Re: AIO v2.5

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Noah Misch <noah@leadboat.com>
Cc: pgsql-hackers@postgresql.org, Thomas Munro <thomas.munro@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Robert Haas <robertmhaas@gmail.com>, Jakub Wartak <jakub.wartak@enterprisedb.com>, Jelte Fennema-Nio <postgres@jeltef.nl>, Antonin Houska <ah@cybertec.at>
Date: 2025-03-30T23:46:57Z
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. aio: Fix assertion, clarify README

  2. aio: Fix reference to outdated name

  3. aio: Fix possible state confusions due to interrupt processing

  4. aio: Improve debug logging around waiting for IOs

  5. aio: Fix crash potential for pg_aios views due to late state update

  6. Increase BAS_BULKREAD based on effective_io_concurrency

  7. localbuf: Add Valgrind buffer access instrumentation

  8. aio: Make AIO more compatible with valgrind

  9. aio: Avoid spurious coverity warning

  10. tests: Fix incompatibility of test_aio with *_FORCE_RELEASE

  11. tests: Cope with WARNINGs during failed CREATE DB on windows

  12. aio: Add errcontext for processing I/Os for another backend

  13. aio: Add README.md explaining higher level design

  14. aio: Minor comment improvements

  15. aio: Add test_aio module

  16. aio: Add pg_aios view

  17. docs: Add acronym and glossary entries for I/O and AIO

  18. Enable IO concurrency on all systems

  19. read_stream: Introduce and use optional batchmode support

  20. docs: Reframe track_io_timing related docs as wait time

  21. bufmgr: Use AIO in StartReadBuffers()

  22. bufmgr: Implement AIO read support

  23. aio: Add WARNING result status

  24. Let caller of PageIsVerified() control ignore_checksum_failure

  25. pgstat: Allow checksum errors to be reported in critical sections

  26. Add errhint_internal()

  27. localbuf: Track pincount in BufferDesc as well

  28. aio, bufmgr: Comment fixes/improvements

  29. Fix mis-attribution of checksum failure stats to the wrong database

  30. aio: Implement support for reads in smgr/md/fd

  31. aio: Add io_method=io_uring

  32. aio: Add liburing dependency

  33. aio: Rename pgaio_io_prep_* to pgaio_io_start_*

  34. aio: Pass result of local callbacks to ->report_return

  35. aio: Be more paranoid about interrupts

  36. Redefine max_files_per_process to control additionally opened files

  37. aio: Change prefix of PgAioResultStatus values to PGAIO_RS_

  38. bufmgr: Improve stats when a buffer is read in concurrently

  39. aio: Add io_method=worker

  40. aio: Infrastructure for io_method=worker

  41. aio: Add core asynchronous I/O infrastructure

  42. aio: Basic subsystem initialization

  43. tests: Expand temp table tests to some pin related matters

  44. localbuf: Introduce FlushLocalBuffer()

  45. localbuf: Introduce TerminateLocalBufferIO()

  46. localbuf: Fix dangerous coding pattern in GetLocalVictimBuffer()

  47. localbuf: Introduce StartLocalBufferIO()

  48. localbuf: Introduce InvalidateLocalBuffer()

  49. Allow lwlocks to be disowned

  50. Make jsonb casts to scalar types translate JSON null to SQL NULL.

  51. bufmgr/smgr: Don't cross segment boundaries in StartReadBuffers()

  52. Use aux process resource owner in walsender

  53. bufmgr: Return early in ScheduleBufferTagForWriteback() if fsync=off

Hi,

On 2025-03-29 14:29:29 -0700, Noah Misch wrote:
> > Subject: [PATCH v2.14 11/29] Let caller of PageIsVerified() control
> >  ignore_checksum_failure
> > Subject: [PATCH v2.14 12/29] bufmgr: Use AIO in StartReadBuffers()
> > Subject: [PATCH v2.14 14/29] aio: Basic read_stream adjustments for real AIO
> > Subject: [PATCH v2.14 15/29] read_stream: Introduce and use optional batchmode
> >  support
> > Subject: [PATCH v2.14 16/29] docs: Reframe track_io_timing related docs as
> >  wait time
> > Subject: [PATCH v2.14 17/29] Enable IO concurrency on all systems
>
> Ready for commit

I've pushed most of these after some very light further editing.  Yay.  Thanks
a lot for all the reviews!

So far the buildfarm hasn't been complaining, but it's early days.


I didn't yet push

> > Subject: [PATCH v2.14 13/29] aio: Add README.md explaining higher level design

because I want to integrate some language that could be referenced by
smgrstartreadv() (and more in the future), as we have been talking about.


Tomorrow I'll work on sending out a new version with the remaining patches. I
plan for that version to have:

- pg_aios view with the security checks (already done, trivial)

- a commit with updated language for smgrstartreadv(), probably referencing
  aio's README

- a change to mdreadv() around zero_damaged_pages, as Noah and I have been
  discussing

- updated tests, with the FIXMEs etc addressed

- a reviewed version of the errcontext callback patch that Melanie sent
  earlier today


Todo beyond that:

- The comment and docs updates we've been discussing in
  https://postgr.es/m/5fc6r4smanncsmqw7ib6s3uj6eoiqoioxbd5ibmhtqimcggtoe%40fyrok2gozsoq

- I think a good long search through the docs is in order, there probably are
  other things that should be updated, beyond concrete references to
  effective_io_concurrency etc.

- Whether we should do something, and if so what, about BAS_BULKREAD for
  18. Thomas may have some thoughts / code.

- Whether there's anything committable around Jelte's RLIMIT_NOFILE changes.


Greetings,

Andres Freund