From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: hyrax vs. RelationBuildPartitionDesc
Date: Wed, 13 Mar 2019 14:38:02 -0300
Message-ID: <20190313173802.GA24768@alvherre.pgsql> (raw)
In-Reply-To: <CA+Tgmoabw8KW9rx6ThnUTR_ofJC8GwVaC+XMe7HkZvsG7J1rvA@mail.gmail.com>
On 2019-Mar-13, Robert Haas wrote:
> On Wed, Mar 13, 2019 at 12:42 PM Alvaro Herrera
> <alvherre@2ndquadrant.com> wrote:
> > I remember going over this code's memory allocation strategy a bit to
> > avoid the copy while not incurring potential leaks CacheMemoryContext;
> > as I recall, my idea was to use two contexts, one of which is temporary
> > and used for any potentially leaky callees, and destroyed at the end of
> > the function, and the other contains the good stuff and is reparented to
> > CacheMemoryContext at the end. So if you have any accidental leaks,
> > they don't affect a long-lived context. You have to be mindful of not
> > calling leaky code when you're using the permanent one.
>
> Well, that assumes that the functions which allocate the good stuff do
> not also leak, which seems a bit fragile.
A bit, yes, but not overly so, and it's less fragile that not having
such a protection. Anything that allocates in CacheMemoryContext needs
to be very careful anyway.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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-hackers@postgresql.org
Cc: alvherre@2ndquadrant.com, robertmhaas@gmail.com, pgsql-hackers@lists.postgresql.org
Subject: Re: hyrax vs. RelationBuildPartitionDesc
In-Reply-To: <20190313173802.GA24768@alvherre.pgsql>
* 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