Re: multicolumn index and setting effective_cache_size using human-readable-numbers

On 29 February 2016 at 14:07, Geoff Winkless <pgsqladmin@geoff.dj> wrote:
> On 29 February 2016 at 14:06, Jim Mlodgenski <jimmy76@gmail.com> wrote:
>> No they are not the same. When you don't include a unit for
>> effective_cache_size, it defaults to page size so you're saying 2146435072 *
>> 8K
>
> Hah.
>
> Thanks Jim, like I said I was sure I'd be missing something :)

So ignoring my effective_cache_size vs units stupidity, and coming
back to the problem I was originally going to email about before I got
sidetracked...

Is there a reason why the single-column index is used when
effective_cache_size is so much lower, even though the index sizes are
not much different (2.3GB vs 3.2GB)? I can increase
effective_cache_size from (the current) 3GB up to 8GB before it starts
using the multicolumn index, which seems excessive given the relative
index sizes.

Geoff