Re: WAL to RAW devices ?

Probably you missed that part... In my setup, I need at least
2 boxes going after those files, while 3rd box keeps on writing
to them... I can't mount ext2 even in R/O mode while it's being
written to by another guy. I can't unmount it before mounting
exclusively on any of them either, since PG will be writing to
that location. The only way is to do the WAL shipping, which
probably wouldn't be that bad since the copying would be done
via DMA, but still isn't as good as it could be since that would
utilize the same spindles...


On Fri, 2007-08-31 at 20:23 -0400, Alvaro Herrera wrote:
> Alex Vinogradovs wrote:
> > WAL segments already have their structure. Filesystem would be an
> > overhead,
> 
> In this case you can choose a filesystem with lower overhead.  For
> example with WAL you don't need a journalling filesystem at all, so
> using ext2 is not a bad idea.  For Pg data files, you need journalling
> of metadata only, not of data; the latter is provided by WAL.  So you
> can mount the data filesystem with the option data=writeback.
>