Re: Question regarding the database page layout. - Mailing list pgsql-hackers

From Gregory Stark
Subject Re: Question regarding the database page layout.
Date
Msg-id 87r682sgn2.fsf@oxford.xeocode.com
Whole thread Raw
In response to Re: Question regarding the database page layout.  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Question regarding the database page layout.  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane <tgl@sss.pgh.pa.us> writes:

> "Ryan Bradetich" <rbradetich@gmail.com> writes:
>> The patch concept is fairly simple.
>
>>    1.  Add a new boolean local variable: require_max_align
>> (initialized to false).
>
> This really can't possibly work, because you'd need to propagate
> knowledge of the tuple's alignment requirement all over the place.
> In particular, how would code *reading* the tuple know where the
> data starts?  

Uh, at t_hoff, no?

> Also, I don't think you get (very much of) the actual benefit unless the
> code that inserts tuples into disk pages knows to do something different in
> the int-align case.

+1

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's PostGIS support!


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