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Re: very poor cygwin scp performance in some situations

Interesting idea that I just tried setting high prio on the command line
version and it does benefit obtaining 6.0MB/s but not quite matching
the 6.2MB/s of the daemonised version.
Note: Using realtime prio drops the rate back to 4.3MB/s

Oh just tried using above normal and that hits 6.2MB/s so that looks
like its the reason but why just removing -D should produce the
same effects is beyond me.

Max rate seen is now straight /usr/sbin/ssh using above normal prio
notching up 6.4MB/s not that its much difference as +-1second
makes the difference. Interesting neither the less.

----- Original Message ----- From: "René Berber"
Also very interesting is when running sshd from the command line with
/usr/sbin/sshd -D vs running it via cygrunsvr I get:
* cmdline = 192MB   4.4MB/s   00:44
* cygrunsvr = 192MB   6.4MB/s   00:30
* cmdline without -D = 192MB   6.4MB/s   00:30

I tried running:
/usr/sbin/sshd -D 2>&1 > /dev/null but no difference from the standard
so the difference might be the closed stdin which would support select
being at least a contributing factor?

Changing performance options (in System Properties -> Advanced -> Performance Options -> Advanced) to give services preference may have the same impact.

If it does, that means that the sshd process just needs a higher priority to
give better performance (sounds too obvious) at other processes expense.

Your results are interesting.

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