On Tue, 2 May 2006, Tom Lane wrote:
> Heikki Linnakangas <hlinnaka@iki.fi> writes:
>> On Tue, 2 May 2006, Tom Lane wrote:
>>> Backwards scan may break this whole concept; are you sure you've thought
>>> it through?
>
>> I think so. The patch doesn't change the walk-left code. Do you have
>> something specific in mind?
>
> I'm worried about synchronization, particularly what happens if the page
> gets deleted from under you while you don't have it pinned.
AFAICS, shouldn't happen. The half-dead system makes sure that a page
won't get deleted while a scan might still be interested in it. It
doesn't depend on pins.
- Heikki
