low-powered PC compared to many others with a i5-4590 processor and a single AMD RX 560 GPU. It takes each of my CPU tasks called "Continuous Gravitational Wave Search O2 All-sky" between 7-9 hours to complete. BOINC runs 4 of these tasks at a time, one on each core. My GPU does the "Gama-ray pulsar binary search #1" task in about 30 minutes. 

Given that the CPU tasks take considerably longer, I was surprised to learn that they each award 1000 credits while the GPU tasks each award 3465 credits. 

 

Here are my questions:

1. Are the CPU tasks run on each core really a lot less work overall than the GPU tasks?

2. If so, then my CPU just works much, much slower than my low-ed RX 560 GPU on tasks?

3. I think I know what the "Continuous Gravitational Wave Search O2 All-sky" task does by reading the SCIENCE info on this website. What does the "Gama-ray pulsar binary search #1" task do? I'm interested in knowing what the computer is really doing.

 

Thank you!

 

 

Gary Roberts
Gary Roberts
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Joined: 9 Feb 05
Posts: 4,794
Credit: 27,211,650,994
RAC: 34,876,444

Hi Joshua, Welcome to the

Hi Joshua,
Welcome to the Einstein project.!

Joshua_48 wrote:
... point me towards a thread that deals with the same topic that would be awesome!

You could try reading this thread which covers similar questions.  A CPU core is a single processing unit..  A GPU core may contain thousands of 'stream processors'.  If a task can be attacked in a massively parallel fashion, there will be a very large throughput gain even though the stream processor is a very simple beast compared to a CPU core.

Joshua_48 wrote:
I have a relatively low-powered PC compared to many others with a i5-4590 processor and a single AMD RX 560 GPU. It takes each of my CPU tasks called "Continuous Gravitational Wave Search O2 All-sky" between 7-9 hours to complete. BOINC runs 4 of these tasks at a time, one on each core. My GPU does the "Gama-ray pulsar binary search #1" task in about 30 minutes.

The i5-4590 is listed as 4 cores/4 threads (no HT).  It's quite a decent CPU.  If you are able to run 4 concurrent CPU tasks and a single GPU task, you must have altered (through an app_config.xml file, perhaps?) the default which would 'reserve' a full CPU core for GPU support duties.  The default would only allow 3 CPU tasks to run concurrently with a GPU task.  I have some similar hosts with Haswell era Pentiun dual core CPUs (G3260) and RX 560 GPUs.  The CPU performance is largely irrelevant as the GPU is the real workhorse.  Mine completes two concurrent GPU tasks about every 38-39 mins compared to about 23-24 mins each if I were processing these tasks consecutively.  Your figure of 30 mins is surprisingly good if you really are running 4 concurrent CPU tasks.  There is usually a bigger 'penalty' for fully loading all CPU cores.

Try reading the other thread I linked and come back here and ask again if you have any follow-up queries.

Joshua_48 wrote:
... What does the "Gama-ray pulsar binary search #1" task do? I'm interested in knowing what the computer is really doing.

The gamma-ray pulsar search is looking for unknown pulsars that emit gamma rays rather than radio waves.  Previously, there were searches for radio pulsars using data from the Arecibo and Parkes radio telescopes.  There were quite a large number of discoveries from this data.  There is background information about this here and information about discoveries here.

The Fermi satellite has a gamma ray detector on board which provides the data for all FGRP searches, both CPU and GPU.  This search is ongoing.  There is a good description here.

 

Cheers,
Gary.

Joshua
Joshua
Joined: 25 Jul 18
Posts: 38
Credit: 16,710,068
RAC: 33

Thanks Gary! I'll read up on

Thanks Gary! I'll read up on those threads.

BOINC automatically started me with 4 cpu threads. I haven't changed any settings. I also ran SETI and MILKYWAY for one day each before starting here. Maybe one of those affected the settings.

Would you recommend going down to 3 cpu cores and up to 2 tasks on the GPU? If so, please let me know what to do.

Gary Roberts
Gary Roberts
Moderator
Joined: 9 Feb 05
Posts: 4,794
Credit: 27,211,650,994
RAC: 34,876,444

Until you get used to how

Until you get used to how things work, you should hasten slowly :-).  If Einstein is the only project you have that is active now, what have you done with the others?  I presume you may have set NNT for them or perhaps even disabled or removed them completely.  What is your ultimate aim?

If we just talk about Einstein for the moment, there are three active searches that are open to you, two for CPU cores and one for your GPU.  If you set a work cache of 0.5 days for starters and leave most other things at default values, your BOINC client will ask for work as needed and the server will supply for all three.  It's many years since I knew what the default settings were, but I think you will probably be automatically participating in all three searches.  Just check through all the project and computing preferences on the website to get an overview with the things you can play with.  If you decide to change anything you need to go to the bottom of the page you are on and click the 'save' option.

With default settings, if your GPU is crunching a task, one CPU core will automatically be 'reserved' for GPU 'support' duties.  You don't need to do anything about that.  Can you please open BOINC Manager Advanced View and examine the tasks tab to see what tasks you have and exactly what is crunching.  Put in your next response the type of tasks you have and how many of each are crunching concurrently.  If nothing has been modified, it should be 3 CPU tasks and one GPU task.  You may have been crunching 4 CPU tasks initially if you didn't have any GPU tasks.  As soon as a GPU task starts to crunch, one of the 4 CPU tasks would pause and only three would be left running.  The paused task would resume when a running task was completed.

