S40.03 Observations

M. Schmitt
M. Schmitt
Joined: 27 Jun 05
Posts: 478
Credit: 15872262
RAC: 0

RE: Thanks for the heads

Message 27730 in response to message 27729

Quote:
Thanks for the heads up! I will keep a sharper eye on the results, and if they start to not validate I will switch back to D40 (which worked very well).

You can also switch back to S40, that's almost as fast(~0.9% diff.) as S40.03, but faster than D40.

cu,
Michael

_heinz
_heinz
Joined: 4 Jan 06
Posts: 79
Credit: 130476
RAC: 0

Today I tried the S40.03, it

Today I tried the S40.03, it worked fine. Here are the last 3 WU CPU-Times
5,279.44
5,189.41
5,132.86
Before that I used S39L, but I can find no big difference, between them.
Mayby S40.03 is 100 ~ 200 seconds faster
I used a Pentium 2,6GHz

Or is the S40.03 still for Athlon CPU´s ?


Akos Fekete
Akos Fekete
Joined: 13 Nov 05
Posts: 561
Credit: 4527270
RAC: 0

RE: Once you might get WUs

Message 27732 in response to message 27728

Quote:

Once you might get WUs of a different frequency and then the scheduler will throw away your results.
My X2 did't have a problem so far, but they may come and the XP also crunched very well, until z1_1373.5 showed up.

Let's see what akos is gonna answer.

Albert uses a very low precision sin/cos look-up table. The rounding at its address generation enlarges the deviations.

example:

before "low precision" operation:
value(S40.03)=0.416723851
value(original)=0.416723849
deviation: 0,00000048%

after "low precision" operation:
value(S40.03)=0.423156123
values(original)=0.40853772
deviation: 3,58% (cca. 7500000 more times bigger difference)

I will modify this part if I will found some free hours.

edit: This rounding problem appears infrequently, but if it appears that means a big problem... (zero credit)

Robbie McMichael
Robbie McMichael
Joined: 11 Mar 06
Posts: 3
Credit: 2797421
RAC: 0

S40.03 works brilliantly for

S40.03 works brilliantly for me. S39L for some reason was about 3 times slower than C40 on my machine, so I was running C40 for a while. S40.03 seems to take about two thirds of the time for a WU when compared to C40, so thanks for the optimized app Akosf :)

Stick
Stick
Joined: 24 Feb 05
Posts: 790
Credit: 33132401
RAC: 1101

RE: RE: S40.04 - SSE

Quote:
Quote:
S40.04 - SSE optimised windows executable

Comment: bugfixed version of S40.03 (zero credit problem)

Akos,

Thank you! (A much better answer than the one Bruce gave me.)

Stick

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.