potential instability in cygwin after my last checkin

Conrad Scott Conrad.Scott@dsl.pipex.com
Thu Aug 1 15:14:00 GMT 2002


"Christopher Faylor" <cgf@redhat.com> wrote:
> So, it's possible that my current implementation is actually
slower than
> the old one.  I'll check on that in the next couple of days.

I've just done some timings with a pair of test programs, where
the server echoes everything it's sent and the client repeatedly
sends packets and waits for replies.  They also do a select before
each read from the socket (I've got a problem with selects for
writing so that's not in the test program as yet).

Anyhow, timings (done with bash's time command, averages over 3
runs):

Before Chris's changes:

real    29.9 seconds
user    1.8 seconds
system  6.75 seconds

After the changes:

real    23.4
user    1.3
system  4.88

which is a nice 20% improvement, not slower at all.

Just for comparison, the same test w/o any selects:

real    1.1
user    0.15
system  0.30

so there's still some room for improvement :-)

Of course, the other point here is that the code seems to work
fine (I'm also running XEmacs w/ gnuserv and CVS too).

// Conrad

p.s. I've been assuming that bash's time command returns sensible
values for the user and system times: they look plausible.  Are
they known to be good?





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