cygrunsrv + sshd + rsync = 20 times too slow -- throttled?

[Corinna Vinschen]

On Aug 30 11:00, Ken Brown wrote:
> On 8/30/2021 9:51 AM, Ken Brown wrote:
> > On 8/30/2021 8:55 AM, Corinna Vinschen wrote:
> > > On Aug 30 21:04, Takashi Yano wrote:
> > > No worries.  The same should apply to the NtCreateFile side of the
> > > pipe, btw.
> > 
> > I'll add my thanks.  I should have checked the default flags that are
> > typically used for other devices when I wrote nt_create.  I'm glad you
> > caught this.
> > 
> > So I'll reinstate the use of nt_create and then let Takashi recheck everything.
> 
> I've done this now.  I'm still not sure I've got all the flags right.  For
> unknown reasons, I've used FILE_SHARE_READ | FILE_SHARE_WRITE in the call to
> NtCreateNamedPipeFile, and no sharing in the call to NtOpenFile.  Should I
> also use FILE_SHARE_READ | FILE_SHARE in NtOpenFile?  Is sharing even
> relevant in this context?

This is only relevant if you want to open the pipe from another context,
calling CreateNamedPipe/CreateFile.  As long as the pipe is only
duplicated, it shouldn't matter at all.

But, as I just wrote in my previous mail, the FILE_SYNCHRONOUS_IO_NONALERT
flag is probably a good thing for C# apps, but not for Cygwin, because it
enforces synchronous operation.  Sorry about that...


Corinna