speed up imports?

It looks like most of the time is being taken up by pytz (timezone library), which opens ~500 files. How does the total time of "import pytz" compare?

Mike

Andrew Kelly wrote:

···

I see. I was wondering why it spit out a binary file.

test.out is attached...

-Andy

On Fri, Apr 2, 2010 at 10:55 AM, Michael Droettboom <mdroe@…86… > <mailto:mdroe@…86…>> wrote:

    Can you provide the actual saved profiler data? The output of the
    command itself doesn't provide enough information to diagnose the
    problem, since it doesn't have full file paths etc.

    When you do (thanks G�khan for the less verbose version):

     python.exe -c "import cProfile; cProfile.run('import pylab',
    'test.out')"

    this should produce a binary file "test.out" that can be loaded
    with the pstats module and used by GUI tools such as KCacheGrind
    to help us get to the bottom of this.

    Mike

    Andrew Kelly wrote:

        I'm back.

        My backend is wx. "Import wx" does not really take much time
        to import at all. In fact time.time() before and after = 0.0

        Some computer details:
        Processor: AMD Phenom IIx4 810 Processor 2.6 GHz
        RAM: 8.00 GB

        As for the cProfiler output on pylab, I have attached the
        output as test.txt.
         -Andy

        On Fri, Apr 2, 2010 at 7:22 AM, G�khan Sever > <gokhansever@…287… <mailto:gokhansever@…287…> > <mailto:gokhansever@…287…>> > wrote:

           On Fri, Apr 2, 2010 at 8:28 AM, Michael Droettboom > <mdroe@…86… <mailto:mdroe@…86…> > <mailto:mdroe@…86…>> wrote:

               My gut says it's probably the GUI framework import that is
               dominating
               the time. Which backend are you using? Does importing it
               take a large
               amount of time as well?

               Can you provide a profiler output file we can examine
        to narrow it
               down? The following from a command prompt should be
               sufficient to write
               out a file called "import.prof":

                python.exe -c "import cProfile; prof=cProfile.Profile();
               prof.run('import pylab', 'import.prof')"

               Mike

           Just for the records,

           It reads as:

           python -c "import cProfile; cProfile.run('import pylab',
           filename='test.out')

           in Python 2.6.2

           These helped me to load the profile output:

           import pstats
           stats = pstats.Stats("test.out")
           stats.print_stats()

           -- G�khan

                  ------------------------------------------------------------------------------
           Download Intel&#174; Parallel Studio Eval
           Try the new software tools for yourself. Speed compiling,
        find bugs
           proactively, and fine-tune applications for parallel
        performance.
           See why Intel Parallel Studio got high marks during beta.
           http://p.sf.net/sfu/intel-sw-dev
           _______________________________________________
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           https://lists.sourceforge.net/lists/listinfo/matplotlib-users

    -- Michael Droettboom
    Science Software Branch
    Operations and Engineering Division
    Space Telescope Science Institute
    Operated by AURA for NASA

--
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA

import pytz only took 0.0 seconds.

I actually just ran that pstats module and there is one line that stuck out at me:

ncalls tottime percall cumtime percall filename:lineno(function)

1 0.000 0.000 0.000 0.000 C:\Python26\lib\os.py:35(_get_exports_list)
560 3.107 0.006 3.107 0.006 {open}

That is ~50% of the load time. I have 0 idea what this is though.

Let me try this on my os machine…

-Andy

···

On Fri, Apr 2, 2010 at 12:31 PM, Michael Droettboom <mdroe@…86…> wrote:

It looks like most of the time is being taken up by pytz (timezone library), which opens ~500 files. How does the total time of “import pytz” compare?

Mike

Andrew Kelly wrote:

I see. I was wondering why it spit out a binary file.

test.out is attached…

-Andy

On Fri, Apr 2, 2010 at 10:55 AM, Michael Droettboom <mdroe@…86… mailto:mdroe@...86...> wrote:

Can you provide the actual saved profiler data? The output of the
command itself doesn’t provide enough information to diagnose the
problem, since it doesn’t have full file paths etc.

