At 10:08 AM 8/2/2008, Alan Gauld wrote:
"Dick Moores" <[EMAIL PROTECTED]> wrote
BTW Kent, I'm going to take this opportunity to ask you about
"System" in the IPython timing results. It's always zero for the
code I time. What's an example of code that would have System be
greater than zero? And what's the distinction between User and
System? (I'm using Win XP, if that's relevant.)
In timing user time is time that the CPU spends executing user
code - your program. System time is time the CPU spends doing
OS things.
If your code had a blocking call that waited for input on a port say,
then the OS might be doing other stuff in the background while
your code waited. This would show as system time.
In some OR even time spent reading files from disk is
counted as system time because your code is executing
low level OS functions.
Try timing a function that does nothing but read a large file.
See if there is any system time showing up.
Well, here's one that reads in the text of Dickens' _Little Dorrit_
and returns the word count:
In [11]: run -t -N10 timing_test_little_dorrit.py
339832
339832
339832
339832
339832
339832
339832
339832
339832
339832
IPython CPU timings (estimated):
Total runs performed: 10
Times : Total Per run
User : 5.94446752311 s, 0.594446752311 s.
System: 0.0 s, 0.0 s.
Or time a GUI
app that waits for user input...
This one is a Gui that has an Exit button. I called it and then hit the button:
In [4]: run -t ToolkitV15.py
IPython CPU timings (estimated):
User : 10.5294301371 s.
System: 0.0 s.
So no non-zero System time yet. But thanks for your explanation.
Dick
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