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2015-01-02, 22:49   #1288
kracker

"Mr. Meeseeks"
Jan 2012
California, USA

32×241 Posts

Quote:
 Originally Posted by Bdot Hmm. Weird. Now it is at 424 GHz ... I'll monitor it. Looks like something ran in the background ...
Wow... this is weird. I had reverted to a older driver(14.3) and it still gave me errors when I ran -st2 just now. Going to do a little investigating...

 2015-01-05, 00:55 #1289 kracker     "Mr. Meeseeks" Jan 2012 California, USA 216910 Posts Hmm, I don't know what's up. -st2 with GCN2 works, and mfakto 0.14 works too...
2015-01-12, 15:57   #1290
Bdot

Nov 2010
Germany

3·199 Posts

Quote:
 Originally Posted by kracker Hmm, I don't know what's up. -st2 with GCN2 works, and mfakto 0.14 works too...
Now my GPU slowed down again. Seems to be the GPU memory access that almost blocks it. I still blame the driver.

Anyway, I now reproduced the error (I just needed to set GPUType=GCN ). I did not yet check why 0.14 does not show this, but the reason is that I missed a part in my error estimation. The 15-82, 15-83 and 15-88 bit kernels can have a higher error than I expected - so they cannot reliably do the last bitlevel they're enabled for. In other words, if you've done TF tests beyond 81 bits using a GCN GPU, there's a small chance of missed factors. Not sure how small, but most of the selftests do succeed. I'll try to find out about 0.14 tonight.

To fix it, I can either reduce the kernels' bitlevel, or add code to reduce the error, which will slow it down a bit. I have not yet decided.

 2015-01-12, 23:22 #1291 Bdot     Nov 2010 Germany 3×199 Posts Mfakto 0.14 bug warning for 81-82, 82-83 and 87-88 bit tests mfakto version 0.14 did not have these errors because the failing tests were part of another 2300 tests that I only added for 0.15. I built a version of 0.14 with just these tests added, and they are failing too. This means that these tests were unreliable: run 81-82, 82-83 or 87-88 bits on any GCN GPU (other GPUs would select a different kernel) out of 262 test cases in these 3 ranges, 9 are failing (~3.5%). Due to the small number of tests, the error percentage is rather inexact. Please do not use mfakto 0.14 for tests beyond 80 bits on GCN. I will reduce the bitlevels of these kernels to a safe level for 0.15 and add another kernel that has the additional code to safely run to 88 bits. I'm sorry.
 2015-01-13, 05:45 #1292 LaurV Romulan Interpreter     Jun 2011 Thailand 25·5·59 Posts Very good job Bdot! (it does not affect me, due to the speed penalty at higher bitlevels, I used my 7970 higher than 72 bits only very seldom, but the effort to fix the tool and the recognizing of own slips, this scales very high in my book!)
 2015-03-20, 19:38 #1293 tului   Jan 2013 1048 Posts My Beema(A8-6410) takes a crap trying to run mfakto built from the github source. Is there a linux binary available or any tests and log files you'd like me to run on my builds?
2015-03-25, 00:23   #1294
Bdot

Nov 2010
Germany

25516 Posts

Quote:
 Originally Posted by tului My Beema(A8-6410) takes a crap trying to run mfakto built from the github source. Is there a linux binary available or any tests and log files you'd like me to run on my builds?
Sorry to say, but I currently have no time to really help here, especially when the error description is as vage as "takes a crap" (I could not find this string in the source code).

 2015-03-25, 04:13 #1295 tului   Jan 2013 10001002 Posts I was asking if there is any -st -st2 type stuff you'd like me to log and report back.Of course I can give you the exact error message as well. Wasn't thinking about that when I posted.
2015-03-25, 18:33   #1296
TheMawn

May 2013
East. Always East.

11·157 Posts

Quote:
 Originally Posted by Bdot "takes a crap" (I could not find this string in the source code).

2015-03-26, 11:44   #1297
tului

Jan 2013

6810 Posts

Quote:
 Originally Posted by TheMawn
We could always do a git merge :-P

 2015-05-02, 05:32 #1298 frmky     Jul 2003 So Cal 23·32·29 Posts I tried playing with this a bit today, but I'm getting an error: Code: mfakto 0.15pre5 (64bit build) Runtime options Inifile mfakto.ini Verbosity 1 SieveOnGPU yes MoreClasses yes GPUSievePrimes 81157 GPUSieveProcessSize 24Ki bits GPUSieveSize 96Mi bits FlushInterval 0 WorkFile worktodo.txt ResultsFile results.txt Checkpoints enabled CheckpointDelay 300s Stages enabled StopAfterFactor class PrintMode compact V5UserID none ComputerID none TimeStampInResults yes VectorSize 2 GPUType AUTO SmallExp no UseBinfile mfakto_Kernels.elf Compiletime options DEBUG_FACTOR_FIRST enabled (DEBUG option) Select device - Get device info: OpenCL device info name Hawaii (Advanced Micro Devices, Inc.) device (driver) version OpenCL 2.0 AMD-APP (1642.5) (1642.5 (VM)) maximum threads per block 256 maximum threads per grid 16777216 number of multiprocessors 44 (2816 compute elements) clock rate 1000MHz Automatic parameters threads per grid 0 optimizing kernels for GCN3 Loading binary kernel file mfakto_Kernels.elf Compiling kernels. Started a simple selftest ... ERROR: selftest failed for M1031831 (cl_barrett15_69_gs) no factor found Selftest statistics number of tests 30 successful tests 29 no factor found 1 selftest FAILED! Version 0.14 passes both -st and -st2. Is this the error mentioned earlier?

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