Instead of using slow sysconfig and loading the big _sysconfig_data dictionary in memory, would it be possible to extract the minimum set of sysconfig needed by the site module and put it in a builtin module? In site.py, I only found 4 variables:
from sysconfig import get_config_var
USER_BASE = get_config_var('userbase')
from sysconfig import get_path
USER_SITE = get_path('purelib', 'osx_framework_user')
USER_SITE = get_path('purelib', '%s_user' % os.name)
from sysconfig import get_config_var
framework = get_config_var("PYTHONFRAMEWORK")
Because of the site module, the _sysconfig_data module dictionary is always loaded in memory even for for a dummy print("Hello World!").
I suggest to start building a _site builtin module: subset of site.py which would avoid sysconfig and reimplement things in C for best performances.
speed.python.org:
* python_startup: 14 ms
* python_startup_nosite: 8 ms
Importing site takes 6 ms: 42% of 14 ms...
I'm interested to know if it would be possible to reduce these 6 ms by rewriting some parts of site.py in C.