Horton

Re: new heapcheck contrib module

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

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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: 2020-10-22T21:23:19Z
Lists: pgsql-hackers 
Mark Dilger <mark.dilger@enterprisedb.com> writes:
> Yeah, I'm already looking at that.  The logic in verify_heapam skips over line pointers that are unused or dead, and the test is reporting zero corruption (and complaining about that), so it's probably not going to help to overwrite all the line pointers with this particular bit pattern any more than to just overwrite the first one, as it would just skip them all.

> I think the test should overwrite the line pointers with a variety of different bit patterns, or one calculated to work on all platforms.  I'll have to write that up.

What we need here is to produce the same test results on either
endianness.  So probably the thing to do is apply the equivalent
of ntohl() to produce a string that looks right for either host
endianness.  As a separate matter, you'd want to test corruption
producing any of the four flag bitpatterns, probably.

It says here you can use Perl's pack/unpack functions to get
the equivalent of ntohl(), but I've not troubled to work out how.

			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.