Horton

Re: new heapcheck contrib module

Tom Lane <tgl@sss.pgh.pa.us>

View thread View on postgr.es
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Dilger <mark.dilger@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Peter Geoghegan <pg@bowt.ie>, "Andrey M. Borodin" <x4mmm@yandex-team.ru>, Stephen Frost <sfrost@snowman.net>, Michael Paquier <michael@paquier.xyz>, Amul Sul <sulamul@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Andres Freund <andres@anarazel.de>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2020-10-23T18:51:01Z
Lists: pgsql-hackers 
Hmm, we're not out of the woods yet: thorntail is even less happy
than before.

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=thorntail&dt=2020-10-23%2018%3A08%3A11

I do not have 64-bit big-endian hardware to play with unfortunately.
But what I suspect is happening here is less about endianness and
more about alignment pickiness; or maybe we were unlucky enough to
index off the end of the shmem segment.  I see that verify_heapam
does this for non-redirect tuples:

            /* Set up context information about this next tuple */
            ctx.lp_len = ItemIdGetLength(ctx.itemid);
            ctx.tuphdr = (HeapTupleHeader) PageGetItem(ctx.page, ctx.itemid);
            ctx.natts = HeapTupleHeaderGetNatts(ctx.tuphdr);

with absolutely no thought for the possibility that lp_off is out of
range or not maxaligned.  The checks for a sane lp_len seem to have
gone missing as well.

			regards, tom lane

Commits

  1. Add pg_amcheck, a CLI for contrib/amcheck.

  2. Refactor and generalize the ParallelSlot machinery.

  3. Generalize parallel slot result handling.

  4. Move some code from src/bin/scripts to src/fe_utils to permit reuse.

  5. Factor pattern-construction logic out of processSQLNamePattern.

  6. Doc: clean up verify_heapam() documentation.

  7. Fix more portability issues in new amcheck code.

  8. Fix portability issues in new amcheck test.

  9. Try to avoid a compiler warning about using fxid uninitialized.

  10. Extend amcheck to check heap pages.

  11. Adjust walsender usage of xlogreader, simplify APIs

  12. Improve checking of child pages in contrib/amcheck.

  13. Sanitize line pointers within contrib/amcheck.

  14. Fix possible sorting error when aborting use of abbreviated keys.