WIP: fix(macos): hold MoltenVK's giant compiles behind the game until its first frame, at a lower QoS class #665

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Type: fix · Risk: medium · Tested on: macOS 26.7.1, Apple M4 Max (MoltenVK 1.4.2), arm64 and x86_64 under Rosetta · Needs: macOS, Apple silicon (a start on the rebased stack); Windows and Linux, any GPU (build and start)

Why

On a Mac the game's first frame could wait minutes after the precompile had let it start. Metal's compiler service has a
fixed number of connections (16 on an M4 Max), and the precompile's workers kept giant compute compiles running on all of
them behind the game. The driver compiles a small blit program inside the game thread's first submit, and that request had
to wait for a giant on its connection to end: in start 17 the game thread sat in _dispatch_sync_f_slow behind 16 giant
compiles, and the first frame came only after the compiler service crashed under them, about 3 minutes after the hand-off.
A giant whose compile failed that way was also compiled again at once among the other giants, where it failed again. This PR
keeps the precompile's giants from starting behind the game until the game has shown its first frame, builds the giants and
everything behind the game at a lower QoS class than the game's threads, and tries a failed giant again alone. It is part of
the macOS port. See #420.

How to reproduce

Seen on: macOS 26.7.1, Apple M4 Max, MoltenVK 1.4.2 (main does not run on macOS yet: seen on the macOS port's integration
build 4e472987, which carries the open macOS PRs)
Settings and switches: defaults (start mode), the program cache carried from earlier starts
Steps: start the game and wait for the title after the precompile's hand-off.
Expected: the first frame a few seconds after the hand-off.
Actual: start 17: the first frame came after the burst in which every giant still in flight failed
(XPC_ERROR_CONNECTION_INTERRUPTED … after multiple retries), about 188-198 s after the hand-off; a sample at 08:25 had the
game thread in tryBoost → _dispatch_sync_f_slow and 16 compiler connection threads each in a synchronous send
(reports/2026-11-14-mac-startup-17.md; analysis in reports/2026-11-14-title-stall.md §1-§2).

What changed

Under compiler_service (MoltenVK only, #652), behind the game no compile of more than RX_VK_GIANT_WORDS starts until the
game has shown RX_VK_GIANT_HOLD_PRESENTS (1) frames since the hand-off, or for RX_VK_GIANT_HOLD_S (120) s at most; the
giants in flight at the hand-off finish, the held ones are deferred and built after it, never dropped. The precompile's workers
build every giant, and everything behind the game, at QoS class utility (RX_VK_COMPILE_QOS); the rest, which the title
waits for, keep the thread's own class. A giant compile that fails is not tried again at once among the other giants: its place
is given back and it is compiled once more alone, with a new pipeline cache, once no other giant is in flight and none starts
meanwhile. Every other driver is unchanged.

• gpu/vk/precompile_handoff.h (no Vulkan): giant_hold_presents/giant_hold_s, Giants::hold/release/held (the hold
  in the gate), compile_qos and qos_for (which class a run is built at), ThreadQos (a worker's class, changed only when it
  must), Retry (Now, Later, Fresh) and Giants::solo_ask/solo/solo_end/solo_cancel (one giant alone, in turn).
• gpu/vk/vk_draw.cpp precompile_run: the hold set at the hand-off and released by the presents counter or the time, one
  line when the giants go on; behind_worker takes the class for each run (compile_qos_apply: pthread_set_qos_class_self_np
  on macOS, nothing elsewhere); its compute arm marks a giant's compile Retry::Later and, when it failed, calls
  compute_alone; create_watched's second try honours compile_retry.
• docs/development.md: rows for RX_VK_GIANT_HOLD_PRESENTS/RX_VK_GIANT_HOLD_S and RX_VK_COMPILE_QOS; the
  RX_VK_COMPILER_SERVICE row names the retry alone.
• tests: tests/precompile_handoff_test.cpp (the hold behind the game, the QoS choice, one giant alone at a time) and
  tests/test_precompile_handoff.py (the wiring; on macOS vk_draw.cpp's own compile_qos_apply on a real thread, which
  shows that MoltenVK's way of asking for a compile, a block dispatched to the default global queue, runs at the worker's
  class).

Measurements

Verdict: works as designed in the game, but its own gain is not measured: on the integration builds that carry it the hold
held the giants until the first frame (start 21: 143 deferred, released 27.0 s after the game started, 1,183 frames shown;
start 24: 212 deferred, released after 46.2 s) and the first frame came 4.5-5.0 s after the hand-off (starts 21-24). Starts 18
and 19, with #664's bound but without this PR, also had their first frame 4.6 and 4.5 s after the hand-off, and the
game-free probe TS-02 did not reproduce the wait (its blit program came from Metal's cache in 0.77 ms under 16 compiles). So
this PR removes the wait's cause (no giant starts while the game has shown nothing) without a measured before/after of its
own. No giant failed in starts 21-24, so the retry alone did not run.

