New features in Version
23.8 of prime95.exe
- A communication bug, Primenet
Error 1, was fixed in the case where proxy software inserted the text
"NetAnts: MaxConnection=1" in the HTML response from the
Primenet server.
- Fixed memory allocation bug in
torture test when using 926MB of memory on the 20K FFT size.
3. The
program will now try both full and a relative URL in trying to contact the
PrimeNet server. Some rare setups only
work with full URLs and some only work with relative URLs. The small downside is there might be an
increase in network traffic when the server is down. If this is a concern you can use the UseFullURL option described
in undoc.txt.
New features in Version 23.7
of prime95.exe
- A bug was fixed where the
torture test used more virtual memory than necessary, sometimes resulting
in an "Out of memory" error.
New features in Version
23.6 of prime95.exe
- Several changes have been made
to the torture test.
a)
Machines
faster than 1 GHz will use new test data that runs a lot more iterations. This will reduce time spent in
initialization code, hopefully increasing stress on the CPU.
b)
The
torture test stops after 100 ILLEGAL SUMOUT errors.
c)
There
are now 3 flavors of torture testing.
One that operates on small FFTs only, theoretically maximizing FPU
stress. One that operates in place on
large FFTs only, maximizing heat and power drain. One that runs a blend of tests using lots of memory, possibly
catching errors that might only occur at a specific memory address.
New features in Version
23.5 of prime95.exe
- Four changes have been made
after GIMPS' first false positive report in 7 1/2 years of operation.
a)
The
program now returns the number of errors that occurred when the result is
prime. A non-zero value will make us
more suspect of the reported prime.
b)
The
save files will not be deleted. The
user can then email these to me and we can rerun the last 30 minutes of the LL
test. It is hard to imagine a second
false positive report in this mini LL run.
c)
The
shift counter is now checked every iteration.
If this variable AND the FFT data was corrupted, then and endless loop
of LL iterations generating zero is possible - resulting in a false prime
report.
d)
Every
iteration the FFT data is checked to see if the data has been zeroed.
e)
The
is-this-a-prime check now makes sure the FFT data is not NaN. NaN stands for not a number and means the
data is corrupt. The previous version
checked for zero and my C compiler returns TRUE for the test NaN == 0.0!
- I restored the old behavior
sending relative URLs. Some users
had trouble with this feature introduced in 23.4. So, UseFullURL=0 is now the default.
- Some prefetching improvements
were made for the Athlon, Pentium 3, and Celeron 2 processors. You can expect speed improvements
between 3% and 10% for most FFT sizes.
Warning: the new code is slower for Durons and Celeron's with small
L2 caches for FFT sizes 1024K and above.
New features in Version
23.4 of prime95.exe
- Further performance
improvements in the SSE2 FFT code.
I've tried to do more work while data is in the L1 data cache.
- The program should now work
with a "redirected proxy server". This was done by sending full URLs in Primenet
requests. While I don't anticipate
any problems, the old relative URL functionality can be had by setting
UseFullURL=0 in primenet.ini.
- A bug in the assembly language
add and subtract routines was fixed.
The bug could affect ECM on exponents just below
MAXIMUM_EXPONENT_FOR_FFTLEN - FFTLEN/2.
New features in Version
23.3 of prime95.exe
- Further performance
improvements in the SSE2 code for FFTs larger than 640K. You should see about a 4% improvement
in LL tests on a P4. However, FFTs
between 40K and 512K might be a tiny bit slower.
- Stage 2 of P-1 factoring has
been recoded for more speed.
WARNING: when continuing from a save file created in stage 2 by a
previous prime95 version, this version will restart stage 2 from the
beginning. ALSO: the stage 2 P-1
save file format has changed - in dual boot scenarios you must upgrade
mprime and prime95 at the same time.
New features in Version
23.2 of prime95.exe
- Further
performance improvements in the SSE2 code. You can expect about a 4% improvement.
New features in Version
23.1 of prime95.exe
- Big SSE2
FFTs now take the L2 cache size into account. P4 Celeron (128KB L2 cache) is faster for FFTs between 512K
and 2M. P4 Northwood (512KB L2
cache) is faster for FFTs larger than 1M.
- Benchmark
no longer times 256K and 320K FFTs, but does time 2048K FFT.
- Support
for torture testing FFT sizes from 1280K to 4096K added.
- A 900
MHz P-III is now required to get first time LL tests by default.
- Slightly
faster SSE2 FFTs for lengths of 5*2^N and 7*2^N (e.g. 640K, 896K).