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Hi Gregory, Hmm, would you really dislike it if we do an explicit kill() after closing the pipe? Andy On Mon, 27 Sep 2004, Gregory J. Sharp wrote: > Folks, > > The etc/XrdOlbMonPerf script in the xrootd distribution is generating > lots of orphan netstat -c -i 60 processes on our RHEL 3 system. > > I noticed that the pipe used to open the netstat isn't explicitly > closed, but presumably it is closed when XrdOlbMonPerf exits. At the > end of the while loop (~line 207) it would be cleaner to put > close(CMDFD); > but not essential, since it doesn't help the problem I have. > > It turns out that netstat doesn't die when the pipe it is writing to is > closed. It apparently keeps trying for up to 15-16 more iterations - > which means that each netstat hangs around for an extra 15 minutes if > you have a 60 second delay between iterations. It should exit if it > gets EPIPE while attempting to write its output. (You can try this with > "netstat -c -i 2 | cat; date" and then in another window figure out the > PID of cat and run "kill $CATPID; date" - it takes quite a while for > the netstat to die, and time is apparently proportional to the time > interval given to netstat.) > > I don't know if there is a simple cure for this. Putting in code to > make sure the netstat is dead seems like an unpleasant way to work > around a bug/misfeature in netstat on RHEL 3. > > -- > Gregory J. Sharp email: [log in to unmask] > Wilson Synchrotron Laboratory url: > http://www.lepp.cornell.edu/~gregor > Dryden Rd ph: +1 607 255 4882 > Ithaca, NY 14853 fax: +1 607 255 8062 > >