Re: random_page_cost = 2.0 on Heroku Postgres

Le vendredi 10 février 2012 20:32:50, Josh Berkus a écrit :
> On 2/9/12 2:41 PM, Peter van Hardenberg wrote:
> > Hmm, perhaps we could usefully aggregate auto_explain output.
>
> The other option is to take a statistical approach.  After all, what you
> want to do is optimize average response times across all your user's
> databases, not optimize for a few specific queries.
>
> So one thought would be to add in pg_stat_statements to your platform
> ... something I'd like to see Heroku do anyway.  Then you can sample
> this across dozens (or hundreds) of user databases, each with RPC set to
> a slightly different level, and aggregate it into a heat map.
>
> That's the way I'd do it, anyway.

in such set up, I sometime build a ratio between transactions processed and
CPU usage, many indicators exists, inside and outside DB, that are useful to
combine and use just as a 'this is normal behavior'. It turns to be easy in
the long term to see if things go better or worse.

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