Baseline: main does not run on macOS yet, so the columns are the macOS port's integration builds, arm64, MoltenVK 1.4.2, start
mode. Before: 4e472987 (start 17: no bound, no hold). After: 09f9a171 (start 21, Integration 28, which carries this topic and
#666). One run each.

Hardware: macOS 26.7.1, Apple M4 Max (40-core GPU), MoltenVK 1.4.2, 16-core CPU, 64 GB
Scene: a start to the title, windowless, defaults
Method: the game log's hand-off line, the hold lines and the first vk: present texture … rendered line, one run each; the
probe TS-02 (reports/TitleStall-files/ts02/run-01-arm64/, summary.json 53fddf57…)
How to reproduce: a start of a macOS build from a seeded cache; RX_VK_GIANT_HOLD_PRESENTS=0 turns the hold off

	Before: integration @ 4e472987 (start 17)	After: integration @ 09f9a171 (start 21)
giants in flight at the hand-off	16 (no bound)	4 at most before, 3 behind the game
giants started behind the game before the first frame	not held	none (143 deferred until the first frame)
hand-off → first frame	about 188-198 s [inferred from the log, §1 of the report]	5.0 s
compiler-service crashes	13	6

#21: vk: precompile: behind the game, no giant compile starts until the game has shown 1 frames (0: none waits), 120 s at most (RX_VK_GIANT_HOLD_PRESENTS, RX_VK_GIANT_HOLD_S); the workers build the giants, and everything behind the game, at QoS class utility (RX_VK_COMPILE_QOS)
#21: vk: precompile: behind the game: giant compiles go on, 27.0 s after the game started, which has shown 1183 frames since (they waited for 1; 143 deferred until then; RX_VK_GIANT_HOLD_PRESENTS, RX_VK_GIANT_HOLD_S)
#24: vk: precompile: behind the game: giant compiles go on, 46.2 s after the game started, which has shown 1837 frames since (they waited for 1; 212 deferred until then; …)

Run reports: reports/2026-11-14-mac-startup-17.md, -18.md, -19.md, -21.md, -22.md, -24.md; the analysis and
TS-01/TS-02: reports/2026-11-14-title-stall.md.

Flags and settings

Three new switches, read only with RX_VK_COMPILER_SERVICE (MoltenVK); nothing changes elsewhere.

Flag	What it is	Before this PR	After this PR	Effect	Helps / doesn't help / untested	Recommendation
RX_VK_GIANT_HOLD_PRESENTS	frames the game must show after the hand-off before a giant starts behind it; 0: no hold	(no switch)	1	the game's first submit finds the compiler's connections free of new giants	helps: MoltenVK (starts 21-24, the hold seen); untested: other values	as it ships
RX_VK_GIANT_HOLD_S	the hold's longest time, so a start that shows no frame still builds them	(no switch)	120	bounds the hold	untested beyond the default	as it ships
RX_VK_COMPILE_QOS	utility, background or default: the class giants and work behind the game are built at	(no switch)	utility	Metal serves the game's own compile requests first	helps: shown on a real thread (the test); untested in the game against default	as it ships

Testing

Tested: on macOS 26.7.1, Apple M4 Max, at this head (main 6c9edffe plus #650, #651, #652, #664 and this PR):

• tests/test_precompile_handoff.py --arch arm64 and --arch x86_64 (the fixtures run under Rosetta): pass on both (the hold,
  the QoS choice and fixture, the retry alone, and every earlier check). On this branch's base (#664 20367871) with
  the test files copied in (sha256 in ts-test-files.sha256): fails on both, the fixture does not build and the source checks
  name what is missing (precompile_run lacks: … giant_hold_presents …, … compile_qos …)
  (reports/PubWave-files/PubLate1/tsls-proof-01/ts-*).
• tests/test_warm_handoff.py --arch arm64 still passes (tsls-proof-01/ts-warm-arm64).
• Every check that reads a renderer file changed by #650, #651, #652, #664 or this PR, and the new ones (301 names,
  299 checks on this branch), through tools/ls-suite.py: 279 pass, 20 fail. 19 are the same 19 as at #652's head (16 also fail on main 6c9edffe on macOS;
  3 are skipped on macOS in a full run and fail only because named); the 20th is test_gpu_hang_watch ("exit 3, 3.5 s" against
  its 3.4 s bound, at load 44-50), the suite's known load-sensitive timing test, which reads no file this PR changes
  (title-stall-related-01/, title-stall-related-01-compare.txt).
• gpu/vk/vk_draw.cpp compiled whole for arm64 and x86_64 with main's renderer flags (with #476's and #492's macOS compile pieces
  in a scratch tree): both objects made, exit 0 (reports/PubWave-files/PubLate1/compile/title-stall/).
• Off Apple (unifdef -U__APPLE__, base against head): precompile_handoff.h and vk_draw.cpp differ: the header's new
  pieces; in vk_draw.cpp compile_qos_apply's off-Apple body ((void)q;), the thread-local compile_retry and
  compile_failed_later, and create_watched's second try and line reading compile_retry, which is Now there (only
  behind_worker, under compiler_service, sets another), so create_watched (reached off Apple only with
  RX_VK_SLOW_COMPILE_S set) tries again and logs as before (reports/PubWave-files/PubLate1/offapple-title-stall.txt).
• In the game (integration builds carrying these commits, before the rebase): starts 21-24, above.

