25 Jul 2013, 16:19
Dmfcb_pragsmall

David Copeland (98 posts)

In Chapter 16 we create a sub-supervisor to manage the sequence server. The book merely states that we have to do this, but not why.

So, why do I need to do this? Why not just have the main supervisor supervise both the Stash and the Sequence.Server?

02 Aug 2013, 14:19
Dave_gnome_head_isolated_pragsmall

Dave Thomas (337 posts)

What happens if it crashes? We lose the stash

02 Aug 2013, 19:45
Dmfcb_pragsmall

David Copeland (98 posts)

Wait, so if the Sequence.Server crashes, its supervisor crashes, too?

05 Aug 2013, 12:50
Dmfcb_pragsmall

David Copeland (98 posts)

I re-worked the sequence server to not use a sub-supervisor for the Sequence.Server - both the stash and the sequence server are supervised by the same supervisor. Crashing the Sequence.Server has no effect on the stash. The Sequence.Server comes back to life and the stash is persisted.

So, I’m just not understanding why we need a sub supervisor

08 Aug 2013, 19:12
Dave_gnome_head_isolated_pragsmall

Dave Thomas (337 posts)

Because the policies for the two levels are different (or most likely are). The actual sequence servers can be transient—they can crash and no one cares. But the stash should be protected. So I split them into separate supervisors, which isolates them better.

  You must be logged in to comment