Very slow Cygwin startup on Windows 7

Dennis Hagarty (dehagart)
Tue Feb 24 15:29:00 GMT 2015


With Roger's very patient help, I was able to get ADInsight capturing information.

I did a run with the original dll under 32 bit Cygwin running a 32 bit program (echo).

Output and all possible reports (in html) from the tool are here: 

This 32 bit version is the original slower version (takes a few mins to open a window):
CYGWIN_NT-6.1-WOW DEHAGART-WS02 1.7.34(0.285/5/3) 2015-02-04 12:12 i686 Cygwin 

So I downloaded the snapshot DLL for 32 bits and did it again:
CYGWIN_NT-6.1-WOW DEHAGART-WS02 1.7.35s(0.286/5/3) 20150223 21:02:38 i686 Cygwin

But this time I wasn't able to get any output on the ADInsight (scratches head)
But the task runs within a second rather than the many minutes from the original version.

Thanks and Regards

-----Original Message-----
Hi Corinna,

Using x86_64/cygwin1-20150223.dll.xz??

~ uname -a
CYGWIN_NT-6.1 DEHAGART-WS02 1.7.35s(0.286/5/3) 20150223 21:02:38 x86_64 Cygwin

~ cat /etc/nsswitch.conf
passwd: db
group: db

First manual start of bash shell *seemed* to take slightly longer than before and slightly longer than files db setting.
But anyway, the timed results show this:

cmd /v:on /c "echo !TIME! & C:\cygwin64\bin\mintty.exe /bin/echo "test" & echo !TIME!"

C:\Users\dehagart>cmd /v:on /c "echo !TIME! & C:\cygwin64\bin\mintty.exe /bin/echo "test" & echo !TIME!"	
14:22:02.56	00:00.82
C:\Users\dehagart>cmd /v:on /c "echo !TIME! & C:\cygwin64\bin\mintty.exe /bin/echo "test" & echo !TIME!"	
14:22:07.27	00:00.17
C:\Users\dehagart>cmd /v:on /c "echo !TIME! & C:\cygwin64\bin\mintty.exe /bin/echo "test" & echo !TIME!"	
14:22:09.16	00:00.17
C:\Users\dehagart>cmd /v:on /c "echo !TIME! & C:\cygwin64\bin\mintty.exe /bin/echo "test" & echo !TIME!"	
14:22:10.89	00:00.17

I.e. significantly better.

-----Original Message-----

Hi Dennis,

On Feb 20 17:20, Corinna Vinschen wrote:
> On Feb 19 19:04, Dennis Hagarty (dehagart) wrote:
> > >It would be pretty helpful to get an idea what's so slow in your case.
> > >Either you get ADInsight working, or...  is it ok if I send you a link
> > >to a debug-augmented DLL via PM?
> > 
> > Sure.
> Thanks for helping debugging, Dennis.

I have another one for testing.  I rewrote the function fetching all the
group information for the groups in your user token, the one which is
mainly responsible for the 1.4 secs startup time.

In theory the performance improvement should be pretty noticable, even
with /etc/nsswitch.conf only using the "db" setting for groups.  In a
bigger environment with a user token of 150 groups, the time this
function took was reduced from ~300ms to ~50ms so I have high hopes.

Can you test this again with the Cygwin DLL from the latest developer
snaphshot at please? 


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

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