Re: [Python-Dev] Possible performance regression

2019年2月25日 01:26:05 -0800

> On Feb 24, 2019, at 10:06 PM, Eric Snow <[email protected]> wrote:
> 
> I'll look into it in more depth tomorrow. FWIW, I have a few commits
> in the range you described, so I want to make sure I didn't slow
> things down for us. :)
Thanks for looking into it.
FWIW, I can consistently reproduce the results several times in row. Here's 
the bash script I'm using:
#!/bin/bash
make clean
./configure
make # Apple LLVM 
version 10.0.0 (clang-10001145.5)
for i in `seq 1 3`;
do
 git checkout d610116a2e48b55788b62e11f2e6956af06b3de0 # Go back to 2/23
 make # Rebuild
 sleep 30 # Let the system 
get quiet and cool
 echo '---- baseline ---' >> results.txt # Label output
 ./python.exe Tools/scripts/var_access_benchmark.py >> results.txt # Run 
benchmark
 git checkout 16323cb2c3d315e02637cebebdc5ff46be32ecdf # Go to end-of-day 
2/24
 make # Rebuild
 sleep 30 # Let the system 
get quiet and cool
 echo '---- end of day ---' >> results.txt # Label output
 ./python.exe Tools/scripts/var_access_benchmark.py >> results.txt # Run 
benchmark
> 
> -eric
> 
> 
> * commit 175421b58cc97a2555e474f479f30a6c5d2250b0 (HEAD)
> | Author: Pablo Galindo <[email protected]>
> | Date: Sat Feb 23 03:02:06 2019 +0000
> |
> | bpo-36016: Add generation option to gc.getobjects() (GH-11909)
> 
> $ ./python Tools/scripts/var_access_benchmark.py
> Variable and attribute read access:
> 18.1 ns read_local
> 19.4 ns read_nonlocal
These timings are several times larger than they should be. Perhaps you're 
running a debug build? Or perhaps 32-bit? Or on VM or some such. Something 
looks way off because I'm getting 4 and 5 ns on my 2013 Haswell laptop.
Raymond
_______________________________________________
Python-Dev mailing list
[email protected]
https://mail.python.org/mailman/listinfo/python-dev
Unsubscribe: 
https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com

Reply via email to