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Date: Thu, 11 Apr 2019 16:16:49 +0300
From: Alexander Zagrebin <alex@zagrebin.ru>
To: ports@freebsd.org
Subject: python 3 subprocess performance
Message-ID: <20190411161649.1b740d21@vm2.home.zagrebin.ru>
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Hi!

I've noticed the subprocess performance issue with python 3.
For example, this simple script takes just 0,15 second to complete
with python 2.7, but more than 5 sec with python 3.6:

import subprocess

for i in range(100):
    p = subprocess.Popen(['uname', '-a'], stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    (stdoutdata, stderrdata) = p.communicate()

Profiling with the cProfile shows, that this excessive 5 seconds was
wasted in the "{built-in method posix.read}"

Could anybody confirm this issue?

-- 
Alexander Zagrebin