Re: Set hint bits upon eviction from BufMgr

On Mon, Mar 28, 2011 at 9:48 AM, Merlin Moncure <mmoncure@gmail.com> wrote:
> I'd like to experiment on this and see what comes out.

Great!

> If the
> bgwriter was to be granted the ability to inspect buffers and set
> hints, it needs to be able to peek in and inspect the buffer itself
> which it currently doesn't do FWICT.

That matches my understanding.

> I was thinking about setting a
> flag in the buffer (BM_HEAP) that gets set by the loader which flags
> the buffer for later inspection.  Is there a simpler way to do this?

Hmm.  That's slightly crufty, but it might be OK.  At least, I don't
have a better idea.

> I think you guys are correct: the logic belongs in the bgwriter.
> Generally speaking, it looks like the best route to minimizing hint
> bit pain is to if at all possible write them out set so they don't
> have to be rewritten later (Stephen's approach to leverage in
> transaction table creation is another way of attempting to do that).

Yeah.

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Robert Haas
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