> 4. How exactly should a killed index tuple be marked on-disk? While there
> is one free bit available in IndexTupleData.t_info, I would prefer to use
> that bit to expand the index tuple size field to 14 bits instead of 13.
> (This would allow btree index entries to be up to 10K when BLCKSZ is 32K,
> rather than being hard-limited to 8K.)
While I agree that it might be handy to save this bit for future use,
I do not see any value in increasing the max key length from 8k,
especially when the new limit is then 10k. The limit is already 32 *
the max key size of some other db's, and even those 256 bytes are usually
sufficient.
Andreas