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1.3.11: dramatic slowdown of compiled C code (Win 2000)


Sorry for my previous mail.  I did not read the gudelines before I sent it
(it was my first email to this list).

Here is my previous email:

I am not sure if you are aware of this, but the recent upgrade of the
Cygwin DLL (to version 1.3.11-3) caused a dramatic (3 to 7 fold) slowdown
of gcc compiled code.

The code is a preprocessor of large text files.  It essentially reads a
file (up to 1,500,000 lines) and writes a reformatted file (essentially the
same number of lines).  It seems like the slowdown occurs during file IO.
I am noticing 3-fold decrease on reads and 7-fold decrease on writes.

I routinely use the setup utility to keep my Cygwin environment up to date.
Is it safe to downgrade the cygwin module to 1.3.10 (I just downloaded the
cygwin-1.3.10-1.tar.bz2).

I investigated the problem a little further and the results are even more
dramatic.  I am almost sure that the problem is in cygwin1.dll.  Here is
what I did:

(1) I timed my code with 1.3.11-3 DLL - the results are: 80s the reading
part and 140s the writing part for the total of 220s.
(2) I replaced the cygwin1.dll ONLY with 1.3.10-1.  I re-ran the executable
without touching anything else!  The results: 7s reading 6s writing for a
total of 13s.

The difference is almost 17-fold!

I am running Cygwin environment on a IBM Intellistation with Windows 2000
Professional (SP 2).  I attaching the output of cygcheck -s -v -r.  I hope
that attachments can be handled by the discussion list server.

Andy

(See attached file: ccc.txt)

__________________________________
Andy Jaworski
Engineering Systems Technology Center
3M Center, 518-1-01
St. Paul, MN 55144-1000
-----
E-mail: apjaworski@mmm.com
Tel:  (651) 733-6092
Fax:  (651) 736-3122

Attachment: ccc.txt
Description: Binary data

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