Horton

Re: [PING] [PATCH v2] parallel pg_restore: avoid disk seeks when jumping short distance forward

Dimitrios Apostolou <jimis@gmx.net>

View thread View on postgr.es
From: Dimitrios Apostolou <jimis@gmx.net>
To: Tom Lane <tgl@sss.pgh.pa.us>, Dimitrios Apostolou <jimis@gmx.net>
Cc: Chao Li <li.evan.chao@gmail.com>, Nathan Bossart <nathandbossart@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, pgsql-hackers@lists.postgresql.org
Date: 2025-10-16T18:59:05Z
Lists: pgsql-hackers 
Thank you for your work on this, Tom.
I'll try to test it in the weekend. 

Dimitris

On 16 October 2025 19:01:10 CEST, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>I wrote:
>> I think this is more or less committable, and then we could get
>> back to the original question of whether it's worth tweaking
>> pg_restore's seek-vs-scan behavior.
>
>And done.  Dimitrios, could you re-do your testing against current
>HEAD, and see if there's still a benefit to tweaking pg_restore's
>seek-vs-read decisions, and if so what's the best number?
>
>			regards, tom lane

Commits

  1. Avoid short seeks in pg_restore.

  2. Don't rely on zlib's gzgetc() macro.

  3. Add more TAP test coverage for pg_dump.

  4. Split 002_pg_dump.pl into two test files.

  5. Align the data block sizes of pg_dump's various compression modes.

  6. Fix serious performance problems in LZ4Stream_read_internal.

  7. Fix poor buffering logic in pg_dump's lz4 and zstd compression code.

  8. Fix issue with reading zero bytes in Gzip_read.

  9. Restore test coverage of LZ4Stream_gets().