On Fri, 2009-03-13 at 11:17 -0700, Ben Chobot wrote:
> On Fri, 13 Mar 2009, Joshua D. Drake wrote:
>
> > On Fri, 2009-03-13 at 14:00 -0400, Tom Lane wrote:
> >> Marco Colombo <pgsql@esiway.net> writes:
> >>> You mean some layer (LVM) is lying about the fsync()?
> >>
> >> Got it in one.
> >>
> >
> > I wouldn't think this would be a problem with the proper battery backed
> > raid controller correct?
>
> It seems to me that all you get with a BBU-enabled card is the ability to
> get burts of writes out of the OS faster. So you still have the problem,
> it's just less like to be encountered.
A BBU controller is about more than that. It is also supposed to be
about data integrity. The ability to have unexpected outages and have
the drives stay consistent because the controller remembers the state
(if that is a reasonable way to put it).
Joshua D. Drake
>
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