Re: compact flash disks? - Mailing list pgsql-performance

From Magnus Hagander
Subject Re: compact flash disks?
Date
Msg-id 20070308084823.GA7216@svr2.hagander.net
Whole thread Raw
In response to Re: compact flash disks?  ("James Mansion" <james@mansionfamily.plus.com>)
Responses Re: compact flash disks?
Re: compact flash disks?
List pgsql-performance
On Thu, Mar 08, 2007 at 06:24:35AM -0000, James Mansion wrote:
>
> In the long run, we are going to have to seriously rethink pg's use
> of WAL as the way we implement MVCC as it becomes more and more of a
> performance bottleneck.
> We have WAL because Stonebreaker made an assumption about the future
> dominance of optical media that has turned out to be false.
> ...and it's been one of pg's big issues every since.

Uh. pg didn't *have* WAL back when Stonebreaker was working on it. It
was added in PostgreSQL 7.1, by Vadim. And it significantly increased
performance at the time, since we no longer had to sync the datafiles
after every transaction commit.
(We also didn't have MVCC back in the Stonebreaker days - it was added
in 6.5)

That said, it's certainly possible that someone can find an even better
way to do it :-)

//Magnus

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