From: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | Manfred Koizar <mkoi-pg(at)aon(dot)at>, pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Number of attributes in HeapTupleHeader |
Date: | 2002-06-12 18:23:16 |
Message-ID: | 200206121823.g5CINGq14824@candle.pha.pa.us |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Tom Lane wrote:
> I said:
> > Sorry, you used up your chance at claiming that t_hoff is dispensable.
> > If we apply your already-submitted patch, it isn't.
>
> Wait, I take that back. t_hoff is important to distinguish how much
> bitmap padding there is on a particular tuple --- but that's really
> only interesting as long as we aren't forcing dump/initdb/reload.
> If we are changing anything else about tuple headers, then that
> argument becomes irrelevant anyway.
>
> However, I'm still concerned about losing safety margin by removing
> "redundant" fields.
I just wanted to comment that redundancy in the tuple header, while
adding a very marginal amount to stability, is really too high a cost.
If we can save 4 bytes on every row stored, I think that is a clear win.
--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
From | Date | Subject | |
---|---|---|---|
Next Message | Jeroen T. Vermeulen | 2002-06-12 18:29:21 | Integrating libpqxx |
Previous Message | Manfred Koizar | 2002-06-12 18:14:13 | Re: Optimising inside transactions |