When you do (thanks Gökhan for the less verbose version):

python.exe -c "import cProfile; cProfile.run('import pylab',

‘test.out’)"

this should produce a binary file “test.out” that can be loaded
with the pstats module and used by GUI tools such as KCacheGrind

to help us get to the bottom of this.

Mike

Andrew Kelly wrote:

   I'm back.

   My backend is wx.  "Import wx" does not really take much time
   to import at all.  In fact time.time() before and after = 0.0


   Some computer details:
   Processor: AMD Phenom IIx4 810 Processor 2.6 GHz
   RAM: 8.00 GB

   As for the cProfiler output on pylab, I have attached the
   output as test.txt.

    -Andy

   On Fri, Apr 2, 2010 at 7:22 AM, Gökhan Sever
   <gokhansever@...287... <mailto:gokhansever@...287...>

<mailto:gokhansever@…287… mailto:gokhansever@...287...>>

   wrote:



      On Fri, Apr 2, 2010 at 8:28 AM, Michael Droettboom > >           <mdroe@...86... <mailto:mdroe@...878....86...> > > <mailto:mdroe@...86... <mailto:mdroe@...86...>>> wrote:

          My gut says it's probably the GUI framework import that is

          dominating
          the time.  Which backend are you using?  Does importing it
          take a large
          amount of time as well?

          Can you provide a profiler output file we can examine

   to narrow it
          down?  The following from a command prompt should be
          sufficient to write
          out a file called "import.prof":

           python.exe -c "import cProfile; prof=cProfile.Profile();

          prof.run('import pylab', 'import.prof')"

          Mike


      Just for the records,

      It reads as:

      python -c "import cProfile; cProfile.run('import pylab',

      filename='test.out')

      in Python 2.6.2

      These helped me to load the profile output:

      import pstats
      stats = pstats.Stats("test.out")

      stats.print_stats()

      --     Gökhan

             ------------------------------------------------------------------------------
      Download Intel&#174; Parallel Studio Eval

      Try the new software tools for yourself. Speed compiling,
   find bugs
      proactively, and fine-tune applications for parallel
   performance.
      See why Intel Parallel Studio got high marks during beta.

      [http://p.sf.net/sfu/intel-sw-dev](http://p.sf.net/sfu/intel-sw-dev)
      _______________________________________________
      Matplotlib-users mailing list
      Matplotlib-users@...1739...ge.net

   <mailto:Matplotlib-users@lists.sourceforge.net>
      <mailto:Matplotlib-users@lists.sourceforge.net

   <mailto:Matplotlib-users@lists.sourceforge.net>>

      [https://lists.sourceforge.net/lists/listinfo/matplotlib-users](https://lists.sourceforge.net/lists/listinfo/matplotlib-users)

– Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA


Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA

Andrew Kelly wrote:

import pytz only took 0.0 seconds.

Sounds like it was already imported, so you were not really timing that import.

On linux (ubuntu 9.10, Lenovo T60 laptop) importing pytz takes longer than importing numpy:

efiring@...2091...:~$ time python -c "import pytz"

real 0m0.203s
user 0m0.144s
sys 0m0.052s
efiring@...2091...:~$ time python -c "import pylab"

real 0m0.626s
user 0m0.480s
sys 0m0.124s

efiring@...2091...:~$ time python -c "import numpy"

real 0m0.113s
user 0m0.088s
sys 0m0.020s

(Probably everything is in cache in these tests; repeats yielded similar results.)

Eric

···

I actually just ran that pstats module and there is one line that stuck out at me:
      ncalls tottime percall cumtime percall filename:lineno(function)
        1 0.000 0.000 0.000 0.000 C:\Python26\lib\os.py:35(_get_exports_list)
      560 3.107 0.006 3.107 0.006 {open}
That is ~50% of the load time. I have 0 idea what this is though.
Let me try this on my os machine.....
-Andy

On Fri, Apr 2, 2010 at 12:31 PM, Michael Droettboom <mdroe@…86… > <mailto:mdroe@…86…>> wrote:

    It looks like most of the time is being taken up by pytz (timezone
    library), which opens ~500 files. How does the total time of
    "import pytz" compare?

    Mike

    Andrew Kelly wrote:

        I see. I was wondering why it spit out a binary file.

        test.out is attached...

