[postgis-users] Optimizer choosing slower strategy (Bitmap Heap vs Index)?

[Dan Lyke]

On Thu, 27 Jul 2017 09:33:03 +0200
Giuseppe Broccolo <g.broccolo.7 at gmail.com> wrote:
> Moreover, if RAM resource is enough to contain the data in memory,
> blocks distribution
> on disk should not be a problem (anyway, since we are talking about
> this, could you provide
> the ratio datasetsize/RAMresource?).

So over this weekend I exported the entire database out and imported it
into a new instance. Now that one table size is down to 34GB (from
70GB before), which seems more in-line with the earlier database version
(I guess something happened with extraneous data on import that got
deleted).

But the problem persists.

This main table is 34G, we've got 3 other tables we use intensively, one
is about 3.4G, the other two are 200M and 34M.

We're running this on Amazon db.m3.2xlarge instances, so 8vCPU with 30G
of RAM.

Dan