Posts by JohnMD

1) Message boards : Number crunching : Why isn't the project GPU-only by default? (Message 1401)
Posted 13 May 2020 by Profile JohnMD
I am new here, so please be kind if I am totally off on this, and I apologize if I am.

That said, I don't quite understand why the project is sending CPU-only tasks when it seems to take more than 100x longer.

Why hasn't the project become GPU-only, or at least GPU-only by default?

Especially with the pentathlon coming up, you would think we would want to have the most efficient way of completing tasks being the default?



Uncheck the CPU box in Amicable preferences if you don't want to use your CPU.
The project just wants to get as many WU's done as possible !
2) Message boards : Number crunching : Um, Got a Couple of Whoppers? (Message 1383)
Posted 19 Apr 2020 by Profile JohnMD
I returned the following task yesterday it ran for just over 52 minutes. It took the other person over 4 hours on an AMD card. I am just wondering why this took such a long time to run and whether or not it was related to the tasks quite some time ago that got granted more credit? Unfortunately I am unable to find that thread

Don't you know that -
1) Some people don't have as good equipment as you.
2) Some 'wingmen's tasks terminate without a result, and have to be resent to a another cruncher.
3) Some cruncher-wingmen accumulate a task queue with up to 10 days' work - you need to wait those days before your work can be confirmed.
We are all volunteers - some more voluntary than others ! Have patience - your efforts are not in vain.
3) Message boards : Number crunching : Um, Got a Couple of Whoppers? (Message 1368)
Posted 25 Mar 2020 by Profile JohnMD
A reboot of my laptop seems to work.
I will monitor for the next few days

Note that the start phase of these WU's requires 3GB RAM - you'd be hard pushed to start 2 at a time, and certainly not 3.
4) Message boards : News : The search up to 10^21 (Message 1307)
Posted 16 Nov 2019 by Profile JohnMD
Is there a minimum requirement for GPU RAM ?
5) Message boards : Bug tracker : Constant Computation errors (Message 1283)
Posted 31 Oct 2019 by Profile JohnMD
In my experience, IBM's OS2 was the ONLY PC system that could efficiently handle virtual storage.
Forget upping swap-file. Buy some more RAM !
6) Message boards : News : The search up to 10^21 (Message 1269)
Posted 28 Oct 2019 by Profile JohnMD
Note that system memory requirements are higher now because all prime numbers < 1011 need to be stored in memory for the search.

Resources per CPU WU are doubled - both memory and CPU-cycles. Shouldn't credit follow suit ?
Can't the allocated cores share a single copy of primes in memory ?
7) Message boards : News : The search up to 10^20 (Message 1229)
Posted 20 Oct 2019 by Profile JohnMD
What would the RAM requirement be for the search to 10^21? I would guess that it wouldn't quite be a 10x jump to 15GB, but it could still be quite substantial.

The memory required is O(sqrt(N)), so it will not be a 10x jump:
CPU version would require ~1400 MB of memory.
GPU version would require ~3700 MB of GPU memory.

Great! Thank you for the quick reply! That is better than I thought. 3700MB for GPU would still leave a large portion of GPUs capable of participating and only 1400MB for CPU is quite low so I doubt anyone would be left out of the search up to 10^21 if it occurs.

1400MB seems to be about right for 2 cpus.
Up to 1000MB is released and re-allocated every minute.
While 'used memory' is reasonably stable, allocated memory gradually increases.
This might be Windows' fault - but it might also be forgetfulness by Amicable.
Answers please - on a postcard - to - boinc'ers with small machines !
8) Message boards : Number crunching : Computation error (Message 1102)
Posted 13 Mar 2019 by Profile JohnMD
I get the same "-58" in 2 situations with Nvidia 930M (I also have Intel 520 for display)
1. When I close BOINC and restart. The GPU app CAN'T restart, even though it has created a checkpoint file.
2. When I switch to another user, the GPU app gets suspended. When I switch back it CAN'T resume, even though suspended tasks are 'kept in storage'.
Sounds to me like something's been forgotten and the program not properly tested.
9) Message boards : Bug tracker : deadline too short (Message 1051)
Posted 5 Jan 2019 by Profile JohnMD
Under my "project preferences" I have said -
Max # CPUs 2
The result shows that this is not respected
Please correct your system
10) Message boards : Bug tracker : The project send tasks to a video card with only 1G memory (Message 797)
Posted 22 Apr 2018 by Profile JohnMD
Most of my NVIDIA graphics cards are larger than 1G, and it seems that the device has not been able to get the task changed just a few days ago.

Your hardware is hidden, so it is not possible to help you.
11) Message boards : Number crunching : GPU version requirements for the search up to 10^20 (Message 792)
Posted 18 Apr 2018 by Profile JohnMD
Current GPU version's requirements: any AMD (HD 5xxx or newer) or NVIDIA (GTX 4xx or newer) GPU with OpenCL support and at least 2 GB of video memory

If you run an AMD card on Windows, make sure you use driver version 14.12 or newer, otherwise it may fail at startup because of OpenCL code compilation error.

Now that WU's allocate less than 900MB, is it possible to relax the GPU memory requirement to 1GB ?

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