        -Andy

        On Fri, Apr 2, 2010 at 10:55 AM, Michael Droettboom > <mdroe@…86… <mailto:mdroe@…86…> > <mailto:mdroe@…86…>> wrote:

           Can you provide the actual saved profiler data? The output
        of the
           command itself doesn't provide enough information to diagnose the
           problem, since it doesn't have full file paths etc.

           When you do (thanks Gökhan for the less verbose version):

            python.exe -c "import cProfile; cProfile.run('import pylab',
           'test.out')"

           this should produce a binary file "test.out" that can be loaded
           with the pstats module and used by GUI tools such as KCacheGrind
           to help us get to the bottom of this.

           Mike

           Andrew Kelly wrote:

               I'm back.

               My backend is wx. "Import wx" does not really take much time
               to import at all. In fact time.time() before and after = 0.0

               Some computer details:
               Processor: AMD Phenom IIx4 810 Processor 2.6 GHz
               RAM: 8.00 GB

               As for the cProfiler output on pylab, I have attached the
               output as test.txt.
                -Andy

               On Fri, Apr 2, 2010 at 7:22 AM, Gökhan Sever
               <gokhansever@…287… <mailto:gokhansever@…287…>
        <mailto:gokhansever@…287…>
               <mailto:gokhansever@…287…
        <mailto:gokhansever@…287…> <mailto:gokhansever@…287…
        <mailto:gokhansever@…287…>>>>

               wrote:

                  On Fri, Apr 2, 2010 at 8:28 AM, Michael Droettboom > <mdroe@…86… <mailto:mdroe@…86…> > <mailto:mdroe@…86…> > <mailto:mdroe@…86… > <mailto:mdroe@…86…>>> wrote:

                      My gut says it's probably the GUI framework import
        that is
                      dominating
                      the time. Which backend are you using? Does
        importing it
                      take a large
                      amount of time as well?

                      Can you provide a profiler output file we can examine
               to narrow it
                      down? The following from a command prompt should be
                      sufficient to write
                      out a file called "import.prof":

                       python.exe -c "import cProfile;
        prof=cProfile.Profile();
                      prof.run('import pylab', 'import.prof')"

                      Mike

                  Just for the records,

                  It reads as:

                  python -c "import cProfile; cProfile.run('import pylab',
                  filename='test.out')

                  in Python 2.6.2

                  These helped me to load the profile output:

                  import pstats
                  stats = pstats.Stats("test.out")
                  stats.print_stats()

                  -- Gökhan

                                ------------------------------------------------------------------------------
                  Download Intel&#174; Parallel Studio Eval
                  Try the new software tools for yourself. Speed compiling,
               find bugs
                  proactively, and fine-tune applications for parallel
               performance.
                  See why Intel Parallel Studio got high marks during beta.
                  http://p.sf.net/sfu/intel-sw-dev
                  _______________________________________________
                  Matplotlib-users mailing list
                  Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>
               <mailto:Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>>
                  <mailto:Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>
               <mailto:Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>>>

                         https://lists.sourceforge.net/lists/listinfo/matplotlib-users

           -- Michael Droettboom
           Science Software Branch
           Operations and Engineering Division
           Space Telescope Science Institute
           Operated by AURA for NASA

    -- Michael Droettboom
    Science Software Branch
    Operations and Engineering Division
    Space Telescope Science Institute
    Operated by AURA for NASA

------------------------------------------------------------------------

------------------------------------------------------------------------------
Download Intel&#174; Parallel Studio Eval
Try the new software tools for yourself. Speed compiling, find bugs
proactively, and fine-tune applications for parallel performance.
See why Intel Parallel Studio got high marks during beta.
http://p.sf.net/sfu/intel-sw-dev

------------------------------------------------------------------------

_______________________________________________
Matplotlib-users mailing list
Matplotlib-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Slow on my OSX machine as well. I also get this strange warning which I have never seen before (I usually only use MPL on my windows machine).

