in reply to Re^3: In search of a bug in Time::HiRes on Windows.
in thread In search of a bug in Time::HiRes on Windows.

As with ikegami above, you are running with a very old version (1.2) of Time::HiRes. To get better resolution, you will need to install 1.53 or later. For the purposes of tracking down the bug I think I have found, it would be useful to me if you would perform the following three steps:

  1. Install v1.53 or later (but don't run (n)make test).

    I have a zip that contains the required files for 1.59 I can email if that is more convenient.

  2. Having installed ( but not run the test suite ), re-run the test program from the OP.

    If you immediately see much higher resolution (differences between successive output in 10s of microseconds rather than 100s of milliseconds) results, stop there (but inform me please :).

    My speculation is that an extra step is required beyond just installing and using Time::HiRes (>1.53), in order for the high performance timer code to become enabled.

  3. If you do not immediately see better resolution. /Msg me and I'll give you the program that I think will enable HPC code in T::HR.

The problem with this is that once the HPC code is enabled, I have not been able to revert to the non-enabled state. It appears that some action is required to enable the HPC code, but once it has been enabled it remains enabled across reboots. (I haven't tried a re-install!).

Thanks for your help.

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Re^5: In search of a bug in Time::HiRes on Windows.
by fglock (Vicar) on Jun 16, 2005 at 17:39 UTC

    This is what I got (with NT/5.8.0):

    # original version:
  H:\temp>perl x.pl
  1.2

# with the new library:
  H:\temp>perl -Ilib x.pl
  1.49

# I modified the program to accept a parameter
# and tried again
  H:\temp>perl -Ilib x.pl 10
  1.49 - 10 times

# this only happened once!
  H:\temp>perl x.pl 10
  1.2 - 10 times
  1118932187.88553
  1118932187.94562
  1118932188.0057
  1118932188.06579
  1118932188.13589

  H:\temp>perl -Ilib x.pl 10
  1.49 - 10 times

# then tried again a few times
  H:\temp>perl x.pl 10 & perl -Ilib x.pl 10
  1.2 - 10 times
  1.49 - 10 times

    [download]

    With "100", sometimes I get output in version 1.2, sometimes not; there is no output in version 1.49

    With "1000", I got output in both versions.

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