Horton

Re: refactoring basebackup.c

Dipesh Pandit <dipesh.pandit@gmail.com>

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From: Dipesh Pandit <dipesh.pandit@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andrew Dunstan <andrew@dunslane.net>, tushar <tushar.ahuja@enterprisedb.com>, Michael Paquier <michael@paquier.xyz>, Jeevan Ladhe <jeevan.ladhe@enterprisedb.com>, Dmitry Dolgov <9erthalion6@gmail.com>, Mark Dilger <mark.dilger@enterprisedb.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2022-01-28T08:54:38Z
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. Document BaseBackupSync and BaseBackupWrite wait events.

  2. Support long distance matching for zstd compression

  3. Fix possible NULL-pointer-deference in backup_compression.c.

  4. Allow parallel zstd compression when taking a base backup.

  5. Make PostgreSQL::Test::Cluster::run_log() return a useful value.

  6. Fix a few goofs in new backup compression code.

  7. Replace BASE_BACKUP COMPRESSION_LEVEL option with COMPRESSION_DETAIL.

  8. Add 'basebackup_to_shell' contrib module.

  9. Allow extensions to add new backup targets.

  10. Change HAVE_LIBLZ4 and HAVE_LIBZSTD tests to USE_LZ4 and USE_ZSTD.

  11. pg_basebackup: Clean up some bogus file extension tests.

  12. pg_basebackup: Avoid unclean failure with server-compression and -D -.

  13. Fix LZ4 tests for remaining buffer space.

  14. Add support for zstd base backup compression.

  15. pg_basebackup: Allow client-side LZ4 (de)compression.

  16. Add suport for server-side LZ4 base backup compression.

  17. Add min() and max() aggregates for xid8.

  18. Remove superfluous variable.

  19. pg_basebackup: Cleaner handling when compression is multiply specified.

  20. Allow server-side compression to be used with -Fp.

  21. pg_basebackup: Fix a couple of recently-introduced bugs.

  22. Tidy up a few cosmetic issues related to pg_basebackup.

  23. Server-side gzip compression.

  24. Unbreak pg_basebackup/t/010_pg_basebackup.pl on msys

  25. Suppress variable-set-but-not-used warning from clang 13.

  26. Extend the options of pg_basebackup to control compression

  27. Support base backup targets.

  28. Modify pg_basebackup to use a new COPY subprotocol for base backups.

  29. Document that tar archives are now properly terminated.

  30. Fix thinko in bbsink_throttle_manifest_contents.

  31. Have the server properly terminate tar archives.

  32. Minimal fix for unterminated tar archive problem.

  33. Introduce 'bbstreamer' abstraction to modularize pg_basebackup.

  34. Introduce 'bbsink' abstraction to modularize base backup code.

  35. Refactor basebackup.c's _tarWriteDir() function.

  36. Flexible options for CREATE_REPLICATION_SLOT.

  37. Flexible options for BASE_BACKUP.

Attachments

Hi,

> I made a pass over these patches today and made a bunch of minor
> corrections. New version attached. The two biggest things I changed
> are (1) s/gzip_extractor/gzip_compressor/, because I feel like you
> extract an archive like a tarfile, but that is not what is happening
> here, this is not an archive and (2) I took a few bits of out of the
> test case that didn't seem to be necessary. There wasn't any reason
> that I could see why testing for PG_VERSION needed to be skipped when
> the compression method is 'none', so my first thought was to just take
> out the 'if' statement around that, but then after more thought that
> test and the one for pg_verifybackup are certainly going to fail if
> those files are not present, so why have an extra test? It might make
> sense if we were only conditionally able to run pg_verifybackup and
> wanted to have some test coverage even when we can't, but that's not
> the case here, so I see no point.

Thanks. This makes sense.

+#ifdef HAVE_LIBZ
+   /*
+    * If the user has requested a server compressed archive along with
archive
+    * extraction at client then we need to decompress it.
+    */
+   if (format == 'p' && compressmethod == COMPRESSION_GZIP &&
+           compressloc == COMPRESS_LOCATION_SERVER)
+       streamer = bbstreamer_gzip_decompressor_new(streamer);
+#endif

I think it is not required to have HAVE_LIBZ check in pg_basebackup.c
while creating a new gzip writer/decompressor. This check is already
in place in bbstreamer_gzip_writer_new() and
bbstreamer_gzip_decompressor_new()
and it throws an error in case the build does not have required library
support. I have removed this check from pg_basebackup.c and updated
a delta patch. The patch can be applied on v5 patch.

Thanks,
Dipesh