Horton

Re: WAL logging problem in 9.4.3?

Alvaro Herrera <alvherre@2ndquadrant.com>

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From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Cc: michael.paquier@gmail.com, david@pgmasters.net, hlinnaka@iki.fi, simon@2ndquadrant.com, tgl@sss.pgh.pa.us, andres@anarazel.de, masao.fujii@gmail.com, kleptog@svana.org, pgsql-hackers@postgresql.org
Date: 2017-04-07T23:42:17Z
Lists: pgsql-hackers 
Alvaro Herrera wrote:

> I suppose the rationale is that this shouldn't happen because any
> operation that does things this way must hold an exclusive lock on the
> relation.  But that doesn't guarantee that the relcache entry is
> completely stable, does it?  If we can get proof of that, then this
> technique should be safe, I think.

It occurs to me that in order to test this we could run the recovery
tests (including Michael's new 006 file, which you didn't include in
your patch) under -D CLOBBER_CACHE_ALWAYS.  I think that'd be sufficient
proof that it is solid.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Add perl2host call missing from a new test file.

  2. Skip WAL for new relfilenodes, under wal_level=minimal.

  3. Revert "Skip WAL for new relfilenodes, under wal_level=minimal."

  4. Back-patch log_newpage_range().

  5. During heap rebuild, lock any TOAST index until end of transaction.

  6. In log_newpage_range(), heed forkNum and page_std arguments.

  7. Back-patch src/test/recovery and PostgresNode from 9.6 to 9.5.

  8. Reduce pg_ctl's reaction time when waiting for postmaster start/stop.

  9. Accelerate end-of-transaction dropping of relations

  10. Redesign the planner's handling of index-descent cost estimation.

  11. Make TRUNCATE do truncate-in-place when processing a relation that was created