Horton

Re: good pc but bad performance,why?

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: "scott.marlowe" <scott.marlowe@ihs.com>, Andrew McMillan <andrew@catalyst.net.nz>, huang yaqin <hyq@gthome.com>, pgsql-performance@postgresql.org
Date: 2004-04-08T01:33:34Z
Lists: pgsql-performance 
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > scott.marlowe wrote:
> >>> There is no real need (or benefit) from having the database on a
> >>> journalled filesystem - the journalling is only trying to give similar
> >>> sorts of guarantees to what the fsync in PostgreSQL is doing.
> >> 
> >> Is this true?  I was under the impression that without at least meta-data 
> >> journaling postgresql could still be corrupted by power failure.
> 
> > It is false.  ext2 isn't crash-safe, and PostgreSQL needs an intact file
> > system for WAL recovery.
> 
> But it should be okay to set the filesystem to journal only its own
> metadata.  There's no need for it to journal file contents.

Can you set ext2 to journal metadata?  I didn't know it could do that.

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