[HACKERS] Re: heap/SLRU verification, relfrozenxid cut-off, and freeze-the-dead bug (Was: amcheck (B-Tree integrity checking tool))

2017-10-18 Thread Peter Geoghegan
On Mon, Oct 16, 2017 at 8:09 PM, Noah Misch wrote: > That presupposes construction of two pieces of software, the server and the > checker, such that every disagreement is a bug in the server. But checkers > get bugs just like servers get bugs. You make a good point, which is

[HACKERS] Re: heap/SLRU verification, relfrozenxid cut-off, and freeze-the-dead bug (Was: amcheck (B-Tree integrity checking tool))

2017-10-16 Thread Noah Misch
On Mon, Oct 16, 2017 at 12:57:39PM -0700, Peter Geoghegan wrote: > On Fri, Oct 13, 2017 at 7:09 PM, Noah Misch wrote: > > The checker should > > consider circumstances potentially carried from past versions via > > pg_upgrade. > > Right. False positives are simply

[HACKERS] Re: heap/SLRU verification, relfrozenxid cut-off, and freeze-the-dead bug (Was: amcheck (B-Tree integrity checking tool))

2017-10-16 Thread Peter Geoghegan
On Fri, Oct 13, 2017 at 7:09 PM, Noah Misch wrote: > All good questions; I don't know offhand. Discovering those answers is > perhaps the chief labor required of such a project. ISTM that by far the hardest part of the project is arriving at a consensus around what a good set

[HACKERS] Re: heap/SLRU verification, relfrozenxid cut-off, and freeze-the-dead bug (Was: amcheck (B-Tree integrity checking tool))

2017-10-13 Thread Noah Misch
On Mon, Oct 09, 2017 at 05:19:11PM -0700, Peter Geoghegan wrote: > On Sun, Oct 16, 2016 at 6:46 PM, Noah Misch wrote: > > - Verify agreement between CLOG, MULTIXACT, and hint bits. > > This is where it gets complicated, I think. This is what I really want > to talk about. > >