Horton

Re: [HACKERS] Custom compression methods (mac+lz4.h)

Justin Pryzby <pryzby@telsasoft.com>

View thread View on postgr.es
From: Justin Pryzby <pryzby@telsasoft.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Andres Freund <andres@anarazel.de>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Alexander Korotkov <a.korotkov@postgrespro.ru>, David Steele <david@pgmasters.net>, Ildus Kurbangaliev <i.kurbangaliev@gmail.com>, Dmitry Dolgov <9erthalion6@gmail.com>, Andrey Borodin <x4mmm@yandex-team.ru>, pgsql-hackers@lists.postgresql.org
Date: 2021-03-20T23:19:57Z
Lists: pgsql-hackers 
On Sat, Mar 20, 2021 at 05:37:07PM -0400, Tom Lane wrote:
> Justin Pryzby <pryzby@telsasoft.com> writes:
> > On Fri, Mar 19, 2021 at 02:07:31PM -0400, Robert Haas wrote:
> >> On Fri, Mar 19, 2021 at 1:44 PM Justin Pryzby <pryzby@telsasoft.com> wrote:
> >>> configure: WARNING: lz4.h: accepted by the compiler, rejected by the preprocessor!
> >>> configure: WARNING: lz4.h: proceeding with the compiler's result
> 
> >> No, I don't see this. I wonder whether this could possibly be an
> >> installation issue on Andrey's machine? If not, it must be
> >> version-dependent or installation-dependent in some way.
> 
> > Andrey, can you check if latest HEAD (bbe0a81db) has these ./configure warnings ?
> 
> FWIW, I also saw that, when building HEAD against MacPorts' version
> of liblz4 on an M1 Mac.  config.log has
...
> Digging around, it looks like the "-I/opt/local/include" bit came
> from LZ4_CFLAGS, which we then stuck into CFLAGS, but it needed
> to be put in CPPFLAGS in order to make this test work.

If it's the same as the issue Andrey reported, then it causes a ./configure
WARNING, which is resolved by the ac_save hack, which I copied from ICU.

I'll shortly send a patchset including my tentative fix for that.

The configure.ac bits are also on this other thread:
https://www.postgresql.org/message-id/20210315180918.GW29463%40telsasoft.com
0005-re-add-wal_compression_method-lz4.patch 

+if test "$with_lz4" = yes; then
+  ac_save_CPPFLAGS=$CPPFLAGS
+  CPPFLAGS="$LZ4_CFLAGS $CPPFLAGS"
+
+  # Verify we have LZ4's header files
+  AC_CHECK_HEADERS(lz4/lz4.h, [],
+       [AC_CHECK_HEADERS(lz4.h, [], [AC_MSG_ERROR([lz4.h header file is required for LZ4])])])
+
+  CPPFLAGS=$ac_save_CPPFLAGS
+fi

-- 
Justin

Commits

  1. docs: Update TOAST storage docs for configurable compression.

  2. Further tweaking of pg_dump's handling of default_toast_compression.

  3. Fix interaction of TOAST compression with expression indexes.

  4. Tidy up more loose ends related to configurable TOAST compression.

  5. Short-circuit slice requests that are for more than the object's size.

  6. Mostly-cosmetic adjustments of TOAST-related macros.

  7. Remove useless configure probe for <lz4/lz4.h>.

  8. Error on invalid TOAST compression in CREATE or ALTER TABLE.

  9. docs: Fix omissions related to configurable TOAST compression.

  10. More code cleanup for configurable TOAST compression.

  11. Bring configure support for LZ4 up to snuff.

  12. Make compression.sql regression test independent of default.

  13. Use valid compression method in brin_form_tuple

  14. Fix up pg_dump's handling of per-attribute compression options.

  15. Allow configurable LZ4 TOAST compression.

  16. Fix inconsistencies in the code

  17. Mostly-cosmetic improvements in memory chunk header alignment coding.

  18. Allow numeric to use a more compact, 2-byte header in many cases.