Bootstrap scheme for Go port

Gustavo Niemeyer gustavo.niemeyer at
Mon Apr 23 12:51:32 UTC 2012

On Mon, Apr 23, 2012 at 03:53, Kapil Thangavelu
<kapil.thangavelu at> wrote:
> Looks great, we need this. Two comments though, since the version is
> effectively the same through the cluster (minus errors) what do we gain by not
> just using a single integer ala charms, ie. even minor version code drift is
> potentially problematic.

Please run through the list of goals and the implementation proposal
and try to apply the same logic with a single integer. You'll probably
figure why it won't cut. If not, please drop a mail again and we can
run through it.

> Second, the upgrade protocol for agents and schema
> migration capability is unspecified.

Yeah, we need more details for both, in their own spec/thread.
Upgrading agents in minor releases is simple: download new version,
unpack, and restart with it. No one should notice this has happened.

The schema migration will need more careful thinking as it will need
waiting barriers, watching the waiting barriers until all are ready,
and signaling to release them. We'll not be doing that for quite a
while, so I'd rather not jump into details right now, and focus on the
bits of the problem we need solutions for sooner.

Gustavo Niemeyer

-- I'm not absolutely sure of anything.

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