Re: PATCH: Split stats file per database WAS: autovacuum stress-testing our system

Tomas Vondra wrote:

> I've been thinking about this (actually I had a really weird dream about
> it this night) and I think it might work like this:
>
> (1) check the timestamp of the global file -> if it's too old, we need
> to send an inquiry or wait a bit longer
>
> (2) if it's new enough, we need to read it a look for that particular
> database - if it's not found, we have no info about it yet (this is
> the case handled by the dummy files)
>
> (3) if there's a database stat entry, we need to check the timestamp
> when it was written for the last time -> if it's too old, send an
> inquiry and wait a bit longer
>
> (4) well, we have a recent global file, it contains the database stat
> entry and it's fresh enough -> tadaaaaaa, we're done

Hmm, yes, I think this is what I was imagining. I had even considered
that the timestamp would be removed from the per-db file as you suggest
here.

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Álvaro Herrera http://www.2ndQuadrant.com/
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