os.times() returns incorrect value

[kwatch]

BPO	2205
Nosy	@birkenfeld, @facundobatista
Files	posixmodule.patch: patch to Modules/posixmodule.c

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2008-02-29.02:03:04.772>
created_at = <Date 2008-02-29.01:59:20.315>
labels = ['type-bug', 'library']
title = 'os.times() returns incorrect value'
updated_at = <Date 2008-02-29.14:09:42.223>
user = 'https://bugs.python.org/kwatch'

bugs.python.org fields:

activity = <Date 2008-02-29.14:09:42.223>
actor = 'georg.brandl'
assignee = 'none'
closed = True
closed_date = <Date 2008-02-29.02:03:04.772>
closer = 'facundobatista'
components = ['Library (Lib)']
creation = <Date 2008-02-29.01:59:20.315>
creator = 'kwatch'
dependencies = []
files = ['9568']
hgrepos = []
issue_num = 2205
keywords = ['patch']
message_count = 4.0
messages = ['63116', '63117', '63118', '63137']
nosy_count = 3.0
nosy_names = ['georg.brandl', 'facundobatista', 'kwatch']
pr_nums = []
priority = 'normal'
resolution = 'rejected'
stage = None
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue2205'
versions = ['Python 2.5']

[facundobatista]

What?

Why you say that? What are you doing? What do you get? What do you
expect? In which version of Python and in which Platform are you working?

[kwatch]

I'm sorry to put empty submit.

os.time() returns incorrect value.

test.py:

    def f(n):
      if n <= 0:
          return 1
      else:
          return f(n-1) + f(n-2)
    
    import os
    t1 = os.times()
    f(34)
    t2 = os.times()
    
    utime = t2[0] - t1[0]
    stime = t2[1] - t1[1]
    total = utime + stime
    
    print "utime %.4f, stime %.4f, total %.4f" % (utime, stime, total)

result:

    $ time python bench.py
    utime 38.6333, stime 0.1000, total 38.7333
    
    real    0m23.787s
    user    0m23.211s
    sys     0m0.138s

This shows that real time is only 23.8 seconds, but os.times()
reports that user time is over 38 seconds.

This is due to bug of Modules/posixmodule.c.

Environment: python 2.5.2, MacOS X 10.4 Tiger, GCC 4.0

[kwatch]

See
http://groups.google.com/group/comp.lang.python/browse_thread/thread/8032897a30781df/c656a79d4c3268a6
for details about this bug.

[birkenfeld]

Isn't that tracked in bpo-1040026?