-Re: Opinions on the 'watcher' script that surrounds launched hbase daemons
Nick Dimiduk 2013-06-24, 23:13
The template approach is cleaner. It sounds like it's encroaching on BigTop
On Mon, Jun 24, 2013 at 1:49 PM, Stack <[EMAIL PROTECTED]> wrote:
> New in 0.95, when you do a process listing, there are two 'hbase'
> processes. There is the old java process itself and then there is the
> launcher script that is just hanging around waiting on the java process to
> exit so it can clear the process's znode. Clearing the znode will mean the
> master will know sooner of the missing regionserver. Otherwise it would
> have to wait wait on the melting of the ephemeral znode (tens of seconds).
> This 'watcher' was added by:
> HBASE-5844 Delete the region servers znode after a regions server crash
> What do folks think about how this facility has been implemented. I am not
> questioning the merit of fast-clear of the znode. This is a good idea. I
> just want to talk about how it is done. I am not a fan . Our little
> wrapper script verges into the process supervision space . Rather than
> do up our own, instead should we ship templates for a few common
> supervisors and undo our custom one?
> 2. http://en.wikipedia.org/wiki/Process_supervision