Re: Refactoring log_newpage - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Refactoring log_newpage
Date
Msg-id 24908.1328198686@sss.pgh.pa.us
Whole thread Raw
In response to Re: Refactoring log_newpage  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers
Simon Riggs <simon@2ndQuadrant.com> writes:
> On Wed, Feb 1, 2012 at 10:42 PM, Jim Nasby <jim@nasby.net> wrote:
>> But we already had RelFileNode; wouldn't that be enough to tell what rmgr was responsible for the new page? Can 2
differentrmgrs write to the same file node?
 

> No, but which one? No way to tell unless you have full list of
> relfilenodes and check each one. So btree changes look like heap
> changes etc..

What I'm not following is why we should care.  There are no cases at
present where this matters, and no proposed patches (that I know of)
that would make it matter.  If an individual rmgr needs control of
what happens during a given operation, it wouldn't use XLOG_NEWPAGE
to represent the operation.  End of problem.  You haven't provided
any convincing argument why this needs to be changed globally.
        regards, tom lane


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