Upstream PR 2995 Occlusion Queries

Upstream PR #2995 — Keep occlusion queries inside render passes

Upstream work · Actionable research · Research and retired work

Current disposition — November 1, 2026

Reviewed: November 1, 2026. Fork source: b7140848 (full SHA b71408480a3a979a9c584663e1d1f400904c8bb7). Latest stable checked: v0.8.136-0-g458730bf5373, September 30, source 458730bf5373f1f0d027450fef7443e3af7a3ae1. GitHub state, branch recommendation, source presence and release availability are separate facts. See current status and release versus main.

Current field	November 1, 2026 observation
GitHub source	Upstream #2995
GitHub state / draft	Open / No
Current head	42cf316e59b01aaa2de564cca036668eef1177e7
Originally reviewed head	Not recorded on original page
Last metadata update (UTC)	2026-10-18T20:59:11Z
Head versus original review	Original page did not record a head; code-change comparison is not established.
Current action	Preserve opportunity; reopen only for an affected workload.
Fork/release availability	Fork #318 is unmerged and absent from pinned main/stable; upstream’s open PR is not a release promise.

Upstream remains open. Fork #318 is now closed without merge and SKIPPED/HOLD for the current Deck effort. One fresh pair retained +2.305% guest cadence, essentially unchanged CPU and mixed tails, including a worse isolated maximum. It establishes an opportunity, not a qualified broad gain or zero benefit. Native query semantics and required XISO timings remain missing.

This refresh checked GitHub identity/state and the specific source boundaries named above. It did not rerun native games, XISO timings or integration qualification. Historical performance claims remain attached to their original heads.

Historical review — September 21, 2026

The review below is preserved as written, including its original state, head, fork baseline and proposed handoff. Its present-tense statements apply to that dated review; the current disposition above governs today’s action.

← Upstream Work In Need

Field	Value
Upstream PR	xemu-project/xemu#2995
Audit state	Candidate for fork rework; refresh before implementation
Fork baseline reviewed	82d04d84bdb3de956f20c3537e1da2cece0e8da2
Priority	First Vulkan performance experiment
Upstream contact	No comment posted by this audit

Candidate

Reset query pools before render-pass work where possible, leaving query begin and end inside the pass. Preserve the renderer's report lifecycle, including segment accumulation and every path that ends a pass.

Required proof

• Force a tiny pool: capacity pressure retires work or follows another bounded policy without aborting.
• A report split by a pass transition has the same guest-visible result.
• Exercise clears, target changes, transient-buffer rollover, and growth.
• Measure pass breaks, resets, segments, submissions, GPU duration, and guest-progress tails on one deterministic query-heavy scene.

The upstream Raspberry Pi measurement is motivation only; it predicts neither performance nor correctness on other devices.

References

• Upstream PR #2995
• Upstream Work In Need
• Vulkan Performance