Not tested: the game at this head (main does not run on macOS without the other macOS PRs); the retry alone in the game (no
giant failed in starts 21-24); the QoS class's effect in the game against RX_VK_COMPILE_QOS=default; Windows and Linux (the
new code runs only under compiler_service, off there; it is compiled there): not built on Windows or Linux; its test request
covers it.

Must be tested:

• macOS, Apple silicon, on the rebased macOS stack: a start from a seeded cache, expecting the hold line at the hand-off, giant compiles go on … after the game started after the first frame, and the first frame a few seconds after the hand-off (by
  hand: the parent's GPU slot).
• Windows and Linux, any GPU: build this PR (head d429f0f0, it carries #650, #651, #652 and #664) and main 6c9edffe
  the same way and start each to the title, expecting no behind the game, no giant compile starts until … line (the hold, the
  QoS class and the retry alone are compiled there and not reached), and every other line to match main's (by hand: test
  request T-XXXX).

Risks

What could break: on MoltenVK the giants behind the game wait for the first frame (at most 120 s), so they finish later; a
dispatch that needs one meanwhile compiles it itself, as before. The worker threads change QoS class (macOS only), which Metal
and the scheduler honour; the game's threads keep theirs. A giant that fails waits for its turn alone. Other drivers: the
header's code and the compile_retry check in create_watched, not reached there.

Turning it off: RX_VK_GIANT_HOLD_PRESENTS=0 (no hold), RX_VK_COMPILE_QOS=default (no class change),
RX_VK_COMPILER_SERVICE=0 (all of #652's path), or revert the PR.

Compatibility: Nothing changes for players on Windows and Linux: no shader stamp, cache format or MKWVK_API_VERSION
change.

Reviewer notes

• Review c291d0c6..d429f0f0 (3 commits; in git's notation 20367871..d429f0f0): the hold and the QoS class, their docs rows,
  and the retry alone.
• Depends on #664 (Giants, the bound this hold sits in), and through it on #652, #650 and #651. The branch is
  #664's head 20367871 plus this PR's commits.
• The topic's three commits were cherry-picked with -x from macos/title-stall (4f319a0d 36e04c5e b6069bba), made on the
  integration branch. Conflicts in the pick:
  • gpu/vk/vk_draw.cpp: #652's compiles_watched and this PR's compile_qos_apply added at the same place, both kept;
    behind_worker's compute arm: #652's adaptation to #252 (quick, precompile_compute_quick) and this PR's
    compile_retry/compute_alone, combined (the quick flag is set before the compile, the retry alone after a failure).
  • tests/test_precompile_handoff.py: #652's cached_* checks (main's create_cached line) kept, with this PR's
    compile_qos_apply checks.
  • docs/development.md: the rows take main's cache/longshot_pipelines.bin.slow (#321) with this PR's text; the integration
    branch's SPIR-V profile rows (a later macOS PR) are not here.
• No semantic commit: the pick's resolutions follow main's code, and the tests pass unchanged.
• Sibling macOS PRs: #666 builds on this branch and joins this PR's retry alone and its own into one place.
  git merge-tree of this head: no conflict with #423, #427, #431, #438, #476, #479, #480, #490, #491, #492; gpu/vk/vk_main.cpp
  with #428, #498 and #653, and vk_main.cpp/vk_progcache.cpp/vk_shader.h/vk_vendor.h with #646: the same conflicts as
  #652's own head, none from this PR's lines (reports/PubWave-files/PubLate1/merge-check-title-stall.txt).
• Conflicts with main: none.

Issues

See #420

Checklist

Everyone

• One topic.
• The title is a Conventional Commit (type(scope): description) of the status line's type.
• Why gives the reason plainly and links the issues that fit (the tracker searched).
• Measurements has a verdict, or one line saying why there is nothing to measure.
• Testing names what was tested, what wasn't, and what must still be tested, where and how. (Test requests not open yet.)
• Rebased on current main (main e090cc48).
• python -I -B tests/run_all.py passes (any failure that also fails on main is named). (On the wave's merge of the macOS PRs this one is built with, bfe5c752 (metal-cache2 + giant-mem-gate, which carry this PR): 544 passed, 32 failed, 17 skipped against main 6c9edffe's 531/32/17 on this Mac; the 32 failures are main's own, nothing that passes on main fails, 13 new tests pass; reports/PubWave-files/waveC1/.)
• No game files, dumps, build output or generated files.
• third_party/ untouched (a new folder with a PROVENANCE.md instead).
• The license is OK: GPL-3.0-or-later, nothing incompatible and nothing decompiled.