 

Cheers,
Gary.

Joshua
Joshua
Joined: 25 Jul 18
Posts: 38
Credit: 16,710,068
RAC: 33

First, thank you for all of

First, thank you for all of your help!

You're correct, my PC has 4 CPU tasks OR 3 CPU + 1 GPU task at a time. I have BOINC set to disable the GPU task when the PC is in use so I usually see that 4 CPU tasks are working and the GPU task is waiting while I am using this computer.

When I changed the setting so that the GPU still gets used when I am on the PC, then one of the CPU tasks paused and I had only 3 CPU tasks.

I removed the other 2 projects from BOINC and plan only to participate in Einstein at Home.

Gary Roberts
Gary Roberts
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Joined: 9 Feb 05
Posts: 4,794
Credit: 27,211,650,994
RAC: 34,876,444

OK, thanks for that.  It's

OK, thanks for that.  It's now clear to me why you will see 4 CPU tasks running when you are using your computer.

My experience is that for normal 'office' type duties, letting GPU tasks crunch continuously doesn't have a noticeable impact on the 'usability' of the machine.  This is even so when running two concurrent GPU tasks.  If you're interested in maximising your output, it's worth experimenting for a bit to see if crunching continuously with the GPU has any adverse effect for you.

Another thing to decide about is the effect that crunching will have on electricity costs and hardware life.  For many, electricity cost is a big deal.  Crunching will increase your use of power considerably and this will show in your electricity bill.  Because GPU crunching produces more work output per kW consumed, some people tend to disable CPU crunching and just use the GPU.

Hardware life is sensitive to excessive heat so you should keep a close eye on your cooling system.  Monitoring temperatures and investigating sudden changes are important things to do.  CPU fans, PSU fans and case fans can all run out of lubricant and create heat issues quite quickly.   With fans working harder, noise may be an issue and the tendency for dust and fluff to clog up fins on heat sinks, you will need to pay some attention to these potential problems.  As long as you maintain proper cooling, the hardware can run for many years.

So, if you're comfortable with running costs and dealing with excess heat, and are still interested in getting more out of your GPU, let me know and I'll give you options for how best to do that.

 

Cheers,
Gary.

DanNeely
DanNeely
Joined: 4 Sep 05
Posts: 1,273
Credit: 1,279,659,135
RAC: 1,091,660

Joshua_48 wrote:Thanks Gary!

Joshua_48 wrote:

Thanks Gary! I'll read up on those threads.

BOINC automatically started me with 4 cpu threads. I haven't changed any settings. I also ran SETI and MILKYWAY for one day each before starting here. Maybe one of those affected the settings.

Would you recommend going down to 3 cpu cores and up to 2 tasks on the GPU? If so, please let me know what to do.

 

You haven't specified what OS you're using and have your computers set to hidden.  There's a bug somewhere in the software stack for AMD 4xx/5xx GPUs (not sure if anyone knows if it's the driver, OS, or science app) that causes compute speed to slow down massively if you try running 2 tasks at a time in Windows.  It doesn't affect NVidia GPUs, older AMD GPUs, or (I think) AMD 4xx/5xx GPUs running Linux instead of windows.

Joshua
Joshua
Joined: 25 Jul 18
Posts: 38
Credit: 16,710,068
RAC: 33

DanNeely wrote: You haven't

DanNeely wrote:

You haven't specified what OS you're using and have your computers set to hidden.  There's a bug somewhere in the software stack for AMD 4xx/5xx GPUs (not sure if anyone knows if it's the driver, OS, or science app) that causes compute speed to slow down massively if you try running 2 tasks at a time in Windows.  It doesn't affect NVidia GPUs, older AMD GPUs, or (I think) AMD 4xx/5xx GPUs running Linux instead of windows.

Hi, I have windows 10, and I went to privacy settings to allow my pc to be seen. I'm not sure how that got switched off. I don't remember ever setting it.

Thanks!

Holmis
Joined: 4 Jan 05
Posts: 969
Credit: 623,443,298
RAC: 894,306

Joshua_48 skrev:Hi, I have

Joshua_48 wrote:

Hi, I have windows 10, and I went to privacy settings to allow my pc to be seen. I'm not sure how that got switched off. I don't remember ever setting it.

Thanks!

I believe that since the EU introduced GDPR in May the default setting for new accounts is to hide computers on the web site.

Shawn Kwang
Shawn Kwang
Moderator
Administrator
Joined: 3 Nov 15
Posts: 270
Credit: 689,166
RAC: 409

Holmis wrote: I believe that

Holmis wrote:

I believe that since the EU introduced GDPR in May the default setting for new accounts is to hide computers on the web site.

Holmis is correct, the new default is to hide your computers. If you haven't already done so, you may change this setting in Account -> Preferences -> Privacy, look for "Should Einstein@Home show your computers on its web site?". Enable by clicking 'Yes'.

Einstein@Home Project

raghuram
raghuram
Joined: 8 Jul 18
Posts: 6
Credit: 3,205,504
RAC: 5,336

Hi, I'm new here. I have

Hi, I'm new here.

I have Dell Inspiron i7-5500 cpu @2.4ghz cpu with 16gb RAM, pretty basic.

I don't want to spend tons of money, want to know how can I increase the throughput.

Is it simple to get 1 or 2 GPUs and hook it up or how best to upgrade my current hardware.

 

Thanks,

Raghu

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