Re: PostgreSQL as a local in-memory cache

On Wed, Jun 23, 2010 at 3:37 PM, Bruce Momjian <bruce@momjian.us> wrote:
> Tom Lane wrote:
>> Dimitri Fontaine <dfontaine@hi-media.com> writes:
>> > Josh Berkus <josh@agliodbs.com> writes:
>> >> a) Eliminate WAL logging entirely
>
> If we elimiate WAL logging, that means a reinstall is required for even
> a postmaster crash, which is a new non-durable behavior.
>
> Also, we just added wal_level = minimal, which might end up being a poor
> name choice of we want wal_level = off in PG 9.1.  Perhaps we should
> have used wal_level = crash_safe in 9.0.
>
> I have added the following TODO:
>
>        Consider a non-crash-safe wal_level that eliminates WAL activity
>
>            * http://archives.postgresql.org/pgsql-performance/2010-06/msg00300.php

I don't think we need a system-wide setting for that.  I believe that
the unlogged tables I'm working on will handle that case.

--
Robert Haas
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