On Sat, May 12, 2007 at 05:52:36PM +0400, Dmitry Koterov wrote:
> But please, detalize how Slony uses LISTEN/NOTIFY and why, if it uses
> LISTEN/NOTIFY, it still generates poll queries instead of sitting and
> waiting for a NOTIFY event. I cannot find this information in the Slony
> documentation.

Which version are you using?  In the past, we found that too much
reliance on LISTEN/NOTIFY tended to cause bloat in pg_listener and a
different set of problems.  So 1.2.x reduced that cost, at the
expense of additional polls.  Those polls should be cheap.  I'm
mostly worried about. . .

> possible without bombing the master by polling queries. E.g. lag 0.2s is
> allowed, but 5 polling queries per second is too much.

. . .this.  Why is it too much?  Anyway, if that's too much, then why
not set the lag to the level you'd find acceptable?

A

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Andrew Sullivan  | ajs at crankycanuck.ca
This work was visionary and imaginative, and goes to show that visionary
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