pybind11/tools/libsize.py
Jason Rhinelander dc0b4bd2c9 Add debugging info about .so size to build output (#477)
* Add debugging info about so size to build output

This adds a small python script to tools that captures before-and-after
.so sizes between builds and outputs this in the build output via a
string such as:

------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 924696 (decrease of 73680 bytes = 7.38%)

------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376 (increase of 73680 bytes = 7.97%)

------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376 (no change)

Or, if there was no .so during the build, just the .so size by itself:

------ pybind11_tests.cpython-35m-x86_64-linux-gnu.so file size: 998376

This allows you to, for example, build, checkout a different branch,
rebuild, and easily see exactly the change in the pybind11_tests.so
size.

It also allows looking at the travis and appveyor build logs to get an
idea of .so/.dll sizes across different build systems.

* Minor libsize.py script changes

- Use RAII open
- Remove unused libsize=-1
- Report change as [+-]xyz bytes = [+-]a.bc%
2016-11-04 14:47:41 +01:00

39 lines
1.1 KiB
Python

from __future__ import print_function
import os
import sys
# Internal build script for generating debugging test .so size.
# Usage:
# python libsize.py file.so save.txt -- displays the size of file.so and, if save.txt exists, compares it to the
# size in it, then overwrites save.txt with the new size for future runs.
if len(sys.argv) != 3:
sys.exit("Invalid arguments: usage: python libsize.py file.so save.txt")
lib = sys.argv[1]
save = sys.argv[2]
if not os.path.exists(lib):
sys.exit("Error: requested file ({}) does not exist".format(lib))
libsize = os.path.getsize(lib)
print("------", os.path.basename(lib), "file size:", libsize, end='')
if os.path.exists(save):
with open(save) as sf:
oldsize = int(sf.readline())
if oldsize > 0:
change = libsize - oldsize
if change == 0:
print(" (no change)")
else:
print(" (change of {:+} bytes = {:+.2%})".format(change, change / oldsize))
else:
print()
with open(save, 'w') as sf:
sf.write(str(libsize))