When it applies

• AI assistance recorded with Assisted-by: / Co-Authored-By: trailers.
• Switches documented (docs/development.md; the README for a menu row) and shipped at their recommended value.
• A game-free test added for the fix, failing on main and passing here.
• A check under tests/ that reads changed source updated in this PR, not weakened.
• Docs updated.

**Type:** fix · **Risk:** medium · **Tested on:** macOS 26.7.1, Apple M4 Max (MoltenVK 1.4.2), arm64 and x86_64 under Rosetta · **Needs:** macOS, Apple silicon (a start on the rebased stack); Windows and Linux, any GPU (build and start) ## Why On a Mac the game's first frame could wait minutes after the precompile had let it start. Metal's compiler service has a fixed number of connections (16 on an M4 Max), and the precompile's workers kept giant compute compiles running on all of them behind the game. The driver compiles a small blit program inside the game thread's first submit, and that request had to wait for a giant on its connection to end: in start 17 the game thread sat in `_dispatch_sync_f_slow` behind 16 giant compiles, and the first frame came only after the compiler service crashed under them, about 3 minutes after the hand-off. A giant whose compile failed that way was also compiled again at once among the other giants, where it failed again. This PR keeps the precompile's giants from starting behind the game until the game has shown its first frame, builds the giants and everything behind the game at a lower QoS class than the game's threads, and tries a failed giant again alone. It is part of the macOS port. See #420. ## How to reproduce **Seen on:** macOS 26.7.1, Apple M4 Max, MoltenVK 1.4.2 (main does not run on macOS yet: seen on the macOS port's integration build 4e472987, which carries the open macOS PRs) **Settings and switches:** defaults (start mode), the program cache carried from earlier starts **Steps:** start the game and wait for the title after the precompile's hand-off. **Expected:** the first frame a few seconds after the hand-off. **Actual:** start 17: the first frame came after the burst in which every giant still in flight failed (`XPC_ERROR_CONNECTION_INTERRUPTED … after multiple retries`), about 188-198 s after the hand-off; a sample at 08:25 had the game thread in `tryBoost` → `_dispatch_sync_f_slow` and 16 compiler connection threads each in a synchronous send (`reports/2026-11-14-mac-startup-17.md`; analysis in `reports/2026-11-14-title-stall.md` §1-§2). ## What changed Under `compiler_service` (MoltenVK only, #652), behind the game no compile of more than `RX_VK_GIANT_WORDS` starts until the game has shown `RX_VK_GIANT_HOLD_PRESENTS` (1) frames since the hand-off, or for `RX_VK_GIANT_HOLD_S` (120) s at most; the giants in flight at the hand-off finish, the held ones are deferred and built after it, never dropped. The precompile's workers build every giant, and everything behind the game, at QoS class utility (`RX_VK_COMPILE_QOS`); the rest, which the title waits for, keep the thread's own class. A giant compile that fails is not tried again at once among the other giants: its place is given back and it is compiled once more alone, with a new pipeline cache, once no other giant is in flight and none starts meanwhile. Every other driver is unchanged. - `gpu/vk/precompile_handoff.h` (no Vulkan): `giant_hold_presents`/`giant_hold_s`, `Giants::hold`/`release`/`held` (the hold in the gate), `compile_qos` and `qos_for` (which class a run is built at), `ThreadQos` (a worker's class, changed only when it must), `Retry` (Now, Later, Fresh) and `Giants::solo_ask`/`solo`/`solo_end`/`solo_cancel` (one giant alone, in turn). - `gpu/vk/vk_draw.cpp` `precompile_run`: the hold set at the hand-off and released by the presents counter or the time, one line when the giants go on; `behind_worker` takes the class for each run (`compile_qos_apply`: `pthread_set_qos_class_self_np` on macOS, nothing elsewhere); its compute arm marks a giant's compile `Retry::Later` and, when it failed, calls `compute_alone`; `create_watched`'s second try honours `compile_retry`. - `docs/development.md`: rows for `RX_VK_GIANT_HOLD_PRESENTS`/`RX_VK_GIANT_HOLD_S` and `RX_VK_COMPILE_QOS`; the `RX_VK_COMPILER_SERVICE` row names the retry alone. - tests: `tests/precompile_handoff_test.cpp` (the hold behind the game, the QoS choice, one giant alone at a time) and `tests/test_precompile_handoff.py` (the wiring; on macOS `vk_draw.cpp`'s own `compile_qos_apply` on a real thread, which shows that MoltenVK's way of asking for a compile, a block dispatched to the default global queue, runs at the worker's class). ## Measurements **Verdict:** works as designed in the game, but its own gain is not measured: on the integration builds that carry it the hold held the giants until the first frame (start 21: 143 deferred, released 27.0 s after the game started, 1,183 frames shown; start 24: 212 deferred, released after 46.2 s) and the first frame came 4.5-5.0 s after the hand-off (starts 21-24). Starts 18 and 19, with #664's bound but without this PR, also had their first frame 4.6 and 4.5 s after the hand-off, and the game-free probe TS-02 did not reproduce the wait (its blit program came from Metal's cache in 0.77 ms under 16 compiles). So this PR removes the wait's cause (no giant starts while the game has shown nothing) without a measured before/after of its own. No giant failed in starts 21-24, so the retry alone did not run. Baseline: main does not run on macOS yet, so the columns are the macOS port's integration builds, arm64, MoltenVK 1.4.2, start mode. Before: 4e472987 (start 17: no bound, no hold). After: 09f9a171 (start 21, Integration 28, which carries this topic and #666). One run each. Hardware: macOS 26.7.1, Apple M4 Max (40-core GPU), MoltenVK 1.4.2, 16-core CPU, 64 GB Scene: a start to the title, windowless, defaults Method: the game log's hand-off line, the hold lines and the first `vk: present texture … rendered` line, one run each; the probe TS-02 (`reports/TitleStall-files/ts02/run-01-arm64/`, `summary.json` `53fddf57…`) How to reproduce: a start of a macOS build from a seeded cache; `RX_VK_GIANT_HOLD_PRESENTS=0` turns the hold off | | Before: integration @ 4e472987 (start 17) | After: integration @ 09f9a171 (start 21) | |---|---|---| | giants in flight at the hand-off | 16 (no bound) | 4 at most before, 3 behind the game | | giants started behind the game before the first frame | not held | none (143 deferred until the first frame) | | hand-off → first frame | about 188-198 s [inferred from the log, §1 of the report] | 5.0 s | | compiler-service crashes | 13 | 6 | ``` #21: vk: precompile: behind the game, no giant compile starts until the game has shown 1 frames (0: none waits), 120 s at most (RX_VK_GIANT_HOLD_PRESENTS, RX_VK_GIANT_HOLD_S); the workers build the giants, and everything behind the game, at QoS class utility (RX_VK_COMPILE_QOS) #21: vk: precompile: behind the game: giant compiles go on, 27.0 s after the game started, which has shown 1183 frames since (they waited for 1; 143 deferred until then; RX_VK_GIANT_HOLD_PRESENTS, RX_VK_GIANT_HOLD_S) #24: vk: precompile: behind the game: giant compiles go on, 46.2 s after the game started, which has shown 1837 frames since (they waited for 1; 212 deferred until then; …) ``` Run reports: `reports/2026-11-14-mac-startup-17.md`, `-18.md`, `-19.md`, `-21.md`, `-22.md`, `-24.md`; the analysis and TS-01/TS-02: `reports/2026-11-14-title-stall.md`. ### Flags and settings Three new switches, read only with `RX_VK_COMPILER_SERVICE` (MoltenVK); nothing changes elsewhere. | Flag | What it is | Before this PR | After this PR | Effect | Helps / doesn't help / untested | Recommendation | |---|---|---|---|---|---|---| | `RX_VK_GIANT_HOLD_PRESENTS` | frames the game must show after the hand-off before a giant starts behind it; `0`: no hold | (no switch) | 1 | the game's first submit finds the compiler's connections free of new giants | helps: MoltenVK (starts 21-24, the hold seen); untested: other values | as it ships | | `RX_VK_GIANT_HOLD_S` | the hold's longest time, so a start that shows no frame still builds them | (no switch) | 120 | bounds the hold | untested beyond the default | as it ships | | `RX_VK_COMPILE_QOS` | `utility`, `background` or `default`: the class giants and work behind the game are built at | (no switch) | utility | Metal serves the game's own compile requests first | helps: shown on a real thread (the test); untested in the game against `default` | as it ships | ## Testing **Tested:** on macOS 26.7.1, Apple M4 Max, at this head (main 6c9edffe plus #650, #651, #652, #664 and this PR): - `tests/test_precompile_handoff.py --arch arm64` and `--arch x86_64` (the fixtures run under Rosetta): pass on both (the hold, the QoS choice and fixture, the retry alone, and every earlier check). On this branch's base (#664 `20367871`) with the test files copied in (sha256 in `ts-test-files.sha256`): fails on both, the fixture does not build and the source checks name what is missing (`precompile_run lacks: … giant_hold_presents …`, `… compile_qos …`) (`reports/PubWave-files/PubLate1/tsls-proof-01/ts-*`). - `tests/test_warm_handoff.py --arch arm64` still passes (`tsls-proof-01/ts-warm-arm64`). - Every check that reads a renderer file changed by #650, #651, #652, #664 or this PR, and the new ones (301 names, 299 checks on this branch), through `tools/ls-suite.py`: 279 pass, 20 fail. 19 are the same 19 as at #652's head (16 also fail on main 6c9edffe on macOS; 3 are skipped on macOS in a full run and fail only because named); the 20th is `test_gpu_hang_watch` ("exit 3, 3.5 s" against its 3.4 s bound, at load 44-50), the suite's known load-sensitive timing test, which reads no file this PR changes (`title-stall-related-01/`, `title-stall-related-01-compare.txt`). - `gpu/vk/vk_draw.cpp` compiled whole for arm64 and x86_64 with main's renderer flags (with #476's and #492's macOS compile pieces in a scratch tree): both objects made, exit 0 (`reports/PubWave-files/PubLate1/compile/title-stall/`). - Off Apple (`unifdef -U__APPLE__`, base against head): `precompile_handoff.h` and `vk_draw.cpp` differ: the header's new pieces; in `vk_draw.cpp` `compile_qos_apply`'s off-Apple body (`(void)q;`), the thread-local `compile_retry` and `compile_failed_later`, and `create_watched`'s second try and line reading `compile_retry`, which is `Now` there (only `behind_worker`, under `compiler_service`, sets another), so `create_watched` (reached off Apple only with `RX_VK_SLOW_COMPILE_S` set) tries again and logs as before (`reports/PubWave-files/PubLate1/offapple-title-stall.txt`). - In the game (integration builds carrying these commits, before the rebase): starts 21-24, above. **Not tested:** the game at this head (main does not run on macOS without the other macOS PRs); the retry alone in the game (no giant failed in starts 21-24); the QoS class's effect in the game against `RX_VK_COMPILE_QOS=default`; Windows and Linux (the new code runs only under `compiler_service`, off there; it is compiled there): not built on Windows or Linux; its test request covers it. **Must be tested:** - macOS, Apple silicon, on the rebased macOS stack: a start from a seeded cache, expecting the hold line at the hand-off, `giant compiles go on … after the game started` after the first frame, and the first frame a few seconds after the hand-off (by hand: the parent's GPU slot). - Windows and Linux, any GPU: build this PR (head `d429f0f0`, it carries #650, #651, #652 and #664) and main 6c9edffe the same way and start each to the title, expecting no `behind the game, no giant compile starts until …` line (the hold, the QoS class and the retry alone are compiled there and not reached), and every other line to match main's (by hand: test request T-XXXX). ## Risks **What could break:** on MoltenVK the giants behind the game wait for the first frame (at most 120 s), so they finish later; a dispatch that needs one meanwhile compiles it itself, as before. The worker threads change QoS class (macOS only), which Metal and the scheduler honour; the game's threads keep theirs. A giant that fails waits for its turn alone. Other drivers: the header's code and the `compile_retry` check in `create_watched`, not reached there. **Turning it off:** `RX_VK_GIANT_HOLD_PRESENTS=0` (no hold), `RX_VK_COMPILE_QOS=default` (no class change), `RX_VK_COMPILER_SERVICE=0` (all of #652's path), or revert the PR. **Compatibility:** Nothing changes for players on Windows and Linux: no shader stamp, cache format or `MKWVK_API_VERSION` change. ## Reviewer notes - Review `c291d0c6..d429f0f0` (3 commits; in git's notation `20367871..d429f0f0`): the hold and the QoS class, their docs rows, and the retry alone. - Depends on #664 (`Giants`, the bound this hold sits in), and through it on #652, #650 and #651. The branch is #664's head `20367871` plus this PR's commits. - The topic's three commits were cherry-picked with `-x` from `macos/title-stall` (`4f319a0d 36e04c5e b6069bba`), made on the integration branch. Conflicts in the pick: - `gpu/vk/vk_draw.cpp`: #652's `compiles_watched` and this PR's `compile_qos_apply` added at the same place, both kept; `behind_worker`'s compute arm: #652's adaptation to #252 (`quick`, `precompile_compute_quick`) and this PR's `compile_retry`/`compute_alone`, combined (the quick flag is set before the compile, the retry alone after a failure). - `tests/test_precompile_handoff.py`: #652's `cached_*` checks (main's `create_cached` line) kept, with this PR's `compile_qos_apply` checks. - `docs/development.md`: the rows take main's `cache/longshot_pipelines.bin.slow` (#321) with this PR's text; the integration branch's SPIR-V profile rows (a later macOS PR) are not here. - No semantic commit: the pick's resolutions follow main's code, and the tests pass unchanged. - Sibling macOS PRs: #666 builds on this branch and joins this PR's retry alone and its own into one place. `git merge-tree` of this head: no conflict with #423, #427, #431, #438, #476, #479, #480, #490, #491, #492; `gpu/vk/vk_main.cpp` with #428, #498 and #653, and `vk_main.cpp`/`vk_progcache.cpp`/`vk_shader.h`/`vk_vendor.h` with #646: the same conflicts as #652's own head, none from this PR's lines (`reports/PubWave-files/PubLate1/merge-check-title-stall.txt`). - Conflicts with main: none. ## Issues See #420 ## Checklist ### Everyone - [x] One topic. - [x] The title is a Conventional Commit (`type(scope): description`) of the status line's type. - [x] Why gives the reason plainly and links the issues that fit (the tracker searched). - [x] Measurements has a verdict, or one line saying why there is nothing to measure. - [ ] Testing names what was tested, what wasn't, and what must still be tested, where and how. (Test requests not open yet.) - [x] Rebased on current `main` (main e090cc48). - [x] `python -I -B tests/run_all.py` passes (any failure that also fails on `main` is named). (On the wave's merge of the macOS PRs this one is built with, `bfe5c752` (metal-cache2 + giant-mem-gate, which carry this PR): 544 passed, 32 failed, 17 skipped against main 6c9edffe's 531/32/17 on this Mac; the 32 failures are main's own, nothing that passes on main fails, 13 new tests pass; `reports/PubWave-files/waveC1/`.) - [x] No game files, dumps, build output or generated files. - [x] `third_party/` untouched (a new folder with a `PROVENANCE.md` instead). - [x] The license is OK: GPL-3.0-or-later, nothing incompatible and nothing decompiled. ### When it applies - [x] AI assistance recorded with `Assisted-by:` / `Co-Authored-By:` trailers. - [x] Switches documented (docs/development.md; the README for a menu row) and shipped at their recommended value. - [x] A game-free test added for the fix, failing on `main` and passing here. - [x] A check under `tests/` that reads changed source updated in this PR, not weakened. - [x] Docs updated.

