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Re: performance issue with sshd and cygrunsrv


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

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