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

Dan Lyke danlyke at flutterby.com
Mon Jul 31 09:29:15 PDT 2017

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

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.


More information about the postgis-users mailing list