Warning (from warnings module):

File “/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/pytz/init.py”, line 29

from pkg_resources import resource_stream

UserWarning: Module numpy was already imported from /Library/Frameworks/GDAL.framework/Versions/1.6/Python/site-packages/numpy/init.pyc, but /Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages is being added to sys.path

···

On Fri, Apr 2, 2010 at 1:41 PM, Eric Firing <efiring@…202…> wrote:

Andrew Kelly wrote:

import pytz only took 0.0 seconds.

Sounds like it was already imported, so you were not really timing that import.

On linux (ubuntu 9.10, Lenovo T60 laptop) importing pytz takes longer than importing numpy:

efiring@…2091…:~$ time python -c “import pytz”

real 0m0.203s

user 0m0.144s

sys 0m0.052s

efiring@…2091…:~$ time python -c “import pylab”

real 0m0.626s

user 0m0.480s

sys 0m0.124s

efiring@…2091…:~$ time python -c “import numpy”

real 0m0.113s

user 0m0.088s

sys 0m0.020s

(Probably everything is in cache in these tests; repeats yielded similar results.)

Eric

I actually just ran that pstats module and there is one line that stuck out at me:

  ncalls  tottime  percall  cumtime  percall filename:lineno(function)

    1    0.000    0.000    0.000    0.000 C:\Python26\lib\os.py:35(_get_exports_list)

  560    3.107    0.006    3.107    0.006 {open}

That is ~50% of the load time. I have 0 idea what this is though.

Let me try this on my os machine…

-Andy

On Fri, Apr 2, 2010 at 12:31 PM, Michael Droettboom <mdroe@…86… mailto:mdroe@...86...> wrote:

It looks like most of the time is being taken up by pytz (timezone

library), which opens ~500 files.  How does the total time of

"import pytz" compare?



Mike



Andrew Kelly wrote:



    I see.  I was wondering why it spit out a binary file.



    test.out is attached...



    -Andy



    On Fri, Apr 2, 2010 at 10:55 AM, Michael Droettboom > >  > >         <mdroe@...86... <mailto:mdroe@...86...> > > <mailto:mdroe@...86... <mailto:mdroe@...86...>>> wrote:

Can you provide the actual saved profiler data? The output

    of the

       command itself doesn't provide enough information to diagnose the

       problem, since it doesn't have full file paths etc.



       When you do (thanks Gökhan for the less verbose version):



        python.exe -c "import cProfile; cProfile.run('import pylab',

       'test.out')"



       this should produce a binary file "test.out" that can be loaded

       with the pstats module and used by GUI tools such as KCacheGrind

       to help us get to the bottom of this.



       Mike



       Andrew Kelly wrote:



           I'm back.



           My backend is wx.  "Import wx" does not really take much time

           to import at all.  In fact time.time() before and after = 0.0



           Some computer details:

           Processor: AMD Phenom IIx4 810 Processor 2.6 GHz

           RAM: 8.00 GB



           As for the cProfiler output on pylab, I have attached the

           output as test.txt.

            -Andy



           On Fri, Apr 2, 2010 at 7:22 AM, Gökhan Sever

           <gokhansever@...287... <mailto:gokhansever@...287...>

    <mailto:gokhansever@...287... <mailto:gokhansever@...287...>>

           <mailto:gokhansever@...287...

    <mailto:gokhansever@...287...> <mailto:gokhansever@...287...

    <mailto:gokhansever@...287...>>>>



           wrote:







              On Fri, Apr 2, 2010 at 8:28 AM, Michael Droettboom

              <mdroe@...86... <mailto:mdroe@...86...>

    <mailto:mdroe@...86... <mailto:mdroe@...86...>>

           <mailto:mdroe@...86... <mailto:mdroe@...86...>

    <mailto:mdroe@...86... <mailto:mdroe@...86...>>>> wrote:



                  My gut says it's probably the GUI framework import

    that is

                  dominating

                  the time.  Which backend are you using?  Does

    importing it

                  take a large

                  amount of time as well?



