On 10/26/2013 01:20 AM, Josh Berkus wrote:
> On 10/24/2013 07:19 PM, Tom Lane wrote:
>> In any case, it's very far from obvious to me that CLUSTER ought
>> to throw away information by default, which is what you're proposing.
>
> The problem here is that you're thinking of the 1/10 of 1% of our users
> who have a serious PostgreSQL failure and post something on the lists
> for help, for which XID forensic information is useful. As opposed to
> the 99.9% of our users for whom deferred freezing is a performance
> burden. While I realize that the 0.1% of users are more likely to have
> contact with you, personally, it's still bad policy for the project.
Strong +1 from me. Doing the performant, sensible, low-admin thing by
default is really important if you don't want a database that requires a
two year training course and a professional DBA to use. Some DB vendors
make that part of their business model, but personally at least that's
certainly not the direction I'd like to see Pg go in.
Autovacuum wrap-around prevention already gets rid of this info, it's
not like it's kept forever anyway.
Anything that makes the mechanics of bloat and vacuum less visible is a
big win as far as I'm concerned.
-- Craig Ringer http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services