Horton

Re: documenting the backup manifest file format

David Steele <david@pgmasters.net>

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From: David Steele <david@pgmasters.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Fujii Masao <masao.fujii@oss.nttdata.com>, Andrew Dunstan <andrew.dunstan@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Justin Pryzby <pryzby@telsasoft.com>, 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>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>, Jeevan Chalke <jeevan.chalke@enterprisedb.com>, vignesh C <vignesh21@gmail.com>
Date: 2020-05-15T15:05:02Z
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 5/15/20 10:17 AM, Tom Lane wrote:
> David Steele <david@pgmasters.net> writes:
>> On 5/15/20 9:34 AM, Tom Lane wrote:
>>> I vote for following the backup_label precedent; that's stood for quite
>>> some years now.
> 
>> Of course, my actual preference is to use epoch time which is easy to
>> work with and eliminates the possibility of conversion errors. It is
>> also compact.
> 
> Well, if we did that then it'd be sufficiently different from the backup
> label as to remove any risk of confusion.  But "easy to work with" is in
> the eye of the beholder; do we really want a format that's basically
> unreadable to the naked eye?

Well, I lost this argument before so it seems I'm in the minority on 
easy-to-use. We use epoch time in the pgBackRest manifests which has 
been easy to deal with in both C and Perl, so experience tells me it 
really is easy, at least for programs.

The manifest (to me, at least) is generally intended to be 
machine-processed. For instance, it contains checksums which are not all 
that useful unless they are checked programmatically -- they can't just 
be eye-balled.

Regards,
-- 
-David
david@pgmasters.net