Re: collateral benefits of a crash-safe visibility map

On Tue, May 10, 2011 at 12:57 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
> Hmmm, do we really need to WAL log freezing?
>
> Can we break down freezing into a 2 stage process, so that we can have
> first stage as a lossy operation and a second stage that is WAL
> logged?

That might solve the relfrozenxid problem - set the bits in the heap,
sync the heap, then update relfrozenxid once the heap is guaranteed
safely on disk - but it again seems problematic for Hot Standby.

-- 
Robert Haas
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