possible grep V3.7 issue

[Eliot Moss]

On 6/6/2022 8:26 AM, Gordon Grimes via Cygwin wrote:
> Hi,
> 
> I wanted to let you know about a possible issue I found in grep v3.7.  I run Cygwin and recently downgraded ‘grep’ to v3.6 from v3.7 to address a performance issue (shown below).
> I just thought you’d want to know  (V3.6 is working well, so I’m in a good place 😊 )
> Enjoy,
> -g-
> 
> 
> % time echo hi | grep h
> hi
> 
> real        0m7.442s
> user       0m0.030s
> sys          0m6.576s
> 
> % /usr/bin/grep --version
> grep (GNU grep) 3.7
> Packaged by Cygwin (3.7-2)
> Copyright (C) 2021 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later https://gnu.org/licenses/gpl.html.
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.
> 
> Written by Mike Haertel and others; see
> https://git.sv.gnu.org/cgit/grep.git/tree/AUTHORS.
> 
> After the downgrade…
> 
> % time echo hi | grep h
> hi
> 
> real        0m0.292s
> user       0m0.015s
> sys          0m0.124s

I'm running 3.7-2 and get timing similar to what you give
for 3.6:

real    0m0.167s
user    0m0.015s
sys     0m0.061s

Not sure what to say unless, if I downgraded, it would be
an order of magnitude faster ...

I wonder if maybe the new version triggers some anti-virus
activity or something like that.

Eliot Moss