PEP 418: Add link to benchmarking programs used to fill tables

This commit is contained in:
Victor Stinner 2012-04-19 01:28:22 +02:00
parent 636c74aeca
commit e1d068556d
1 changed files with 24 additions and 8 deletions

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@ -800,7 +800,9 @@ Performance
Reading an hardware clock has a cost. The following table compares
the performance of different hardware clocks on Linux 3.3 with Intel
Core i7-2600 at 3.40GHz (8 cores).
Core i7-2600 at 3.40GHz (8 cores). The `bench_time.c
<http://hg.python.org/peps/file/tip/pep-0418/bench_time.c>`_ program
was used to fill these tables.
======================== ====== ======= ======
Function TSC ACPI PM HPET
@ -817,10 +819,6 @@ CLOCK_REALTIME 27 ns 707 ns 629 ns
CLOCK_MONOTONIC 27 ns 723 ns 635 ns
======================== ====== ======= ======
Each function was called 10,000,000 times and CLOCK_MONOTONIC was used
to get the time before and after. The benchmark was run 5 times to
keep the minimum time.
FreeBSD 8.0 in kvm with hardware virtualization:
======================== ====== ========= ======= =======
@ -918,6 +916,11 @@ CLOCK_MONOTONIC_COARSE Linux 3.0 4 ms 4 ms
GetTickCount64() Windows Seven 16 ms 15 ms
========================= ================ ========= ===================
The "Precision in Python" column was filled using the
`clock_precision.py
<http://hg.python.org/peps/file/tip/pep-0418/clock_precision.py>`_
program.
mach_absolute_time
^^^^^^^^^^^^^^^^^^
@ -1165,6 +1168,11 @@ GetSystemTimeAsFileTime() Windows Seven 16 ms 1 ms
ftime() Windows Seven \- 1 ms
========================= ================ ========= ===================
The "Precision in Python" column was filled using the
`clock_precision.py
<http://hg.python.org/peps/file/tip/pep-0418/clock_precision.py>`_
program.
Windows: GetSystemTimeAsFileTime
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -1240,6 +1248,11 @@ GetProcessTimes() Windows Seven 16 ms 16 ms
clock() Windows Seven 1 ms 1 ms
========================= ================ ========= ===================
The "Precision in Python" column was filled using the
`clock_precision.py
<http://hg.python.org/peps/file/tip/pep-0418/clock_precision.py>`_
program.
Functions
^^^^^^^^^
@ -1294,8 +1307,10 @@ CLOCK_THREAD_CPUTIME_ID Linux 3.3 1 ns 649 n
GetThreadTimes() Windows Seven 16 ms 16 ms
========================= ================ =============== ===================
CLOCK_THREAD_CPUTIME_ID returns a number of CPU cycles, not a number of
seconds.
The "Precision in Python" column was filled using the
`clock_precision.py
<http://hg.python.org/peps/file/tip/pep-0418/clock_precision.py>`_
program.
Functions
@ -1305,7 +1320,8 @@ Functions
<http://msdn.microsoft.com/en-us/library/windows/desktop/ms683237(v=vs.85).aspx>`_.
The precision can be read using GetSystemTimeAdjustment().
* clock_gettime(CLOCK_THREAD_CPUTIME_ID): Thread-specific CPU-time
clock. The precision can be read using of clock_getres().
clock. It uses a number of CPU cycles, not a number of seconds.
The precision can be read using of clock_getres().
See also the `QueryThreadCycleTime() function
<http://msdn.microsoft.com/en-us/library/windows/desktop/ms684943(v=vs.85).aspx>`_