Horton

Re: backup manifests

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: David Steele <david@pgmasters.net>
Cc: Andres Freund <andres@anarazel.de>, Amit Kapila <amit.kapila16@gmail.com>, Suraj Kharage <suraj.kharage@enterprisedb.com>, tushar <tushar.ahuja@enterprisedb.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Rushabh Lathia <rushabh.lathia@gmail.com>, Tels <nospam-pg-abuse@bloodgate.com>, Andrew Dunstan <andrew.dunstan@2ndquadrant.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Jeevan Chalke <jeevan.chalke@enterprisedb.com>, vignesh C <vignesh21@gmail.com>
Date: 2020-03-30T00:47:40Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Try to avoid compiler warnings in optimized builds.

  2. Fix option related issues in pg_verifybackup.

  3. Add index term for backup manifest in documentation.

  4. Code review for backup manifest.

  5. Document the backup manifest file format.

  6. Fix typo in pg_validatebackup documentation.

  7. Exclude backup_manifest file that existed in database, from BASE_BACKUP.

  8. Msys2 tweaks for pg_validatebackup corruption test

  9. Fix resource management bug with replication=database.

  10. Be more careful about time_t vs. pg_time_t in basebackup.c.

  11. pg_validatebackup: Fix 'make clean' to remove tmp_check.

  12. pg_validatebackup: Also use perl2host in TAP tests.

  13. Generate backup manifests for base backups, and validate them.

  14. Add checksum helper functions.

  15. pg_waldump: Add a --quiet option.

  16. Catversion bump for b9b408c48724

  17. pg_basebackup: Refactor code for reading COPY and tar data.

  18. Use a ResourceOwner to track buffer pins in all cases.

  19. Use ARMv8 CRC instructions where available.

  20. Logical replication support for initial data copy

  21. Use Intel SSE 4.2 CRC instructions where available.

  22. Switch to CRC-32C in WAL and other places.

  23. Remove support for 64-bit CRC.

  24. Change CRCs in WAL records from 64bit to 32bit for performance reasons.

On Fri, Mar 27, 2020 at 4:02 PM David Steele <david@pgmasters.net> wrote:
> I prefer to validate the size and checksum in the same pass, but I'm not
> sure it's that big a deal.  If the backup is being corrupted under the
> validate process that would also apply to files that had already been
> validated.

I did it like this because I thought that in typical scenarios it
would be likely to produce useful results more quickly. For instance,
suppose that you forget to restore the tablespace directories, and
just get the main $PGDATA directory. Well, if you do it all in one
pass, you might spend a long time checksumming things before you
realize that some files are completely missing. I thought it would be
useful to complain about files that are extra or missing or the wrong
size FIRST, because that only requires us to stat() each file, and
only after that do the comparatively extensive checksumming step that
requires us to read the entire contents of each file. Granted, unless
you use --exit-on-error, you're going to get all the complaints
eventually anyway, but you might use that option, or you might hit ^C
when you start to see a slough of complaints poppoing out.

Maybe that was the wrong idea, but I thought people would like the
idea of running cheaper checks first. I wasn't worried about
concurrent modification of the backup because then you're super-hosed
no matter what.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company