From: Heikki Linnakangas <hlinnaka@iki.fi>
To: Peter Geoghegan <pg@heroku.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Jeff Janes <jeff.janes@gmail.com>
Cc: Stephen Frost <sfrost@snowman.net>
Cc: Dean Rasheed <dean.a.rasheed@gmail.com>
Cc: Bruce Momjian <bruce@momjian.us>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: INSERT ... ON CONFLICT UPDATE/IGNORE 4.0
Date: Fri, 01 May 2015 07:47:48 -0700
Message-ID: <55439214.6080506@iki.fi> (raw)
In-Reply-To: <CAM3SWZQ3TzqC13FtH5D1kC6iJ8N_=yrKwg4PCwDcy_ZiQ2FDoA@mail.gmail.com>
References: <CAM3SWZTGE0z5_E8wRi9wt3qgOiMpSwtwr5uDcZDGhRZ1_pz6vg@mail.gmail.com>
<CAM3SWZTzKXsGkxDdxNZjJEm=3P0Eq63y8OUV5rD5cegoWK8B_A@mail.gmail.com>
<553EFF0D.4040903@iki.fi>
<CAM3SWZR9RNzQS7prmU0mt4mZ8CQ7f4+UP-vvbT87y8CT_SLFxQ@mail.gmail.com>
<5542DE23.6060800@iki.fi>
<CAM3SWZQ3TzqC13FtH5D1kC6iJ8N_=yrKwg4PCwDcy_ZiQ2FDoA@mail.gmail.com>
List-Unsubscribe: <mailto:majordomo@postgresql.org?body=unsub%20pgsql-hackers>
On 04/30/2015 11:09 PM, Peter Geoghegan wrote:
> I've been unable to reproduce the unprincipled deadlock using the same
> test case as before. However, the exclusion constraint code now
> livelocks. Here is example output from a stress-testing session:
>
>...
>
> [Fri May 1 04:45:35 2015] normal exit at 1430455535 after 128000
> items processed at count_upsert_exclusion.pl line 192.
> trying 128 clients:
> [Fri May 1 04:45:58 2015] NOTICE: extension "btree_gist" already
> exists, skipping
> [Fri May 1 04:45:58 2015] init done at count_upsert_exclusion.pl line 106.
>
>
> (I ssh into server, check progress). Then, due to some issue with the
> scheduler or something, progress continues:
>
> [Fri May 1 05:17:57 2015] sum is 462
> [Fri May 1 05:17:57 2015] count is 8904
> [Fri May 1 05:17:58 2015] normal exit at 1430457478 after 128000
> items processed at count_upsert_exclusion.pl line 192.
> trying 128 clients:
Hmm, so it was stuck for half an hour at that point? Why do you think it
was a livelock?
> This is the same server that I shared credentials with you for. Feel
> free to ssh in and investigate it yourself.
I logged in, but the system seems very unresponsive in general. I just
started "apt-get install gdb" on it, to investigate what the backends
are stuck at. It's been running for about 30 minutes now, and I'm still
waiting...
- Heikki
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: hlinnaka@iki.fi, pg@heroku.com, andres@anarazel.de, jeff.janes@gmail.com, sfrost@snowman.net, dean.a.rasheed@gmail.com, bruce@momjian.us, pgsql-hackers@postgresql.org
Subject: Re: INSERT ... ON CONFLICT UPDATE/IGNORE 4.0
In-Reply-To: <55439214.6080506@iki.fi>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox