Re: snapshot too old, configured by time - Mailing list pgsql-hackers

From Kevin Grittner
Subject Re: snapshot too old, configured by time
Date
Msg-id CACjxUsM4K3fLe-4hwaqEnkzKdx0Y89Aow-920EA7vik1SOYfDA@mail.gmail.com
Whole thread Raw
In response to Re: snapshot too old, configured by time  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: snapshot too old, configured by time  (Kevin Grittner <kgrittn@gmail.com>)
List pgsql-hackers
On Tue, Apr 19, 2016 at 12:49 PM, Alvaro Herrera
<alvherre@2ndquadrant.com> wrote:

> Well, it seems I'm outvoted.

The no-op change to attempt to force an explicit choice of whether
to test for snapshot age after calling BufferGetPage() has been
reverted.  This eliminates about 500 back-patching pain points in
65 files.

In case anyone notices some code left at the bottom of bufmgr.h
related to inline functions, that was left on purpose, because I am
pretty sure that the fix for the performance regression observed
when the "snapshot too old" feature is disabled will involve making
at least part of TestForOldSnapshot() an inline function -- so it
seemed dumb to rip that out now only to put it back again right
away.

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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