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From: "davecramer (@davecramer)" <noreply+davecramer@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Tue, 24 Feb 2026 16:44:59 +0000
Subject: Re: [pgjdbc/pgjdbc] PR #3895: implement require_auth, this is pretty much how libpq does this. 
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> Why [3fab588](https://github.com/pgjdbc/pgjdbc/commit/3fab588d93ae4cfeb13f75ba08894b804b256d51) is the first bad commit
> 
> The commit does two things:
> 
> 1. Adds `autosave=always` to the CI test matrix
>    Before this commit, tests never ran with autosave=always.
>    The unlucky random combination assigned autosave=always to the PG 9.1 job.
> 2. Changes shouldCreateAutomaticSavepoint() to create more savepoints
> 
> The old code checked isTransactionActive() before checking AutoSave.NEVER, meaning it would bail out early in some cases. The new code reorders the checks and also expands isSpecialQuery() — but the net effect is that with autosave=always, every non-special statement now gets wrapped in SAVEPOINT / RELEASE SAVEPOINT.
> 
> The combined effect
> 
> DatabaseEncodingTest.encoding() does ~11,100 INSERTs in one transaction. With autosave=always, each INSERT creates a subtransaction. PG 9.1's default max_locks_per_transaction=64 gives only ~6,400 lock table slots — far fewer than the ~11,100 needed.
> 
> Frankly, I think the test did the right thing: it identified a bug.
> 
> Then we could have several workarounds:
> 
> 1. Try if increase max_locks_per_transaction in the CI PostgreSQL 9.1 config helps (e.g., -c max_locks_per_transaction=256 in entrypoint.sh).
> 2. Exclude autosave=always from PG 9.1 in the matrix — add a rule like:
>    `matrix.imply({pg_version: '9.1'}, {autosave: {value: 'never'}});`
> 3. Add periodic commits in `DatabaseEncodingTest` to keep subtransaction count manageable
> 
> I am leaning towards 1 or 2.

easy enough to try 1 in the PR.