Re: High Performance/High Reliability File system on SuSE64

Christopher Weimann wrote:
> On 01/23/2004-10:18AM, Joshua D. Drake wrote:
> >
> > XFS also has the interesting ability (although I have yet to test it)
> > that will allow you
> > to take a snapshot of the filesystem. Thus you can have filesystem level
> > backups
> > of the PGDATA directory that are consistent even though the database is
> > running.
>
> You can do snapshots in FreeBSD 5.x with UFS2 as well but that (
> nor XFS snapshots ) will let you backup with the database server
> running.  Just because you will get the file exactly as it was at
> a particular instant does not mean that the postmaster did not
> still have some some data that was not flushed to disk yet.

Uh, yea, it does.  If the snapshot includes all of /data, including
WAL/xlog, you can then back up the snapshot and restore it on another
machine.  It will restart just like a crash.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
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