[bind10-dev] Boss stopping msgq enhancements (#2249)

[JINMEI Tatuya / 神明達哉]

At Tue, 9 Oct 2012 19:45:40 +0200,
Michal 'vorner' Vaner <michal.vaner at nic.cz> wrote:
> 
> Hello
> 
> While I still believe it is a problem that xfrin did stay up so long, I
> promised I'd send an email about the ways I see for #2249. So here they are.

FWIW, I agree.  As an administrator when I explicitly shut down the
system I want it to complete as soon as possible.  I don't want to
wait for the possibly hanging xfr sessions.  But that's another
issue...

> Hiding the problem under the rug
> The ugly and fast way
> Semi-manual way
> Dependency tracking

> So, which one do we want to do?

In theory I'd like to have the concept of inter module(component)
dependency.  It will solve various issues, not only the shutdown
delay, in a clean way.  But I'm not sure if we can afford time for
designing and implementing it soon, either.

Depending on the seriousness of this particular issue, a reasonable
middleground would be the "semi-manual" way using the priorities.  As
an operational convention I guess we can simply give msgq the highest
priority, and allow others can shut down in parallel (or, even
complete sequential shutdown may be acceptable.  If each process dies
smoothly, it would take just a few (~5) seconds.  Maybe not ideal, but
I can live with that).

---
JINMEI, Tatuya
Internet Systems Consortium, Inc.