At 10:48 PM 11/5/2002, CBFalconer wrote: >I have been using Cygwin to check portability, and recently tried >an experiment. I compiled and run the same, largely compute >bound, program on both systems and timed their execution. Both >were compiled with "gcc -W -Wall -O2 -ansi -pedantic -gstabs+", >using gcc 3.1 on DJGPP, and gcc 3.2 on Cygwin. Both on the >identical machine, running W98. > >The program was considerably slower on Cygwin. The execution >commands were: > >timerun a 30000 >timerun a 10000 on DJGPP, using 4dos command processor > (timerun is an alias, involving timer command) > >time ./a 30000 >time ./a 10000 on Cygwin, using bash 2.05 > >I believe the majority of the Cygwin slowdown is due to the slower >loading (although the program is much smaller than under DJGPP) >and slower console output handling. This is based on the >difference in times between the shorter and longer runs. > >FYI the test program was:
<snip> General performance with Cygwin is a known issue. At least some portion of this is the expected price you pay for POSIX compatibility. A better test would be to compare DJGPP with mingw (or even Cygwin gcc with -mno-cygwin). Still, I don't think anyone here will be very surprised to hear that Cygwin versions of the same programs run slower. If you're curious, there's more discussion of this in the email archives. Some of the performance issues will be addressed over time. Some you'll just have to live with. If you're inclined to track down the performance issues you see and offer possible solutions, I know the list would be very interested in your results. Larry Hall [EMAIL PROTECTED] RFK Partners, Inc. http://www.rfk.com 838 Washington Street (508) 893-9779 - RFK Office Holliston, MA 01746 (508) 893-9889 - FAX -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
