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Re: Do we need so many hint bits?

Andres Freund <andres@2ndquadrant.com>

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From: Andres Freund <andres@2ndquadrant.com>
To: Jeff Davis <pgsql@j-davis.com>
Cc: Atri Sharma <atri.jiit@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Pg Hackers <pgsql-hackers@postgresql.org>, Merlin Moncure <mmoncure@gmail.com>
Date: 2012-11-19T18:49:27Z
Lists: pgsql-hackers 
On 2012-11-19 10:46:37 -0800, Jeff Davis wrote:
> On Tue, 2012-11-20 at 00:13 +0530, Atri Sharma wrote:
> 
> > My mistake...I thought we were more concerned about the cost of
> > locking.
> > 
> > I agree, locking many data pages simultaneously could be hazardous.
> > 
> > This requires more thought.Maybe removing PD_ALL_VISIBLE isnt such a
> > great idea after all...
> 
> As I said elsewhere in the thread, I'm not planning to introduce any
> additional locking. There is already precedent in IndexOnlyNext.

Yea, but that precedent is only valid because IOS does check for a MVCC
snapshots. Also it doesn't set anything.

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
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