Re: PG 15 (and to a smaller degree 14) regression due to ExprEvalStep size

Amit Langote <amitlangote09@gmail.com>

From: Amit Langote <amitlangote09@gmail.com>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: Andres Freund <andres@anarazel.de>, Andrew Dunstan <andrew@dunslane.net>, Michael Paquier <michael@paquier.xyz>, John Naylor <john.naylor@enterprisedb.com>, "Jonathan S. Katz" <jkatz@postgresql.org>, Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <dgrowleyml@gmail.com>, Peter Geoghegan <pg@bowt.ie>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Nikita Glukhov <n.gluhov@postgrespro.ru>
Date: 2022-07-22T03:21:51Z
Lists: pgsql-hackers
On Fri, Jul 22, 2022 at 2:12 AM Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
> On 2022-Jul-21, Amit Langote wrote:
>
> > Because I wrote all of it while not really understanding how the LLVM
> > constructs like blocks and branches work, the only reason I think
> > those llvm_compile_expr() additions may be correct is that all the
> > tests in jsonb_sqljson.sql pass even if I add the following line at
> > the top:
>
> I suggest to build with --enable-coverage, then run the regression tests
> and do "make coverage-html" and see if your code appears covered in the
> report.

Thanks for the suggestion.  I just did and it seems that both the
additions to ExecInterpExpr() and to llvm_compile_expr() are well
covered.

BTW, the only way I found to *forcefully* exercise llvm_compile_expr()
is to add `set jit_above_cost to 0` at the top of the test file, or
are we missing a force_jit_mode, like there is force_parallel_mode?

-- 
Thanks, Amit Langote
EDB: http://www.enterprisedb.com



Commits

  1. JSON_TABLE: Add support for NESTED paths and columns

  2. Add basic JSON_TABLE() functionality

  3. Add SQL/JSON query functions

  4. Add soft error handling to some expression nodes

  5. Adjust populate_record_field() to handle errors softly

  6. Refactor code used by jsonpath executor to fetch variables

  7. Add more SQL/JSON constructor functions

  8. SQL/JSON: support the IS JSON predicate

  9. SQL/JSON: add standard JSON constructor functions

  10. Add static assertion ensuring sizeof(ExprEvalStep) <= 64 bytes

  11. Remove size increase in ExprEvalStep caused by hashed saops

  12. pgstat: reduce timer overhead by leaving timer running.

  13. expression eval: Fix EEOP_JSON_CONSTRUCTOR and EEOP_JSONEXPR size.

  14. SQL/JSON query functions

  15. Speedup ScalarArrayOpExpr evaluation