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Message-ID: <2e78013d0807040350m3b2913cfkceaa70d8f9d697c2@mail.gmail.com>
Date: Fri, 4 Jul 2008 16:20:03 +0530
From: "Pavan Deolasee" <pavan.deolasee@gmail.com>
To: "Heikki Linnakangas" <heikki@enterprisedb.com>
Subject: Re: page macros cleanup
Cc: "Zdenek Kotala" <Zdenek.Kotala@sun.com>,
	PostgreSQL-patches <pgsql-patches@postgresql.org>
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On Fri, Jul 4, 2008 at 3:37 PM, Heikki Linnakangas
<heikki@enterprisedb.com> wrote:
>
>
> I think this is the way it should be:
>
> #define HashMaxItemSize \
>        (BLCKSZ - \
>         SizeOfPageHeaderData - \
>         MAXALIGN(sizeof(HashPageOpaqueData)) - \
>         sizeof(ItemIdData))
>

I am wondering if this would fail for corner case if HashMaxItemSize
happened to be unaligned. For example, if (itemsz < HashMaxItemSize <
MAXALIGN(itemsz), PageAddItem() would later fail with a not-so-obvious
error. Should we just MAXALIGN_DOWN the HashMaxItemSize ?

Thanks,
Pavan


-- 
Pavan Deolasee
EnterpriseDB http://www.enterprisedb.com