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Modifying TOAST_TUPLE_THRESHOLD and TOAST_TUPLE_TARGET?

From: Shadar <shauldar(at)gmail(dot)com>
To: pgsql-hackers(at)postgresql(dot)org
Subject: Modifying TOAST_TUPLE_THRESHOLD and TOAST_TUPLE_TARGET?
Date: 2009-06-11 14:32:51
Message-ID: 23982524.post@talk.nabble.com (view raw or flat)
Thread:
Lists: pgsql-hackers
I notice that one of my tables gets TOASTed, about 40% of it. I read about
TOAST and understand the general motivation (get faster access to the
*other* columns). But in my case the big column (~2.5KB fixed width) is a
list (array) of values (not text) and the usage pattern is that I always
access a single row from the table by key and read the full list. So my
guess is TOAST is doing me more damage than good. Right?

I would have liked to disable TOAST (even altogether for my DB) - is there a
direct way to do this? Alternatively I thought of increasing
TOAST_TUPLE_THRESHOLD and TOAST_TUPLE_TARGET from 2KB (I believe this is the
default?) to 4KB? Do I have to change the source (
http://doxygen.postgresql.org/tuptoaster_8h-source.html here ?) and compile
a private version of Postgres?

Thanks, feel free to reply by email.

-- Shaul (info(at)shauldar(dot)com)
-- 
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