[williamrobertson13]

Summary

Fix a memory leak in Pool.makeWithTTL with the usage strategy. Retired resources and consumed acquisition errors could remain in the TTL queue when the pool reached its target or minimum size.

The usage strategy no longer keeps its own queue of items. state.items is a Set, which iterates in insertion order, so the strategy retires the oldest non-invalidated entry of state.items directly and reclaim moves a reclaimed item to the back by re-adding it. Nothing outside the pool's own state references an item, so it is released the moment it leaves the pool, whether by invalidation, a consumed acquisition failure, or shutdown. The pool core no longer contains any strategy-specific hooks; its only change is skipping onAcquire for a failed acquisition that a borrower consumed while it was finalizing. Public types, last-lease finalization, FIFO retirement, and minimum-size behavior are preserved. Each retirement skips over invalidated busy items ahead of it in insertion order, which is the one cost of not keeping a separate list.

Tests cover four GC retention cases, last-lease finalization, and FIFO/minimum-size behavior after head, middle, or tail removal. Pool and McpServer tests share a GC helper; GC cases are skipped on Bun and Deno. Includes an effect patch changeset.

Validation

Validation on implementation commit 6c79fc749f:

• Pool suite: 46 passed, including all four GC regressions.
• McpServer suite: 69 passed.
• pnpm lint and GOMEMLIMIT=4GiB GOMAXPROCS=4 pnpm check passed.

Earlier failing-before verification substituted pre-fix Pool.ts from 3d59ae6d5f: all four GC regressions failed and the other 39 Pool tests passed. With no strategy-owned queue there is no enqueue-after-removal window left to cover.

Toolchain commands ran through nix develop -c.

Closes EFF-1425

[changeset-bot]

🦋 Changeset detected

Latest commit: 93c2efc

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 31 packages

Name	Type
effect	Patch
@effect/opentelemetry	Patch
@effect/vitest	Patch
@effect/ai-anthropic	Patch
@effect/ai-openai-compat	Patch
@effect/ai-openai	Patch
@effect/ai-openrouter	Patch
@effect/ai-typesafe	Patch
@effect/atom-react	Patch
@effect/atom-solid	Patch
@effect/atom-vue	Patch
@effect/platform-browser	Patch
@effect/platform-bun	Patch
@effect/platform-deno	Patch
@effect/platform-node-shared	Patch
@effect/platform-node	Patch
@effect/sql-clickhouse	Patch
@effect/sql-d1	Patch
@effect/sql-libsql	Patch
@effect/sql-mssql	Patch
@effect/sql-mysql2	Patch
@effect/sql-pg	Patch
@effect/sql-pglite	Patch
@effect/sql-sqlite-bun	Patch
@effect/sql-sqlite-do	Patch
@effect/sql-sqlite-node	Patch
@effect/sql-sqlite-react-native	Patch
@effect/sql-sqlite-wasm	Patch
@effect/docgen	Patch
@effect/doctest	Patch
@effect/openapi-generator	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

Bundle Size Analysis

Generated from PR build output; treat the content below as untrusted.

File Name	Current Size	Previous Size	Difference
arbitrary-combinators.ts	37.71 KB	37.71 KB	0.00 KB (0.00%)
basic.ts	6.87 KB	6.87 KB	0.00 KB (0.00%)
batching.ts	9.95 KB	9.95 KB	0.00 KB (0.00%)
brand.ts	6.45 KB	6.45 KB	0.00 KB (0.00%)
cache.ts	10.77 KB	10.77 KB	0.00 KB (0.00%)
config.ts	21.83 KB	21.83 KB	0.00 KB (0.00%)
differ.ts	20.67 KB	20.67 KB	0.00 KB (0.00%)
http-client.ts	21.94 KB	21.94 KB	0.00 KB (0.00%)
http-router.ts	36.96 KB	36.96 KB	0.00 KB (0.00%)
logger.ts	10.88 KB	10.88 KB	0.00 KB (0.00%)
metric.ts	9.02 KB	9.02 KB	0.00 KB (0.00%)
optic.ts	6.70 KB	6.70 KB	0.00 KB (0.00%)
pubsub.ts	15.10 KB	15.10 KB	0.00 KB (0.00%)
queue.ts	11.85 KB	11.85 KB	0.00 KB (0.00%)
schedule.ts	10.96 KB	10.96 KB	0.00 KB (0.00%)
schema-bigdecimal.ts	13.40 KB	13.40 KB	0.00 KB (0.00%)
schema-binary.ts	39.82 KB	39.82 KB	0.00 KB (0.00%)
schema-class.ts	20.38 KB	20.38 KB	0.00 KB (0.00%)
schema-fromJsonSchemaDocument.ts	31.18 KB	31.18 KB	0.00 KB (0.00%)
schema-representation-roundtrip.ts	26.60 KB	26.60 KB	0.00 KB (0.00%)
schema-string-transformation.ts	13.96 KB	13.96 KB	0.00 KB (0.00%)
schema-string.ts	11.55 KB	11.55 KB	0.00 KB (0.00%)
schema-template-literal.ts	15.70 KB	15.70 KB	0.00 KB (0.00%)
schema-toArbitrary.ts	37.24 KB	37.24 KB	0.00 KB (0.00%)
schema-toCodeDocument.ts	24.84 KB	24.84 KB	0.00 KB (0.00%)
schema-toCodecJson.ts	19.61 KB	19.61 KB	0.00 KB (0.00%)
schema-toEquivalence.ts	19.75 KB	19.75 KB	0.00 KB (0.00%)
schema-toFormatter.ts	19.85 KB	19.85 KB	0.00 KB (0.00%)
schema-toJsonSchemaDocument.ts	24.15 KB	24.15 KB	0.00 KB (0.00%)
schema-toRepresentation.ts	19.89 KB	19.89 KB	0.00 KB (0.00%)
schema.ts	19.59 KB	19.59 KB	0.00 KB (0.00%)
stm.ts	12.80 KB	12.80 KB	0.00 KB (0.00%)
stream.ts	9.83 KB	9.83 KB	0.00 KB (0.00%)

[williamrobertson13]

thanks so much for fixing this up (and apologies for the slop PR submission)!