Re: Index-only scan performance regression

On Tue, Jan 31, 2012 at 2:15 PM, Dean Rasheed <dean.a.rasheed@gmail.com> wrote:
> In the case when we're asked to clear a bit, it would first try to pin
> the relevant page, which would go through vm_readbuf() with extend set
> to true. Then vm_extend() would notice that the visibility map had
> already been extended, and it would read in the new page with the set
> bit. So this case would continue to work, wouldn't it?

Ah, maybe.  I haven't tried to code it up.  Do you want to take a crack at it?

-- 
Robert Haas
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