Re: BUG #13657: Some kind of undetected deadlock between query and "startup process" on replica.

On Wed, Oct 21, 2015 at 4:42 AM, Michael Paquier <michael.paquier@gmail.com=
>
wrote:

> On Mon, Oct 5, 2015 at 5:47 PM, Maxim Boguk <maxim.boguk@gmail.com> wrote=
:
> > I would like to check 9.4.5 but I prefer wait for release and not build
> it
> > by hands, and from my experience building from git tree could be tricky
> as I
> > don't have root access to install additional packages on the server.
> > However, I will try it in next few days (if I get an permission).
>
> Maxim, did you get the occasion to test your setup with 9.4.5? It
> seems that your environment is more likely to reproduce this deadlock.


=E2=80=8BSorry for late response, after upgrade to 9.4.5 this issue never h=
appened
anymore (zero occurrences during the last week).
Before all cases of deadlock happened during wal replay of 2 specific
tables (and only them) of the database of few thousands. These tables are
somewhat special in sense they have medium insert/delete load but most time
they have zero alive tuples and size changes from 0 block to 1-2 block and
back quite a lot.=E2=80=8B

=E2=80=8B I suppose deadlock had been happened when replay process replayin=
g
truncation to zero pages after vacuum on the master db (but it's mostly
theory with no good evidence).
 =E2=80=8B


--=20
Maxim Boguk
Senior Postgresql DBA
http://www.postgresql-consulting.ru/ <http://www.postgresql-consulting.com/=
>

Phone RU: +7 910 405 4718
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