                  Can you provide a profiler output file we can examine

           to narrow it

                  down?  The following from a command prompt should be

                  sufficient to write

                  out a file called "import.prof":



                   python.exe -c "import cProfile;

    prof=cProfile.Profile();

                  prof.run('import pylab', 'import.prof')"



                  Mike





              Just for the records,



              It reads as:



              python -c "import cProfile; cProfile.run('import pylab',

              filename='test.out')



              in Python 2.6.2



              These helped me to load the profile output:



              import pstats

              stats = pstats.Stats("test.out")

              stats.print_stats()



              --     Gökhan



                            ------------------------------------------------------------------------------

              Download Intel&#174; Parallel Studio Eval

              Try the new software tools for yourself. Speed compiling,

           find bugs

              proactively, and fine-tune applications for parallel

           performance.

              See why Intel Parallel Studio got high marks during beta.

              [http://p.sf.net/sfu/intel-sw-dev](http://p.sf.net/sfu/intel-sw-dev)

              _______________________________________________

              Matplotlib-users mailing list

              Matplotlib-users@lists.sourceforge.net

    <mailto:Matplotlib-users@lists.sourceforge.net>

           <mailto:Matplotlib-users@...1738....net

    <mailto:Matplotlib-users@lists.sourceforge.net>>

              <mailto:Matplotlib-users@...1544...ceforge.net

    <mailto:Matplotlib-users@lists.sourceforge.net>

           <mailto:Matplotlib-users@...1738....net

    <mailto:Matplotlib-users@lists.sourceforge.net>>>



                     [https://lists.sourceforge.net/lists/listinfo/matplotlib-users](https://lists.sourceforge.net/lists/listinfo/matplotlib-users)







       --     Michael Droettboom

       Science Software Branch

       Operations and Engineering Division

       Space Telescope Science Institute

       Operated by AURA for NASA







--     Michael Droettboom

Science Software Branch

Operations and Engineering Division

Space Telescope Science Institute

Operated by AURA for NASA


Download Intel® Parallel Studio Eval

Try the new software tools for yourself. Speed compiling, find bugs

proactively, and fine-tune applications for parallel performance.

See why Intel Parallel Studio got high marks during beta.

http://p.sf.net/sfu/intel-sw-dev



Matplotlib-users mailing list

Matplotlib-users@lists.sourceforge.net

https://lists.sourceforge.net/lists/listinfo/matplotlib-users

All of those calls to "open" are being generated from the pytz import -- which is why pytz seems like the likely candidate. Is it possible you have pytz installed as a compressed egg, or on a remote disk, or something that may be causing a file reading penalty?

As Eric said, make sure you time the "import pytz" in a clean Python session -- if a module is already imported in the Python interpreter, it won't be reimported.

Mike

Andrew Kelly wrote:

···

import pytz only took 0.0 seconds.
I actually just ran that pstats module and there is one line that stuck out at me:
      ncalls tottime percall cumtime percall filename:lineno(function)
        1 0.000 0.000 0.000 0.000 C:\Python26\lib\os.py:35(_get_exports_list)
      560 3.107 0.006 3.107 0.006 {open}
That is ~50% of the load time. I have 0 idea what this is though.
Let me try this on my os machine.....
-Andy

On Fri, Apr 2, 2010 at 12:31 PM, Michael Droettboom <mdroe@…86… > <mailto:mdroe@…86…>> wrote:

    It looks like most of the time is being taken up by pytz (timezone
    library), which opens ~500 files. How does the total time of
    "import pytz" compare?

    Mike

    Andrew Kelly wrote:

        I see. I was wondering why it spit out a binary file.

        test.out is attached...

        -Andy

        On Fri, Apr 2, 2010 at 10:55 AM, Michael Droettboom > <mdroe@…86… <mailto:mdroe@…86…> > <mailto:mdroe@…86…>> wrote:

           Can you provide the actual saved profiler data? The output
        of the
           command itself doesn't provide enough information to
        diagnose the
           problem, since it doesn't have full file paths etc.

           When you do (thanks G�khan for the less verbose version):

            python.exe -c "import cProfile; cProfile.run('import pylab',
           'test.out')"

           this should produce a binary file "test.out" that can be loaded
           with the pstats module and used by GUI tools such as
        KCacheGrind
           to help us get to the bottom of this.

           Mike

           Andrew Kelly wrote:

               I'm back.

               My backend is wx. "Import wx" does not really take
        much time
               to import at all. In fact time.time() before and after
        = 0.0

               Some computer details:
               Processor: AMD Phenom IIx4 810 Processor 2.6 GHz
               RAM: 8.00 GB

               As for the cProfiler output on pylab, I have attached the
               output as test.txt.
                -Andy

               On Fri, Apr 2, 2010 at 7:22 AM, G�khan Sever
               <gokhansever@…287… <mailto:gokhansever@…287…>
        <mailto:gokhansever@…287…>
               <mailto:gokhansever@…287…
        <mailto:gokhansever@…287…> <mailto:gokhansever@…287…
        <mailto:gokhansever@…287…>>>>

               wrote:

                  On Fri, Apr 2, 2010 at 8:28 AM, Michael Droettboom > <mdroe@…86… <mailto:mdroe@…86…> > <mailto:mdroe@…86…> > <mailto:mdroe@…86… > <mailto:mdroe@…86…>>> wrote:

                      My gut says it's probably the GUI framework
        import that is
                      dominating
                      the time. Which backend are you using? Does
        importing it
                      take a large
                      amount of time as well?

                      Can you provide a profiler output file we can
        examine
               to narrow it
                      down? The following from a command prompt should be
                      sufficient to write
                      out a file called "import.prof":

                       python.exe -c "import cProfile;
        prof=cProfile.Profile();
                      prof.run('import pylab', 'import.prof')"

                      Mike

                  Just for the records,

                  It reads as:

                  python -c "import cProfile; cProfile.run('import pylab',
                  filename='test.out')

                  in Python 2.6.2

                  These helped me to load the profile output:

                  import pstats
                  stats = pstats.Stats("test.out")
                  stats.print_stats()

                  -- G�khan

                                ------------------------------------------------------------------------------
                  Download Intel&#174; Parallel Studio Eval
                  Try the new software tools for yourself. Speed
        compiling,
               find bugs
                  proactively, and fine-tune applications for parallel
               performance.
                  See why Intel Parallel Studio got high marks during
        beta.
                  http://p.sf.net/sfu/intel-sw-dev
                  _______________________________________________
                  Matplotlib-users mailing list
                  Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>
               <mailto:Matplotlib-users@lists.sourceforge.net
        <mailto:Matplotlib-users@lists.sourceforge.net>>
                  <mailto:Matplotlib-users@lists.sourceforge.net
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           -- Michael Droettboom
           Science Software Branch
           Operations and Engineering Division
           Space Telescope Science Institute
           Operated by AURA for NASA

    -- Michael Droettboom
    Science Software Branch
    Operations and Engineering Division
    Space Telescope Science Institute
    Operated by AURA for NASA

--
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA

Michael Droettboom wrote:

All of those calls to "open" are being generated from the pytz import -- which is why pytz seems like the likely candidate. Is it possible you have pytz installed as a compressed egg, or on a remote disk, or something that may be causing a file reading penalty?

Mike,

The pytz import time, at nearly 1/3 of the total mpl import time, is crazy even on linux, given that it adds only a tiny bit of functionality, and as far as I can see, even that is only rarely used.

Therefore I have committed a change so that it is imported only if and when it is required. Our examples still work, after I modified one that was trying to import timezone from mpl.dates (although it was not actually using timezone). This probably illustrates the way in which this change may break some user code: user programs requiring pytz.timezone and pytz.tzinfo will have to import them directly instead of getting them from mpl.dates. I hope this is acceptable; importing them from mpl.dates seems like bad practice anyway, since mpl.dates was not using them or modifying them but was just passing them on from pytz.

I suspect pytz could be redesigned so that it would not be so horrendously slow to import, but I am not going to tackle that.

After the change:

efiring@...2091...:~$ time python -c "import pylab"

real 0m0.441s
user 0m0.372s
sys 0m0.064s

Before the change:

efiring@...2091...:~$ time python -c "import pylab"

real 0m0.626s
user 0m0.480s
sys 0m0.124s

Again, this is recent linux on a 3-year-old laptop.

Eric

···

As Eric said, make sure you time the "import pytz" in a clean Python session -- if a module is already imported in the Python interpreter, it won't be reimported.

Mike