Re: Delay locking partitions during query execution

On Sat, 5 Jan 2019 at 03:12, Tomas Vondra  wrote:
> >>
> >>     partitions    0      100     1000    10000
> >>     --------------------------------------------
> >>     master       19     1590     2090      128
> >>     patched      18     1780     6820     1130
> >>
> >> So, that's nice. I wonder why the throughput drops so fast between 1k
> >> and 10k partitions, but I'll look into that later.
> >
> > Those look strange. Why is it so slow with the non-partitioned case?
> > I'd have expected that to be the fastest result.
> >
>
> Because there are 1M rows in the table, and it's doing a seqscan.

Of course. My test did the same, but I didn't consider that because I
had so few rows per partition.  Likely just adding an index would have
it make more sense.


-- 
 David Rowley                   http://www.2ndQuadrant.com/
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