I spent some more time playing with the PL/pgSQL-based workload. I find
that I'm still able to trigger the behavior if I:
a.) Drop the primary key column entirely from the table and the stored
procedure (basically, just perform read-then-insert on the single "key"
column).
b.) Change the "key" column from a varchar to an integer.
I started to wonder if this suggests an issue with page-level locking on a
non-indexed column. So, I recompiled PostgreSQL 9.3.5 with blocksizes of
32768 (./configure --with-blocksize=32) and 1024 and didn't have any
discernible effect (was able to reproduce). I also directly modified the
configure script to allow a 1MB blocksize and was again able to reproduce
the behavior.
Have you had any luck reproducing this behavior?
Thanks,
Peter
On Tue, Oct 21, 2014 at 11:28 AM, Kevin Grittner <kgrittn@ymail.com> wrote:
> Peter Bailis <pbailis@cs.berkeley.edu> wrote:
>
> > I just re-ran the workload with max_pred_locks_per_transaction set
> > (in postgresql.conf) to each of 1280, 12800, and 128000 and
> > observed the duplicate behavior under each setting.
> Thanks for checking!
>
> Looking into it....
>
> --
> Kevin Grittner
> EDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>
