On Tuesday, September 18, 2012 04:18:01 AM Robert Haas wrote:
> >> Maybe what we should do is - if this is an end-of-recovery checkpoint
> >> - *assert* that the BM_PERMANENT bit is set on every buffer we find.
> >> That would provide a useful cross-check that we don't have a bug
> >> similar to the one Jeff already fixed in any other code path.
> >
> > I haven't looked into the details, but can't a new unlogged relation be
> > created since the last checkpoint and thus have pages in s_b?
>
> Data changes to unlogged relations are not WAL-logged, so there's no
> reason for recovery to ever read them. Even if such a reason existed,
> there wouldn't be anything to read, because the backing files are
> unlinked before WAL replay begins.
Back then I thought that resetting the relation by copying the init fork might
use the buffer cache. It doesn't atm...
Andres
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Andres Freund http://www.2ndQuadrant.com/
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