Re: stack usage in toast_insert_or_update() - Mailing list pgsql-hackers

From Tom Lane
Subject Re: stack usage in toast_insert_or_update()
Date
Msg-id 19395.1170349728@sss.pgh.pa.us
Whole thread Raw
In response to Re: stack usage in toast_insert_or_update()  (Jan Wieck <JanWieck@Yahoo.com>)
List pgsql-hackers
Jan Wieck <JanWieck@Yahoo.com> writes:
> On 1/31/2007 12:41 PM, Tom Lane wrote:
>> We can't change TOAST_MAX_CHUNK_SIZE without forcing an initdb, but I
>> think that it would be safe to remove the MAXALIGN'ing of the tuple
>> size in the tests in heapam.c, that is

> Can't we maxalign the page header in the calculations?

Actually, the page header size *is* maxaligned.  The problem is that
TOAST_TUPLE_THRESHOLD isn't.

We could make it so, but that would change TOAST_MAX_CHUNK_SIZE thus
forcing an initdb.  I think simply removing the MAXALIGN operations
in the code is a better answer, as it eliminates some rather pointless
overhead.  There's no particular reason why the threshold needs to be
maxaligned ...
        regards, tom lane


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