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

[Takashi Yano]

On Tue, 7 Sep 2021 11:14:28 +0200
Corinna Vinschen wrote:
> On Sep  7 08:39, Takashi Yano wrote:
> > On Mon, 6 Sep 2021 18:08:54 +0200
> > Corinna Vinschen wrote:
> > > On Sep  6 22:16, Takashi Yano wrote:
> > > > Current git head seems to have some bug. With and without my patch,
> > > > sftp get for large file causes error:
> > > > 
> > > > [yano@Express5800-S70 ~]$ sftp 192.168.0.133
> > > > yano@192.168.0.133's password:
> > > > Connected to 192.168.0.133.
> > > > sftp> get test.dat
> > > > Fetching /home/yano/test.dat to test.dat
> > > > test.dat                                       13%   66MB  66.4MB/s   00:06 ETAReceived message too long 1728053256
> > > > Ensure the remote shell produces no output for non-interactive sessions.
> > > > [yano@Express5800-S70 ~]$ sftp 192.168.0.133
> > > > yano@192.168.0.133's password:
> > > > Connected to 192.168.0.133.
> > > > sftp> get test.dat
> > > > Fetching /home/yano/test.dat to test.dat
> > > > test.dat                                       22%  111MB 110.6MB/s   00:03 ETAdo_download: parse: incomplete message
> > > > [yano@Express5800-S70 ~]$
> > > 
> > > I bisected this down to commit 296bd3e78b52, but I'm at a loss in
> > > terms of the cause of the problem, ATM.
> > 
> > Thanks for bisecting this.
> > 
> > I am not sure this is the correct thing, however, found the following
> > patch solves the issue.
> 
> Thanks for the patch!  It's not correct as such, because it enables
> SA_RESTART behaviour unconditionally, but it gave me the right hint.
> 
> The underlying problem is that in case of a signal, the CancelIo call
> was missing.  The signal was processed, but the IO was still ongoing
> and so data was read or written without the application's knowledge.
> 
> Actually we can always call CancelIo.  It doesn't break the information
> in the IO_STATUS_BLOCK if the IO was already finished.  It just sets
> io.Status to STATUS_CANCELLED and io.Information to the number of bytes
> processed if it really canceled the ongoing IO.
> 
> I pushed a matching patch.

I have confirmed that your patch solves the issue. Thanks!


-- 
Takashi Yano <takashi.yano@nifty.ne.jp>