Re: DBT-3 with SF=20 got failed - Mailing list pgsql-hackers

From Robert Haas
Subject Re: DBT-3 with SF=20 got failed
Date
Msg-id CA+TgmoYPyQTsSf6gMrRt5SWnCHz8mLOKwqNp3S5OeW4S1_tFeA@mail.gmail.com
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In response to Re: DBT-3 with SF=20 got failed  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
Responses Re: DBT-3 with SF=20 got failed  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
List pgsql-hackers
On Thu, Sep 24, 2015 at 5:50 AM, Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> I however quite dislike the dismissal of the possible impact. It should be
> the responsibility of the person introducing the change to show that no such
> impact actually exists, not just waving it off as "unbased on any evidence"
> when there's no evidence presented.

So, we're talking about determining the behavior in a case that
currently fails.  Making it behave like a case that currently works
can't but be an improvement.  Making it do something that currently
never happens might be better still, or it might be equivalent, or it
might be worse.  I just don't buy the argument that somebody's got to
justify on performance grounds a decision not to allocate more memory
than we currently ever allocate.  That seems 100% backwards to me.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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