Re: infinite loop in parallel hash joins / DSA / get_best_segment

From: Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com>
To: Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>
Cc: Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: infinite loop in parallel hash joins / DSA / get_best_segment
Date: 2018-09-17 23:35:25
Message-ID: CAEepm=3Bo0WCXmuyacSR6Oc90rPOe6Vop7_o07p4g9Mf5U0q7w@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Mon, Sep 17, 2018 at 9:12 PM Thomas Munro
<thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> On Mon, Sep 17, 2018 at 10:42 AM Thomas Munro
> <thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> > On Mon, Sep 17, 2018 at 10:38 AM Tomas Vondra
> > <tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:
> > > While performing some benchmarks on REL_11_STABLE (at 444455c2d9), I've
> > > repeatedly hit an apparent infinite loop on TPC-H query 4. I don't know
> > > what exactly are the triggering conditions, but the symptoms are these:
> > >
> > > ...
>
> With the attached draft patch, Tomas's benchmark script runs happily
> for long periods. A bit more study required with fresh eyes,
> tomorrow.

Here is a tidied up version that I propose to back-patch to 10 & 11.

--
Thomas Munro
http://www.enterprisedb.com

Attachment Content-Type Size
0001-Fix-segment_bins-corruption-in-dsa.c.patch application/octet-stream 5.1 KB

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2018-09-17 23:38:24 Re: pgsql: Allow concurrent-safe open() and fopen() in frontend code for Wi
Previous Message Stephen Frost 2018-09-17 22:01:33 Re: Online verification of checksums