Re: [HACKERS] getting rid of SnapshotNow

Robert Haas escribió:
> On Fri, Jul 19, 2013 at 1:27 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> > Why not tell people to use SnapshotDirty if they need a
> > not-guaranteed-consistent result?  At least then it's pretty obvious
> > that you're getting some randomness in with your news.

> On further reflection, I think perhaps pgrowlocks should just register
> a fresh MVCC snapshot and use that.  Using SnapshotDirty would return
> TIDs of unseen tuples, which does not seem to be what is wanted there.

I think seeing otherwise invisible rows is useful in pgrowlocks.  It
helps observe the effects on tuples written by concurrent transactions
during experimentation.  But then, maybe this functionality belongs in
pageinspect instead.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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