Re: age(xid) on hot standby

On 9 May 2012 15:34, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
>>> We should just use MyPgXact->xid
>>> rather than add more to the transaction path
>>>
>>> I'll simplify the patch and commit.
>
>> Committed, but forgot to give appropriate credit. Sorry about that.
>
> This patch didn't fix things, it broke things.  The former guarantee
> that age's reference point would hold still throughout a transaction
> just disappeared.
>
> What I read your previous suggestion to be was that age() would keep
> local state and use inspection of the current VXID to tell if its
> cache was stale.  That would keep the fix localized (which I agree
> is a good idea) without losing the stability guarantee.

Gotcha. Will fix.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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