Re: [wsrf] Scheduled termination, heartbeats and dependent objects

[Tom Maguire <tmaguire@us.ibm.com>]

inlined below


David Hull <dmh@tibco.com> wrote on 09/08/2004 05:47:20 PM:

> I dithered over this.  We definitely want to be able to use the
> death of a remote process as a signal to destroy resources
> associated with it.

I am much less definitive...

>
> I believe this is correct, if by "server" you mean "the thing
> managing the resource".  But it reverses the usual meaning of server
> w.r.t heartbeating, where the server is the process sending out
> heartbeats so that clients can tell it's alive.

"Server" is a term you used...

> In any case, I maintain there's something to be captured here.  For
> my money, though, the bigger win is with dependent objects.  You
> don't want either a separate lease or a separate stream of
> heartbeats for each child resource if you can help it.

I believe that heartbeating is an important construct however I am unsure
if heartbeating is in scope for the work of WSRF.  I would expect that
heartbeating would more properly be part of a "grouping" semantic
of highly available systems.  Further, I would expect that the heartbeat
would be multicast to other members of the group.  The creation of the
group would involve "voting", "joining" and "leaving".  In this context
a strong requirement of grouping would be reliable and ordered messages.

Tom