mooki added 22 commits 2026-11-15 02:55:06 +00:00

fix(macos): the shader preparation runs on every usable CPU on macOS ... 1843f6f809

prepare_run's first part (every shader translated, and each compute
variant compiled for the pipeline cache) ran on half the CPUs
everywhere: prepare_cpus gives half_cpus unless the Windows process heap
is the segment heap. Half exists for the NT heap's lock that an
in-process driver compiler queued on, and for whole-PC freezes when
those compilers ran on every CPU at High priority. Neither holds on
macOS: MoltenVK converts SPIR-V to MSL in a few ms and hands every
compile to Metal's compiler service (MTLCompilerService, a launchd
service at nice 0), so the workers mostly wait on it. The Mac's first
start logged "8 workers for the shader programs (16 CPUs usable; half
the CPUs)".

prepare_workers::count takes an `every` argument (default false): each
usable CPU gets a worker, at least half_cpus and 1, at most kMaxWorkers.
kEveryCpu is true where __APPLE__ is defined, and prepare_cpus passes
it; the preparation's log line says "every one: macOS". In a synthetic
MoltenVK 1.4.2 benchmark on an M4 Max (16 CPUs, macOS 26.7.1) 16 threads
compiled 56-61 % more compute and 35-39 % more graphics pipelines a
second than 8, but only with a pipeline cache per thread; with the one
shared cache LS uses today the rate is flat from 4 to 16 threads. The
next commit gives each worker its own cache.

tests/test_prepare_every_cpu.py compiles the real prepare_workers.h and
prepare_cpus() cut from vk_progcache.cpp: on this compiler's target
prepare_cpus() gives 16 of 16 usable CPUs on macOS (8 elsewhere); count
with and without `every`; prepare_cpus with kEveryCpu forced either way.
On the base it fails: prepare_cpus() gives 8 of 16 on macOS.

Windows and Linux: unchanged (kEveryCpu false; the existing
test_prepare_workers and test_prepare_cpus cases are untouched).

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 3573e736e15078554543e4740c5e2d53c719fa89)

fix(macos): a pipeline cache per preparation worker on MoltenVK ... 55749103ac

MoltenVK 1.4.2 holds one mutex per VkPipelineCache across the SPIR-V to
MSL conversion and Metal's library compile (MVKPipeline.mm
getShaderLibrary, _shaderCacheLock). Every worker of the start's
preparation compiled with the one start cache, pcache, so they compiled
one pipeline at a time: the Mac's first start (mac-arm64-a5f2d6f9-01,
M4 Max) logged strict pairs of Metal compiles every ~195 ms, 5.05
compute variants a second, an estimated 33 minutes for the compute
programs alone. A synthetic benchmark on that Mac (PrepSpeed, MoltenVK
1.4.2, macOS 26.7.1): one shared cache stays at 10.5 compute and 9.6
graphics pipelines a second from 4 to 16 threads; a cache per thread,
merged after, gives 31.5 / 29.7 at 8 threads and 49-51 / 40-41 at 16.

gpu/vk/worker_caches.h: a Set of empty caches, one per worker of a
phase, that a worker enters with Scope; create() asks the shared cache
first under VK_PIPELINE_CREATE_FAIL_ON_PIPELINE_COMPILE_REQUIRED_BIT
and compiles what it lacks with the worker's own; merge_into() merges
them into the start cache with one vkMergePipelineCaches in slot order
(MoltenVK retains each Metal library, no compile). The caches are not
externally synchronized, so a shared slot stays correct.

