mfaktc: a CUDA program for Mersenne prefactoring

[Honza]

Same error on GTX 2080 as Titan V, as shold be expected.

d:\TeMp\MFakt>mfaktc-win-64.exe -st
mfaktc v0.21 (64bit built)

Compiletime options
  THREADS_PER_BLOCK         256
  SIEVE_SIZE_LIMIT          32kiB
  SIEVE_SIZE                193154bits
  SIEVE_SPLIT               250
  MORE_CLASSES              enabled

Runtime options
  SievePrimes               25000
  SievePrimesAdjust         1
  SievePrimesMin            5000
  SievePrimesMax            100000
  NumStreams                3
  CPUStreams                3
  GridSize                  3
  GPU Sieving               enabled
  GPUSievePrimes            82486
  GPUSieveSize              64Mi bits
  GPUSieveProcessSize       16Ki bits
  Checkpoints               enabled
  CheckpointDelay           30s
  WorkFileAddDelay          600s
  Stages                    enabled
  StopAfterFactor           bitlevel
  PrintMode                 full
  V5UserID                  (none)
  ComputerID                (none)
  AllowSleep                no
  TimeStampInResults        no

CUDA version info
  binary compiled for CUDA  8.0
  CUDA runtime version      8.0
  CUDA driver version       10.0

CUDA device info
  name                      GeForce RTX 2080
  compute capability        7.5
  max threads per block     1024
  max shared memory per MP  65536 byte
  number of multiprocessors 46
  clock rate (CUDA cores)   1860MHz
  memory clock rate:        7000MHz
  memory bus width:         256 bit

Automatic parameters
  threads per grid          753664
  GPUSievePrimes (adjusted) 82486
  GPUsieve minimum exponent 1055144

########## testcase 1/2867 ##########
Starting trial factoring M50804297 from 2^67 to 2^68 (0.59 GHz-days)
Using GPU kernel "75bit_mul32_gs"
Date    Time | class   Pct |   time     ETA | GHz-d/day    Sieve     Wait
Sep 25 17:50 | 3387   0.1% |  0.025    n.a. |      n.a.    82485    n.a.%
ERROR: cudaGetLastError() returned 8: invalid device function

[storm5510]

Originally Posted by Honza

Same error on GTX 2080 as Titan V, as shold be expected.

ERROR: cudaGetLastError() returned 8: invalid device function

I had this same exact error on two other cards, GTX 480 and GTX 750Ti, when I tried to overclock them. I have a feeling this has something to do with mfaktc itself. It can only handle so much speed.

Q.: Have you tried running CUDALucas or CUDAPm1?

[kladner]

Originally Posted by storm5510

I had this same exact error on two other cards, GTX 480 and GTX 750Ti, when I tried to overclock them. I have a feeling this has something to do with mfaktc itself. It can only handle so much speed.

Q.: Have you tried running CUDALucas or CUDAPm1?

How high did you get with the GTX480?

[Honza]

Originally Posted by storm5510

Q.: Have you tried running CUDALucas or CUDAPm1?

Nope.
I would need a link to Windows binary...

[James Heinrich]

Your one-stop-shop for mersenne binaries/source: https://download.mersenne.ca/

No guarantees though that the latest mirrored versions support the RTX 2080.

[kriesel]

Originally Posted by Honza

Nope.
I would need a link to Windows binary...

See the last page in "Available software" thread ("sticky", top of the list in GPU Computing)
or go directly to https://www.mersenneforum.org/showth...291#post488291

[ATH]

For 2080 he needs a binary with CUDA 9.2.0.88 or newer, and no one has compiled a Windows binary.

I tried to compile for my old Titan Black but cannot get it to compile.

[storm5510]

Originally Posted by kladner

How high did you get with the GTX480?

I didn't get very far. It was a bit odd. GPU-Z reported its base frequency as 700 MHz. Afterburner said 1400 MHz. At its base, mfaktc would run 330 GHz-d/day. The most I ever got was 390 GHz-d/day. Beyond that, error. I had to reboot to get it to reset because it would drop way down. Something like 325 MHz.

[kriesel]

Originally Posted by ATH

For 2080 he needs a binary with CUDA 9.2.0.88 or newer, and no one has compiled a Windows binary.

I tried to compile for my old Titan Black but cannot get it to compile.

Right, thanks for the reminder on CUDA level. If anyone gets a version compiled above CUDA 8.0, please share and notify James Heinrich and me, so that the mirror and the available software list get updated.

[nofaith628]

As you may have read in my previous call for help, my switch from GTX 1080TI to a Titan V has resulted in errors.

Previous attempts to assuage this issue:

ERROR: cudaGetLastError() returned 8: invalid device function

have failed, regardless of attempts to reinstall, clean install and uninstall display driver and CUDA, as well as tweaking settings in mfaktc.ini.

Without any prerequisite knowledge on computer programming and compilation. I have managed to compile a non-optimized version of mfaktc 10.0, it currently works with the Titan V. The GHz-days output is not good, but it works.

As for the rest, I have discussed with Oilver (TheJudger) that he may release an optimized mfaktc for the Turing architecture in the near future, there are no plans to optimize the code specifically for Volta Architecture as it has a very high entry price.

[Honza]

I guess old cudart32_80.dll and cudart64_80.dll needs to be updated with cudart32_100.dll and cudart64_100.dll