On Mon, 01 Jul 2002 12:40:35 +0200, I wrote:
>Bytes saved on architectures with 4/8 byte alignment:
> hoff bytes
>natts bitmaplen hoff72 oidoff woo saved
> 0 28/32 24 24/24 4/8
>1-8 1 28/32 24 24/24 4/8
>9-40 2-5 32/32 28 28/32 4/0
>41-72 6-9 36/40 32 32/32 4/8
In this table oidoff contains wrong values, it is from my first
approach, where I tried to put oid at the first INTALIGNed position
after t_bits. The table should be:
bitmap hoff bytes
natts len hoff1 hoff2 oidoff woo saved 0 32 28/32 24/28 24 4/8
1-8 1 32 28/32 24/28 24 4/8
9-40 2-5 36/40 32 28 28/32 4/0
41-72 6-9 40 36/40 32/36 32 4/8
where hoff1 is the MAXALIGNed length of the tuple header with a v7.2
compatible tuple header format (with bitmaplen patch included);
hoff2 is the header size after the Xmin/Cid/Xmax patch, which is still
being discussed on -patches and -hackers;
with this proposal, if a table has oids, oidoff is the offset of the
oid and header size equals hoff2;
hoff woo is the header size without oid;
bytes saved is relative to hoff2.
I apologize for the confusion.
ServusManfred
