Re: DropRelFileNodeBuffers API change (was Re: [BUGS] BUG #5599: Vacuum fails due to index corruption issues)

Robert Haas <robertmhaas@gmail.com> writes:
> I really hate this solution, because writing out data that we're about
> to throw away just in case we can't actually throw it away seems like
> a real waste from a performance standpoint.

We went around on this already in the pgsql-bugs thread.  I don't much
like it either, but there isn't any better solution that seems safe
enough to back-patch.

> Could we avoid this
> altogether by allocating a new relfilenode on truncate?

Then we'd have to copy all the data we *didn't* truncate, which is
hardly likely to be a win.
        regards, tom lane