On Mon, Apr 25, 2011 at 8:36 AM, Leonardo Francalanci <m_lists@yahoo.it> wrote:
> The only data we can't rebuild it's the heap. So what about an option for UNlogged indexes on a LOGged table? It
wouldalways preserve data, and it would 'only' cost a rebuilding of the indexes in case of an unclean shutdown. I think
itwould give a boost in performance for all those cases where the IO (especially random IO) is caused by the indexes,
andit doesn't look too complicated (but maybe I'm missing something).
>
> I proposed the unlogged to logged patch (BTW has anyone given a look at it?) because we partition data based on a
timestamp,and we can risk loosing the last N minutes of data, but after N minutes we want to know data will always be
there,so we would like to set a partition table to 'logged'.
I agree that unlogged indexes on a logged heap are better for
resilience and are likely to be the best first step.
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services