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

Takashi Yano
Mon Sep 13 18:39:51 GMT 2021

On Mon, 13 Sep 2021 09:03:04 -0400
Ken Brown wrote:
> On 9/13/2021 5:42 AM, Corinna Vinschen wrote:
> > Didn't we also have a problem with C# in terms of non-blocking pipes?
> > I wonder if we could just do the following: As soon as we spawn a
> > non-Cygwin process, just call set_pipe_non_blocking(false) for all
> > pipes.  Blocking vs. nonblocking mode is a per-handle thingy anyway.
> > 
> > What do you think?
> I don't remember exactly what the issue was with C# programs, so I'll defer to 
> Takashi on this.

Actually, piping C# program has a problem even if setting the pipe
blocking. It needs also pipe_byte and FILE_SYNCHRONOUS_IO_NONALERT.
However, I agree it is safer to set the pipe blocking for non-cygwin

Takashi Yano <>

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