Re: Index-only scans and non-MVCC snapshots - Mailing list pgsql-hackers

From Ryan Johnson
Subject Re: Index-only scans and non-MVCC snapshots
Date
Msg-id 53ACFD90.2020806@cs.utoronto.ca
Whole thread Raw
In response to Re: Index-only scans and non-MVCC snapshots  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: Index-only scans and non-MVCC snapshots  (Alvaro Herrera <alvherre@2ndquadrant.com>)
List pgsql-hackers
On 26/06/2014 11:04 PM, Alvaro Herrera wrote:
> Ryan Johnson wrote:
>> As part of a research project, I'm trying to change Read Committed
>> isolation to use HeapTupleSatisfiesNow rather than acquiring a new
>> snapshot at every command [1].
> Are you aware of this?
>
> commit 813fb0315587d32e3b77af1051a0ef517d187763
> Author: Robert Haas <rhaas@postgresql.org>
> Date:   Thu Aug 1 10:46:19 2013 -0400
>
>      Remove SnapshotNow and HeapTupleSatisfiesNow.
That would be wonderful news... if snapshots weren't so darned expensive 
to create.

I guess there's no avoiding that bottleneck now, though.

Ryan



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