Date: Fri, 04 Jul 2008 09:31:29 +0200
From: Zdenek Kotala <Zdenek.Kotala@Sun.COM>
Subject: Re: page macros cleanup
In-reply-to: <2e78013d0807030450m4cab60d0jd99d1acce59fae56@mail.gmail.com>
To: Pavan Deolasee <pavan.deolasee@gmail.com>
Cc: PostgreSQL-patches <pgsql-patches@postgresql.org>
Message-id: <486DD1D1.50604@sun.com>
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Pavan Deolasee napsal(a):
> On Fri, Jun 13, 2008 at 9:38 PM, Zdenek Kotala <Zdenek.Kotala@sun.com> wrote:
>> I attached code cleanup which is related to in-place upgrade. I replace
>> direct access to PageHeader structure with already existing macros and I
>> removed also unnecessary retyping.
> 
> A quick review comment:

Thanks you for your review,

> 
> One thing I noticed is that the modified definition of HashMaxItemSize
> now does not account for the size of ItemId which may not be the right
> thing. Please recheck that.

Good catch. I lost in basic arithmetic. What I see now that original definition 
count sizeof(ItemIdData) twice and on other side it does not take care about 
MAXALING correctly. I think correct formula is:

#define HashMaxItemSize(page) \
         (PageGetPageSize(page) - \
           ( MAXALIGN(SizeOfPageHeaderData + sizeof(ItemIdData))+ \
             MAXALIGN(sizeof(HashPageOpaqueData)) \
           )\
          )

What do you think?

	Thanks for your comments Zdenek


-- 
Zdenek Kotala              Sun Microsystems
Prague, Czech Republic     http://sun.com/postgresql