[Samba] CTDB problems

[Martin Schwenke]

On Wed, 19 Apr 2017 18:14:38 +0200, David Disseldorp via samba
<samba at lists.samba.org> wrote:

> On Wed, 19 Apr 2017 18:06:35 +0200, David Disseldorp via samba wrote:
> 
> > > 2017/04/19 10:40:31.294250 [ 7423]: /etc/ctdb/debug_locks.sh: line 73: 
> > > gstack: command not found    
> > 
> > This script attempts to dump the stack trace of the blocked process,
> > but can't as gstack isn't installed - it should be available in the
> > gdb package.
> > 
> > @Martin: would the attached (untested) patch make sense?  
> 
> Gah, this time with the actual patch, instead of a Vim swap file.

A package dependency on gdb would probably be better.  :-)

When there have actually been deadlocks that needed to be understood
then we have needed gstack.  The kernel stack doesn't provide enough
useful information. The only time the kernel stack provides anything
useful is when a process is stuck in D state, gstack would hang, so we
get the kernel stack and see that the process is stuck in the cluster
filesystem.

So, without a package dependency, it is probably better for the admin
to get a clear indication that gstack is missing and should be installed,
even if it is somewhat clunky.

peace & happiness,
martin