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Date: Sun, 22 Mar 2020 03:21:35 +0000
To: "cygwin@cygwin.com" <cygwin@cygwin.com>
From: Joe <joeworth@protonmail.com>
Reply-To: Joe <joeworth@protonmail.com>
Subject: New pty implementation is really slow
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I'm using cygwin 3.1.4 on Windows 10.

The new pseudo terminal stuff seems really slow.

For example:
$ time seq 10000
(output omitted)
real    0m23.510s
user    0m1.515s
sys     0m4.483s

If I minimize the mintty window while seq is running, it gets slightly bett=
er:
real    0m4.562s
user    0m0.390s
sys     0m1.202s

But when I set CYGWIN=3Ddisable_pcon before starting mintty, I get:
$ time seq 10000
(output omitted)
real    0m0.366s
user    0m0.109s
sys     0m0.093s

So the new implementation seems to be over 60 times slower than the old one=
.