Michael B Allen wrote:
On Fri, Oct 16, 2009 at 1:10 PM, Joe Lewis <j...@joe-lewis.com> wrote:
Michael B Allen wrote:
I have a customer who very occasionally sees apache workers hang. I'm
pretty sure this is caused by an errant module but I don't know which
one.
Is there any way to determine which module is causing Apache workers to
hang?
Can I temporarily disable that SIGTERM so that I can have enough time
to attach GDB to the hanging processes?
Mike
Perhaps run it in a non-forking mode (httpd -X -k start) inside of gdb and
see what it hangs on?
If I run it in gdb like you suggest:
# gdb httpd
(gdb) run -X -k start
I cannot get httpd to run module deinitialization. Meaning if I do
apachectl stop or httpd -X -k stop or graceful-stop in another
terminal, it just kills the whole process group. Since the problem is
hanging during module deinitialization I don't think this is going to
help me. How do I shutdown httpd so that it runs the module
deinitialization routines?
Otherwise does anyone have a web-svn pointer to the code that's
calling the SIGTERM? Maybe I can find a way to disable it.
Mike
Disabling SIGTERM for apache would be akin to leaving the landing gear
of your airplane on the ground when you take off. How are you going to
properly shutdown apache if you completely kill the SIGTERM signals?
The "deinitialization" - are you just not seeing the messages you'd
normally see? Or did apache just terminate (which is normal in gdb,
which causes the gdb session to terminate as well).
Two possibilities - gdb and attach to a currently running child (and
hope you get lucky), or strace the processes.
--
Joe Lewis
Chief Nerd SILVERHAWK <http://www.silverhawk.net/>
------------------------------------------------------------------------
/The folly of intelligent people, clear-headed and narrow-visioned, has
precipitated many catastrophies.
--Alfred North Whitehead/
