Re: Global Sequences

On 16 October 2012 13:26, Markus Wanner <markus(at)bluegap(dot)ch> wrote:

> Why does a "Global Sequences" API necessarily hook at the nextval() and
> setval() level? That sounds like it yields an awkward amount of
> duplicate work. Reading this thread, so far it looks like we agree that
> option 3) is the most feasible optimization (the strict ordering being
> the un-optimized starting point). Do we really need an API that allows
> for implementations of options 1) and 2)?

Where else would you put the hook? The hook's location as described
won't change whether you decide you want 1, 2 or 3.

> What I'd appreciate more is a common implementation for option 3) with
> an API to plug in different solutions to the underlying consensus problem.

Implementations will be similar, differing mostly in the topology and
transport layer, which means its not going to be possible to provide
such a thing initially without slowing it down to the point we don't
actually get it at all.

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Simon Riggs http://www.2ndQuadrant.com/
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