Re: Add LZ4 compression in pg_dump

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>
To: Georgios <gkokolatos@protonmail.com>
Cc: pgsql-hackers@lists.postgresql.org, Rachel Heaton <rachelmheaton@gmail.com>
Date: 2022-03-26T18:33:36Z
Lists: pgsql-hackers
On Sat, Mar 26, 2022 at 11:21:56AM -0500, Justin Pryzby wrote:
> You're passing both the compression method *and* level.  I think there should
> be a structure which includes both.  In the future, that can also handle
> additional options.

I'm not sure if there's anything worth saving, but I did that last year with
0003-Support-multiple-compression-algs-levels-opts.patch
I sent a rebased copy off-list.
https://www.postgresql.org/message-id/flat/20210104025321.GA9712@telsasoft.com#ca1b9f9d3552c87fa874731cad9d8391

|	fatal("not built with LZ4 support");
|	fatal("not built with lz4 support");

Please use consistent capitalization of "lz4" - then the compiler can optimize
away duplicate strings.

> 0004: The include should use <lz4.h> and not "lz4.h"

Also, use USE_LZ4 rather than HAVE_LIBLZ4, per 75eae0908.



Commits

  1. Advance input pointer when LZ4 compressing data

  2. Null-terminate the output buffer of LZ4Stream_gets

  3. Rework code defining default compression for dir/custom formats in pg_dump

  4. pg_dump: Use only LZ4 frame format for compression

  5. Minor comment improvements for compress_lz4

  6. Unify buffer sizes in pg_dump compression API

  7. Improve type handling in pg_dump's compress file API

  8. Improve wording in pg_dump compression docs

  9. Fix condition in pg_dump TAP test

  10. Add LZ4 compression to pg_dump

  11. Introduce a generic pg_dump compression API

  12. Prepare pg_dump internals for additional compression methods

  13. Fix behavior with pg_restore -l and compressed dumps

  14. Add 250c8ee07ed to git-blame-ignore-revs

  15. Provide test coverage in pg_dump for default behaviors with compression

  16. Switch pg_dump to use compression specifications

  17. Refactor code parsing compression option values (-Z/--compress)

  18. meson: Add some missing env settings for tests of pg_dump and pg_verifybackup

  19. Extend TAP tests of pg_dump to test for compression with gzip

  20. Clean up some dead code in pg_dump with tar format and gzip compression

  21. Add TAP test in pg_dump with --format=tar and --compress

  22. Replace BASE_BACKUP COMPRESSION_LEVEL option with COMPRESSION_DETAIL.

  23. Refactor the pg_dump zlib code from pg_backup_custom.c to a separate file,