Re: Squid AsyncIO and LinuxThread

Apiset Tananchai wrote:

> Sorry for my misleading, but I still can't seem to find a core file
> anywhere.

Right. Linux does NOT produce a core from a threaded app.

> Is someone running squid on Linux has some suggestion? At first,
> I think it was because the use of LinuxThread but maybe it not
> the case.

Debugging threaded Linux apps is a pain at the moment. Work is being
made at gdb to improve the situation. But since Squid mostly faults in
the main thread is it not such a big pain. What you need to do is to run
Squid from gdb.

If your cache is a production machine then adding a automated stack
trace may help you (I assume that you do not like to manually restart it
if it crashes on a production machine).
1. Create a modified RunCache that starts "gdb squid" with no options
instead of "squid -sY"
2. Create a .gdbinit file in the directory from where you start
RunCache, containing the following lines (without linenumber:)
   1: handle SIGUSR1 nostop noprint
   2: handle SIGUSR2 nostop noprint
   3: r -CsY
   4: bt
   5: quit
3. Start Squid using your modified RunCache..
4. Stack traces should be seen in squid.out (assuming you kept the
redirection from original RunCache script)

---
Henrik Nordström
Sparetime Squid Hacker