[ClusterLabs] pcsd processes using 100% CPU

[Casey & Gina]

> gcore is part of gdb:
> https://packages.ubuntu.com/xenial/amd64/gdb/filelist
> 
> Note that using the utility should have no observable influence
> on the running process in question.

When I ran gcore on the pid, it produced a whole bunch of memory read errors like this:

warning: Memory read failed for corefile section, 8192 bytes at 0x93177000.
warning: Memory read failed for corefile section, 1048576 bytes at 0x93179000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93378000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93379000.
warning: Memory read failed for corefile section, 8192 bytes at 0x9337a000.
warning: Memory read failed for corefile section, 1048576 bytes at 0x9337c000.
warning: Memory read failed for corefile section, 4096 bytes at 0x9357c000.
warning: Memory read failed for corefile section, 4096 bytes at 0x9357d000.
warning: Memory read failed for corefile section, 8192 bytes at 0x9357e000.
warning: Memory read failed for corefile section, 1048576 bytes at 0x93580000.
warning: Memory read failed for corefile section, 4096 bytes at 0x9377f000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93780000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93982000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93983000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93fac000.
warning: Memory read failed for corefile section, 4096 bytes at 0x93fad000.
warning: Memory read failed for corefile section, 4096 bytes at 0x941b6000.
warning: Memory read failed for corefile section, 4096 bytes at 0x941b7000.
warning: Memory read failed for corefile section, 188416 bytes at 0x941b8000.
warning: Memory read failed for corefile section, 4096 bytes at 0x943e8000.
warning: Memory read failed for corefile section, 4096 bytes at 0x943e9000.
warning: Memory read failed for corefile section, 4096 bytes at 0x94668000.
warning: Memory read failed for corefile section, 4096 bytes at 0x94669000.

Nonetheless, it did produce a core file.

> load it to gdb (together with appropriate
> debug symbols) and from here, you can investigate further.

I'm sorry, but I don't really know how to do that.  Could you provide some instructions of what I should do?

I tried running `gdb --core=core.24923` but that threw errors:

Failed to read a valid object file image from memory.
Core was generated by `/usr/bin/ruby'.
Program terminated with signal SIGSTOP, Stopped (signal).
#0  0x000000000254a790 in ?? ()
[Current thread is 1 (LWP 24923)]

When I then looked at ps again, the process was no longer running, so I guess one of the above commands killed it.  So, I don't have a running process to work with anymore.

The core file is 1GB large!  It gzipped down to 5MB.  Would it be useful for me to send this to you to look at directly?

Thanks,
-- 
Casey