On Thursday 05 October 2006 15:44, Charles Ulrich wrote: > Greetings, > > We have been running FreeBSD on our mail servers for about as long as I can > remember. Recently, we decided to go SMP to handle increased mail load. After > assembling the hardware, installing the OS and software, and restoring all of > our data, we noticed in testing that our first machine began hanging > semi-regularly when it began processing lots of mail. Disabling SMP > eliminated the hangs completely. We tried it all again on completely > different hardware with exactly the same result. Our conclusion: somethings's > buggy in SMP. > > Here are the symptoms. The machine hangs, and becomes completely > unresponsive. It looks like a deadlock. It will sometimes respond to the > power button and shut down (without being able to first sync and unmount > filesystems), and sometimes the power button event gets caught in the > deadlock. Sinceit's not actually a crash, there is no core dump or other > debugging information. In the most recent situation, it hung at different > points every time I tried to compile ezm3, after successfully compiling other > packages. > > We're system administrators, not kernel hackers, so this is a plea for help. > I > wouldn't know where to start, but I'm hoping someone can point me in the > right direction. We're also willing to give a (trustworthy) FreeBSD developer > root access to the test machine since it's just sitting idle right now. If > you need to crash it, that's fine. We'll have people during normal business > hours who know how to push a reset button. > > Thanks for your time.
Compile a debug kernel and include 'DDB' in the kernel. When it hangs, break into the debugger and type 'panic' to have it panic the machine and write out a crash dump. Once you have the crash dump, download http://www.FreeBSD.org/~jhb/gdb/gdb6 and do this: $ kgdb /usr/obj/usr/src/sys/FOO/kernel.debug /var/crash/vmcore.X (where FOO is your kernel config file and X is the right vmcore file) Then do this: (gdb) source /path/to/gdb6 (gdb) ps ... And reply with the output from the 'ps' command. -- John Baldwin _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-smp To unsubscribe, send any mail to "[EMAIL PROTECTED]"
