Re: change in LOCK behavior

From: Simon Riggs <simon(at)2ndQuadrant(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Robert Haas <robertmhaas(at)gmail(dot)com>, Tomas Vondra <tv(at)fuzzy(dot)cz>, Thom Brown <thom(at)linux(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: change in LOCK behavior
Date: 2012-10-11 08:57:28
Message-ID: CA+U5nMJaNqPNWcaD+T03FgD_USM7k5YGh2zsFn7pprVJLRjJbA@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 11 October 2012 01:43, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> I think we have to revert and go back to the drawing board on this.

Given that change was also sold on the basis of higher performance, I
suggest we retest performance to check there is a gain. If there is
still a gain, I suggest we add this as a SIGHUP option, default to
off, rather than completely remove it.

I might also observe since the problem only happens with lock waits,
perhaps we can set a flag can_reuse_snapshot that gets cleared if we
need to perform a lock wait before executing the main statement.

--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Etsuro Fujita 2012-10-11 09:10:58 Re: FDW for PostgreSQL
Previous Message Hannu Krosing 2012-10-11 08:47:51 Re: [PATCH 8/8] Introduce wal decoding via catalog timetravel