Horton

Re: backup manifests

Stephen Frost <sfrost@snowman.net>

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From: Stephen Frost <sfrost@snowman.net>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, David Fetter <david@fetter.org>, David Steele <david@pgmasters.net>, Tels <nospam-pg-abuse@bloodgate.com>, Suraj Kharage <suraj.kharage@enterprisedb.com>, Rushabh Lathia <rushabh.lathia@gmail.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: 2020-01-03T17:01:23Z
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.

Greetings,

* Robert Haas (robertmhaas@gmail.com) wrote:
> On Fri, Jan 3, 2020 at 11:44 AM Stephen Frost <sfrost@snowman.net> wrote:
> > Sure, it'd be work, and for "adding a simple backup manifest", maybe too
> > much to be worth considering ... but that's not what is going on here,
> > is it?  Are we really *just* going to add a backup manifest to
> > pg_basebackup and call it done?  That's not what I understood the goal
> > here to be but rather to start doing a lot of other things with
> > pg_basebackup beyond just having a manifest and if you think just a bit
> > farther down the path, I think you start to realize that you're going to
> > need this base set of capabilities to get to a point where pg_basebackup
> > (or whatever it ends up being called) is able to have the kind of
> > capabilities that exist in other PG backup software already.
> 
> I have no development plans for pg_basebackup that require extending
> the format of the manifest file in any significant way, and am not
> aware that anyone else has such plans either. If you are aware of
> something I'm not, or if anyone else is, it would be helpful to know
> about it.

You're certainly intending to do *something* with the manifest, and
while I appreciate that you feel you've come up with a complete use-case
that this simple manifest will be sufficient for, I frankly doubt
that'll actually be the case.  Not long ago it wasn't completely clear
that a manifest at *all* was even going to be necessary for the specific
use-case you had in mind (I'll admit I wasn't 100% sure myself at the
time either), but now that we're down the road of having one, I can't
agree with the blanket assumption that we're never going to want to
extend it, or even that it won't be necessary to add to it before this
particular use-case is fully addressed.

And the same goes for the other things that were discussed up-thread
regarding memory context and error handling and such.

I'm happy to outline the other things that one *might* want to include
in a manifest, if that would be helpful, but I'll also say that I'm not
planning to hack on adding that to pg_basebackup in the next month or
two.  Once we've actually got a manifest, if it's in an extendable
format, I could certainly see people wanting to do more with it though.

Thanks,

Stephen