Prime95 30.7

[Minty]

8600K Coffee Lake CPU, 1 worker, 6 threads. FMA3 FFT (6400K), 117M exponent: stage 1 = 72.8 sec, stage 2 = 116.6 sec

[tha]

Don't know yet if this is reproducable, I will try later. But mprime hangs on timing FFT's. I pressed ^C at 08:37 as shown in the output. I closed the terminal application at 08:40 which made the CPU usage drop from 13% to 2%.

[Work thread Oct 5 05:12] Stage 2 GCD complete. Time: 1.310 sec.
[Work thread Oct 5 05:12] M9201337 completed P-1, B1=2000000, B2=162000000, Wi8: E7C912E0
[Comm thread Oct 5 05:12] Sending result to server: UID: Tha/Z170-m30.7, M9201337 completed P-1, B1=2000000, B2=162000000, Wi8: E7C912E0
[Comm thread Oct 5 05:12] 
[Work thread Oct 5 05:12] 
[Work thread Oct 5 05:12] P-1 on M9203287 with B1=2000000, B2=TBD
[Work thread Oct 5 05:12] Setting affinity to run helper thread 1 on CPU core #2
[Work thread Oct 5 05:12] Using FMA3 FFT length 480K, Pass1=384, Pass2=1280, clm=4, 4 threads
[Work thread Oct 5 05:12] Setting affinity to run helper thread 2 on CPU core #3
[Work thread Oct 5 05:12] Setting affinity to run helper thread 3 on CPU core #4
[Comm thread Oct 5 05:12] PrimeNet success code with additional info:
[Comm thread Oct 5 05:12] CPU credit is 4.2951 GHz-days.
[Comm thread Oct 5 05:12] Done communicating with server.
[Work thread Oct 5 05:15] M9203287 stage 1 is 13.86% complete. Time: 176.025 sec.
[Work thread Oct 5 05:18] M9203287 stage 1 is 27.72% complete. Time: 175.997 sec.
[Work thread Oct 5 05:21] M9203287 stage 1 is 41.58% complete. Time: 175.971 sec.
[Work thread Oct 5 05:24] M9203287 stage 1 is 55.44% complete. Time: 175.988 sec.
[Work thread Oct 5 05:27] M9203287 stage 1 is 69.30% complete. Time: 176.017 sec.
[Work thread Oct 5 05:30] M9203287 stage 1 is 83.17% complete. Time: 175.973 sec.
[Main thread Oct 5 05:32] Benchmarking multiple workers to tune FFT selection.
[Work thread Oct 5 05:32] Worker stopped while running needed benchmarks.
[Main thread Oct 5 05:32] Timing 480K FFT, 4 cores, 1 worker.  ^C[Oct 5 08:37] Stopping all worker windows.


	     Invalid choice

	     Main Menu

	 1.  Test/Primenet
	 2.  Test/Workers
	 3.  Test/Status
	 4.  Test/Continue
	 5.  Test/Exit
	 6.  Advanced/Test
	 7.  Advanced/Time
	 8.  Advanced/P-1
	 9.  Advanced/ECM
	10.  Advanced/Manual Communication
	11.  Advanced/Unreserve Exponent
	12.  Advanced/Quit Gimps
	13.  Options/CPU
	14.  Options/Resource Limits
	15.  Options/Preferences
	16.  Options/Torture Test
	17.  Options/Benchmark
	18.  Help/About
	19.  Help/About PrimeNet Server
Your choice: 5

Waiting for worker threads to stop.
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Waiting for worker threads to stop.
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Waiting for worker threads to stop.
Waiting for worker threads to stop.
Waiting for worker threads to stop.

[kruoli]

Interesting picture on an Intel Atom C2538 doing ECM:

0.7M exponent, type-1 FFT length 40K, 4 threads.
Stage 1: 82 seconds per output
Stage 2: 80 seconds per output

Also, stage 2 is way faster (960 seconds) than stage 1 (3042 seconds), despite B2 being chosen as 146*B1.

[ZacHFX]

This isn't 30.7 specific, but after upgrading to Windows 11 today, I get a significant performance drop in Prime95 unless it is run in Administrator mode. Nearly a 70% drop. Happens in both 30.7b2 and 30.5b2

[Prime95]

Originally Posted by ZacHFX

This isn't 30.7 specific, but after upgrading to Windows 11 today, I get a significant performance drop in Prime95 unless it is run in Administrator mode. Nearly a 70% drop. Happens in both 30.7b2 and 30.5b2

Can you report on how well prime95 is assigning workers to CPU cores? Is Win11 adhering to prime95's affinity settings? This is similar to what my Alder Lake tester reported. Does Win11 have any new power saving settings where it puts CPU hogs like prime95 on slower running cores?

[Prime95]

Originally Posted by tha

Don't know yet if this is reproducable, I will try later. But mprime hangs on timing FFT's. I pressed ^C at 08:37 as shown in the output. I closed the terminal application at 08:40 which made the CPU usage drop from 13% to 2%.

Build 1 or 2? This looks like the bug fixed in build 2.

Originally Posted by pepi37

With Prime95 30.7 b2 I have this problem
On the other side, with Prime95 30.6 build 4 on same configuration

It looks like non-Mersenne FFTs are broken. The bug was introduced when I switched to the C runtime libraries implementation of log2 rather than my own (part of a modernization to the C++11 standard). Still figuring out the exact issue. Will fix as soon as possible.

[firejuggler]

I am pleased to report that PM1 has found a factor and that the prp went without an itch with 30.7 b2

[tha]

Originally Posted by Prime95

Build 1 or 2? This looks like the bug fixed in build 2.

Build 1 indeed.

[kruoli]

Originally Posted by Prime95

[...] Win11 [...]

Windows 11 seems to be always running with Virtualization-Based Security enabled and this will also cost some performance.

[ZacHFX]

Originally Posted by Prime95

Can you report on how well prime95 is assigning workers to CPU cores? Is Win11 adhering to prime95's affinity settings? This is similar to what my Alder Lake tester reported. Does Win11 have any new power saving settings where it puts CPU hogs like prime95 on slower running cores?

Affinity is the same. One exponent running on core 1, helper threads 2 through 8, the other running on core 9, helpers 10 through 16. All cores are in use, so it's not a question of using only the slower cores.

I'm seeing the same performance decrease even while in administrator mode now. But my CPU isn't generating nearly the same amount of heat as it was under win10 either. Restarting the computer and running only prime95 in administrator mode will get nearly the same performance as I had in win10. But it slowly loses performance over the course of an hour.

[Prime95]

Originally Posted by ZacHFX

I'm seeing the same performance decrease even while in administrator mode now. But my CPU isn't generating nearly the same amount of heat as it was under win10 either. Restarting the computer and running only prime95 in administrator mode will get nearly the same performance as I had in win10. But it slowly loses performance over the course of an hour.

Do any of these suggestions help:
https://gadgetstouse.com/blog/2021/0...e-performance/

I'm wondering if Win11 has a new default performance plan that does not run programs like prime95 at full clock speed