Did we make any headway on this? ---------------------------------------------------------------------------
On Sat, Nov 19, 2011 at 12:31:09PM -0500, Stephen Frost wrote: > Andres, > > * Andres Freund (and...@anarazel.de) wrote: > > For that I added new functions/defines which allocate all the needed memory > > in > > one hunk: > > list_immutable_make$n(), > > List *list_new_immutable_n(NodeTag t, size_t n); > > List *list_make_n(NodeTag t, size_t n, ...); > > A while back, I posted a patch to try and address this same issue. The > approach that I took was to always pre-allocate a certain (#defined) > amount (think it was 5 or 10 elements). There were a number of places > that caused problems with that approach because they hacked on the list > element structures directly (instead of using the macros/functions)- > you'll want to watch out for those areas in any work on lists. > > That patch is here: > http://archives.postgresql.org/pgsql-hackers/2011-05/msg01213.php > > The thread on it might also be informative. > > I do like your approach of being able to pass the ultimate size of the > list in.. Perhaps the two approaches could be merged? I was able to > make everything work with my approach, provided all the callers used the > list API (I did that by making sure the links, etc, actually pointed to > the right places in the pre-allocated array). One downside was that the > size ended up being larger that it might have been in some cases. > > Thanks, > > Stephen -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
