Hi, On 2022-03-22 16:06:40 -0700, Nathan Bossart wrote: > On Thu, Mar 17, 2022 at 04:45:28PM -0700, Nathan Bossart wrote: > > I think this one requires some more work, and it needn't be a priority for > > v15, so I've adjusted the commitfest entry to v16 and moved it to the next > > commitfest. > > Here is a new patch. The main differences from v3 are in > heapam_visibility.c. Specifically, instead of trying to work the infomask > checks into the visibility logic, I added a new function that does a couple > of assertions. This function is called at the beginning of each visibility > function. > > What do folks think? The options I've considered are 1) not adding any > such checks to heapam_visibility.c, 2) only adding assertions like the > attached patch, or 3) actually using elog(ERROR, ...) when the invalid bit > patterns are detected. AFAICT (1) is more in line with existing invalid > bit patterns (e.g., XMAX_COMMITTED + XMAX_IS_MULTI). There are a couple of > scattered assertions, but most code paths don't check for it. (2) adds > additional checks, but only for --enable-cassert builds. (3) would add > checks even for non-assert builds, but there would presumably be some > performance cost involved.
> From 2d6b372cf61782e0fd52590b57b1c914b0ed7a4c Mon Sep 17 00:00:00 2001 > From: Nathan Bossart <nathandboss...@gmail.com> > Date: Tue, 22 Mar 2022 15:35:34 -0700 > Subject: [PATCH v4 1/1] disallow XMAX_COMMITTED + XMAX_LOCK_ONLY Just skimming this thread quickly, I really have no idea what this is trying to achieve and the commit message doesn't help either... I didn't read the referenced thread, but I shouldn't have to, to get a basic idea. Greetings, Andres Freund
