This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Slow performance Win7/64


On 2011-07-27 ìí 8:30, Heiko Elger wrote:
So the question is:

Is it a known problem?
Is it really OS (Win7) specific?
i'm not win7/64 user but i can count same timestamp per seconds as 17.
and attached file is gprof result when executed your testcase. (but not same dll from above. it has 2.42(17/7)x slowdown. so you would need to consider slowdown factor. from now i assume you are considering slowdown factor)
and as we can see, the waitpid takes about 140ms and in gprof report of date.exe, you can see sig_{dispatch_pending,send} consumes almost third quarter time.
actually, the unwoken wait_sig thread(because sigproc_init is called during DLL_PROCESS_ATTACH of dll_entry) is waken by sig_dispatch_pending call.
the problem is, it takes about 10ms to wake wait_sig thread in my pc.(surely main thread does nothing) and gprof report it has slowdown indeed.
so i think this is known problem, and it would be not only win7 specific problem. as we can confirm there is delay to wake wait_sig thread. although i can't make sure it is dominating factor.

Why is this problem not solved - cause it is to difficult to find? Yes I know it's open source and I'm a programmer too - but I'm realy not a programmer having the knowledge of Cygwin internal details.

Is there a workaround for that problem?
Any hints are welcome.

Attachment: gmon.sh.exe.1188.out_child.txt
Description: Text document

Attachment: gmon.sh.exe.2068.out_parent.txt
Description: Text document

Attachment: gmon.date.exe.4060.out.txt
Description: Text document

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]