I seriously doubt that threading would do anything positive for you.

That's the trouble with not having the skills or capability to do your own research; you're always left regurgitating someone else's knowledge, even when it is out-of-date.

Here are the results of multi-threading a search of an 8GB file on a 4-core machine:

[20:39:41.83] C:\test>1131634.pl -T=1 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 207.819706917 secs cpu(162.296 15.906 0 0)
[20:43:09.82] C:\test>1131634.pl -T=2 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 169.678593159 secs cpu(164.203 18.968 0 0)
[20:46:00.25] C:\test>1131634.pl -T=3 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 156.497795820 secs cpu(164.375 18.656 0 0)
[20:48:37.34] C:\test>1131634.pl -T=4 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 127.086592913 secs cpu(161.843 19.546 0 0)
[20:50:45.04] C:\test>1131634.pl -T=5 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 115.240671158 secs cpu(161.89 19.109 0 0)
[20:52:40.87] C:\test>1131634.pl -T=6 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 129.716307163 secs cpu(161.781 21.859 0 0)
[20:54:51.19] C:\test>1131634.pl -T=7 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 167.007865906 secs cpu(162.328 22.171 0 0)
[20:57:38.78] C:\test>1131634.pl -T=8 s:\1GBx8.bin lAxc
Found 10 'lAxc' lines Took 179.142831087 secs cpu(164.171 25.546 0 0)


      210   ---
  E   200   ...                               165.0
  l   190   ...                               164.8
  a   180   ...                         ___   164.6
  p   170   ... ___  X                  ...   164.4    C
  s   160   ... .X.                 --- .X.   164.2    P
  e   150   ... ... ---             ... ...   164.0    U
  d   140   ... ... ...         ___ ... ...   163.8
      130   ... ... ...         ... ... ...   163.6    S
  s   120   ... ... ... ---     ... ... ...   163.4    e
  e   110   ... ... ... ... --- ... ... ...   163.2    c
  c   100   .X. ... ... ... ... ... ... ...   163.0    o
  o    90   ... ... ... ... ... ... ... ...   162.8    n
  n    80   ... ... ... ... ... ... ... ...   162.6    d
  d    70   ... ... ... ... ... ... .X. ...   162.4    s
  s    60   ... ... ... ... ... ... ... ...   162.2    .
  .    50   ... ... ... ... ... ... ... ...   162.0
       40   ... ... ... .X. .X. .X. ... ...   161.8
       30   ... ... ... ... ... ... ... ...   161.6
       20   ... ... ... ... ... ... ... ...   161.4
       10   ... ... ... ... ... ... ... ...   161.2
             1   2   3   4   5   6   7   8
               T   H   R   E   A   D   S

[download]

With 5 threads, it almost halves the time and and even reduces the overall cpu usage slightly.

The only question left is why do you bother to continue to play the Village Idiot™, and I think finally the answer to that conundrum is becoming self-evident.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!

In reply to Re^2: How to split file for threading? by BrowserUk
in thread How to split file for threading? by diyaz

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