Horton

Re: Avoiding repeated snapshot computation

Tom Lane <tgl@sss.pgh.pa.us>

View thread
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers@postgresql.org, Pavan Deolasee <pavan.deolasee@gmail.com>
Date: 2011-11-26T20:52:17Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Slightly reorganize struct SnapshotData.

Andres Freund <andres@anarazel.de> writes:
> You could also try if it makes a difference reducing SnapshotData to one 
> instead of two cachelines. The data itself fits into one without problems.
> Trivial patch attached.

On what grounds do you argue that this patch gets SnapshotData into one
cacheline today (and on what hardware), or that it will continue to do
so in the future?  If we're this close to the edge then any future
addition to the struct will destroy the point.  I'd just as soon keep
the fields in a logical order.

			regards, tom lane