Hello Zdenek, On Thu, Oct 9, 2008 at 12:38 AM, Zdenek Kotala <[EMAIL PROTECTED]> wrote: > Ryan Bradetich napsal(a): >> On Wed, Oct 8, 2008 at 10:59 PM, Zdenek Kotala <[EMAIL PROTECTED]> >> wrote:
>> I would like to see this patch (or some variant) go in if possible. >> Since the inplace >> upgrades a concern to you, is there anything I can do to help with the >> inplace >> upgrades to help offset the disruption this patch causes you? > > Yaah, wait until 8.5 :-). However, currently there is no clear consensus > which upgrade method is best. I hope that It will clear after Prato > developers meeting. Until this meeting I cannot say more. Heh, understood. :) I believe the proposed CRC patch also affects the heap page layout (adds the pd_checksum field to the PageHeaderData). [1] Just pointing out another patch that could affect you as well. My offer to help still stands. > I overlooked 'd' test. Your idea seems to me reasonable. Maybe, you could > test 'd' alignment only for NOT NULL values. Funny you should mention this. I had just started looking into this optimization to see if I could convince myself it would be safe. My initial conclusion indicates it would be safe, but I have not tested nor verified that yet. Having an independent proposal for this boosts my confidence even more. Thanks! > The problem there is add_item which it is used for indexes as well and they > has IndexTupleHeader structure. I'm not convenience about idea has two > different alignment for items on page. Just to clarify, this patch only affects heap storage when (i.e. the is_heap flag is set). I have not had a chance to analyze or see if I can reduce other storage types yet. > I guess another problem is with MAX_TUPLE_CHUNK_SIZE which uses MAXALIGN for > computing. It seems to me that toast chunk could waste a space anyway. > > And of course you should bump page layout version. Thanks. I will do. > I also suggest create function/macro to compute hoff and replace code with > this function/macro. Great. That is some of the feedback I was looking for. I did not implement it yet, because I wanted to see if the basic implementation was feasible first. Thanks again for your feedback! - Ryan [1] http://archives.postgresql.org/pgsql-hackers/2008-10/msg00070.php -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
