performance issue with sshd and cygrunsrv

[Larry Hall (Cygwin)]

Stephen David wrote:
> Hello again,
> 
>>> Hello,
>>>
>>> I recently installed cygwin on a new windows 2003 server box, and am
>>> experiencing 100% CPU utilization for several seconds (approx 7) when
>>> running many commands via ssh connection *to* that box -- even simple
>>> commands like "ls -l", "find", that usually return immediately.
>>> 
>>> What's more interesting is when I run sshd in a command window
>>> (either  with -d or not) on the server, instead of via service control
>>> manager/cygrunsrv, the problem goes away. I've tried reverting back to the
>>> previous cygrunsrv version (1.18), with no change in behavior. I've also
>>> experimented with various settings in the sshd service (ntsec, etc).

I hope/assume that when you ran in the console you ran from a shell owned
by the user running the service.  If not, it's not a fair test and could
have messed up permissions on files and directories that the
service-oriented sshd needs.

>>> I also suspected that it might only involve commands that interact
>>> heavily with the filesystem, but even trying to run "vi" with a small file
>>> or no file at all produces the same result.
>>> 
>>> I saw in the list archives some suggestion about anti-virus/firewall
>>> software causing problems when forking processes, but i don't have any
>>> installed on this machine at the moment.
>>> 
>>> Any thoughts on where I should turn next to troubleshoot?
>>> 
>>> I've attached 'cygcheck -s -v -r' output.
> 
> With regard to this performance problem, I've discovered that this is not
> just an sshd problem -- scripts/commands I run through cron also exhibit the
> same behavior. (ie. find, curl, date, etc). Is there something about the
> user context under which these services run that could be causing this? Or
> does this point to cygrunsrv?
> 
> I should note this is a multi-processor machine (2 dual-core CPUs) -- not
> sure if there could be any issues there.
> 
> re-attached cygcheck output for reference.

Try creating a local service account (sshd_server) rather than a domain
one.  That would be more typical and could explain the difference.

-- 
Larry Hall                              http://www.rfk.com
RFK Partners, Inc.                      (508) 893-9779 - RFK Office
216 Dalton Rd.                          (508) 893-9889 - FAX
Holliston, MA 01746

_____________________________________________________________________

A: Yes.
 > Q: Are you sure?
 >> A: Because it reverses the logical flow of conversation.
 >>> Q: Why is top posting annoying in email?

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