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Re: Hydra is FAST [message #2388 is a reply to message #2387]

Mon, 10 April 2006 14:55

mirek
Messages: 14265
Registered: November 2005

Ultimate Member

hojtsy wrote on Mon, 10 April 2006 06:59

I rerun these test. The results seems to vary greatly. In the second run the winner was 2 threads, and in the third run winner was 3 threads but only with a small amount ahead of 2 threads.

1 Thread: 2.30 1.27, 1.30
2 Threads: 2.12, 1.10, 1.14
3 Threads: 2.02 1.13, 1.13
4 Threads: 1:17 1.12, 1.19
5 Threads: 1:13 1.12, 2.52
6 Threads: 1:10 2.32
7 Threads: 1:16
8 Threads: 5:51

I did all these tests the same way, by clicking the bomb icon in the same example after modifying the thread setting. Maybe some of the wild time values could be caused by some files becoming old enough between test runs to used in BLITZ compilations, but even with that the results are quite inconsistent. I suppose this could be tested automatically by compiling with every thread setting 10 times, and averaging, but I don't have the patience for that. Given all this inconsistency the only conclusion I can make is that 2 threads was always faster than 1 thread.

Well, those results look much more believable....

In fact, if you take best resutls, it now looks like 2 and more threads a little bit faster than single one (something one would expect on HT CPU), but not by large margin.

Still, I have not seen compile times so much erratically changing yet....

Mirek

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