Re: POC: Cleaning up orphaned files using undo logs

On Mon, Aug 19, 2019 at 5:16 PM Andres Freund <andres@anarazel.de> wrote:
> Well, my main point, which so far has largely been ignored, was that we
> may not acquire page locks when we still need to search for victim
> buffers later. If we don't need to lock the pages up-front, but only do
> so once we're actually copying the records into the undo pages, then we
> don't a separate phase to acquire the locks. We can still hold all of
> the page locks at the same time, as long as we just acquire them at the
> later stage.

+1 for that approach.  I am in complete agreement.

> My secondary point was that *none* of this actually is
> documented, even if it's entirely unobvious to the reader that the
> relevant code can only run during WAL insertion, due to being pretty far
> removed from that.

+1 also for properly documenting stuff.

-- 
Robert Haas
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