Horton

Re: [HACKERS] Performance while loading data and indexing

Neil Conway <neilc@samurai.com>

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From: Neil Conway <neilc@samurai.com>
To: Greg Copeland <greg@CopelandConsulting.Net>
Cc: Neil Conway <neilc@samurai.com>, Bruce Momjian <pgman@candle.pha.pa.us>, shridhar_daithankar@persistent.co.in, PostgresSQL Hackers Mailing List <pgsql-hackers@postgresql.org>, PostgresSQL General Mailing List <pgsql-general@postgresql.org>
Date: 2002-09-26T21:17:30Z
Lists: pgsql-hackers, pgsql-performance, pgsql-general 
Greg Copeland <greg@CopelandConsulting.Net> writes:
> On Thu, 2002-09-26 at 16:03, Neil Conway wrote:
> > I'm not really familiar with the reasoning behind ext2's
> > reputation as recovering poorly from crashes; if we fsync a WAL
> > record to disk before we lose power, can't we recover reliably,
> > even with ext2?
> 
> Well, I have experienced data loss from ext2 before.  Also, recovery
> from crashes on large file systems take a very, very long time.

Yes, but wouldn't you face exactly the same issues if you ran a
UFS-like filesystem in asynchronous mode? Albeit it's not the default,
but performance in synchronous mode is usually pretty poor.

The fact that ext2 defaults to asynchronous mode and UFS (at least on
the BSDs) defaults to synchronous mode seems like a total non-issue to
me. Is there any more to the alleged difference in reliability?

Cheers,

Neil

-- 
Neil Conway <neilc@samurai.com> || PGP Key ID: DB3C29FC