On Mon, Jul 18, 2016 at 10:05 AM, Tom Lane <t...@sss.pgh.pa.us> wrote:
> Jan Wieck <j...@wi3ck.info> writes: > > In the meantime, would it be appropriate to backpatch the double linking > > of memory context children at this time? I believe it has had plenty of > > testing in the 9.6 cycle to be sure it didn't break anything. > > I'm concerned about the ABI breakage risk from changing a data structure > as fundamental as MemoryContext. Yeah, code outside utils/mmgr probably > *shouldn't* be looking at that struct, but that doesn't mean it isn't. > In the past we've generally only taken that sort of risk when there was > no other way to fix a bug; and this patch isn't a bug fix. While this > does help performance in some corner cases, I don't think it's enough of > an across-the-board win to justify the risk of back-patching. > I would consider mucking with the linked lists of memory context children inside of 3rd party code a really bad idea, but I concede. It isn't a bug fix and there is that small risk that somebody did precisely that, so no backpatch. Regards, Jan -- Jan Wieck Senior Postgres Architect http://pgblog.wi3ck.info