vk_draw.cpp:
- create_cached: before play, a worker in a phase with a set goes
  through worker_caches::create (pcache asked first, so a saved file's
  or an earlier phase's pipelines are found as before); every use of
  pcache holds pcache_mu shared, and worker_caches_merge holds it alone
  (vkMergePipelineCaches's dstCache is externally synchronized:
  vk.xml externsync without INTERNALLY_SYNCHRONIZED_MERGE). A save's
  reads of pcache's data hold it shared too.
- prepare_run (the compute warm), precompile_run, precompile_warm (both
  passes) and precompile_at_create make a set under worker_caches_on,
  enter it in their workers and merge it right after the join; the
  precompile's stragglers left running are merged as far as they got.
- precompile_run, with the caches on, sorts the notes by program
  variant and hands a variant's notes to one worker in runs of up to
  32 (worker_caches::runs/claim), so its shader libraries are compiled
  once, not by every worker that met one of its notes at the same time.
- In play, with the caches on, a compile goes into a new cache of its
  own merged into the generation's at once under the generation's lock
  (made_alone), which the asks of the generation hold shared: the asks
  keep their order and find what any thread compiled.

vk_vendor.h: worker_caches, on for VK_DRIVER_ID_MOLTENVK only, and only
with pipelineCreationCacheControl; RX_VK_WORKER_CACHES forces it either
way. Elsewhere nothing measured says a driver's cache is locked across
its compiles, and the caches would only add merges. The pipelines built,
the persisted cache's format and its stamp are the same either way.

tests/test_worker_caches.py runs vk_draw.cpp's own create_cached,
play_cache_make, worker_caches_on and worker_caches_merge and the real
header against a made-up driver whose caches lock across a compile:
four workers compile at once (without a set they cannot); pcache asked
first, nothing compiled with it; ask-only callers never compiled; caches
not externally synchronized; one merge in slot order whatever order the
slots were taken in, with no ask of pcache beside it; play's compiles
merged into the generation at once; runs and claims. The four-workers
part runs against the base's create_cached and fails there (1 of 4
compiles met the others). tests/test_pipeline_play_cache.py gets an
"alone" case, and both play-cache and cache-save harnesses the new
stand-ins (pcache_mu, worker_caches_on).

Windows and Linux: the same code paths as before (no set, one shared
cache), plus an uncontended shared lock around pcache's uses.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 2174e33f14ccce8c1635565e734773a33bc32455)

fix(macos): the worker caches make no Vulkan call from a header ... b5f4f1febd

tests/test_recorder_sync.py holds every header to no recorder boundary
call: vk_work.h, included last by each renderer .cpp, turns
vkDestroyPipelineCache into a drain of RX_VK_RECORDER's packets and then
the call, and a header's calls would be wrapped or not depending on what
included it. worker_caches.h called vkCreatePipelineCache,
vkDestroyPipelineCache and vkMergePipelineCaches itself, from vk_draw.cpp
before vk_work.h.

worker_caches::Set and made_alone now take a Calls struct with the
three operations; vk_draw.cpp defines worker_cache_calls after
vk_work.h, so a set's cache destruction goes through the recorder's
boundary like every other vkDestroy* in the file. Behaviour is
otherwise the same: the same caches, made, merged and destroyed in the
same order.

tests/test_worker_caches.py and tests/pipeline_play_cache_test.cpp take
worker_cache_calls from the source and the model respectively.
test_recorder_sync now fails only as on the base (vk_vma.cpp's
vmaDestroyAllocator), and the four tests that touch the caches pass.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit aa8ecba546465f1ce65ac872ecf21d232b65cef0)

fix(macos): MoltenVK starts with an empty pipeline cache and writes none ... f59051783e

MoltenVK 1.4.2 keeps MSL, not GPU code, in a VkPipelineCache, and
vkCreatePipelineCache with saved data compiles every stored library one
after another on the calling thread (MVKPipeline.mm readData).
pcache_init hands it all of mkw_vk_pipelines.bin, and play_files_merge
every play file, at every start. The PrepFast GPU check on the M4 Max,
with Metal's per-user cache blocked as in the runner, ran three later
starts of the same 64 pipelines (80 libraries):
- reading the one file: 5.7 s of serial compiles, 6.6 s in all;
- 16 shards read in parallel: 1.4 s;
- nothing read, pipelines compiled from SPIR-V with the worker caches:
  1.4 s.
At the game's scale the read is tens of minutes per start.

vk_vendor.h gets pcache_no_load, on for VK_DRIVER_ID_MOLTENVK only and
logged in the vendor fixes' line with worker_caches. It is the device's
default for RX_VK_PCACHE_LOAD: pcache_load_off reads the switch first
(any value, as before) and falls back to the fix, so
RX_VK_PCACHE_LOAD=1 reads the files on MoltenVK as everywhere else. With
the fix on and the switch unset or off, pcache_files_unused holds:
- pcache_init reads neither the main file nor the play files and says
  so in the log; the cache lives in memory for the run;
- nothing is saved (pcache_no_save, as RX_VK_PCACHE_LOAD=0 already
  did), and play_cache_save writes no play file and keeps the
  generation in memory: unread play files would pile up, since they
  are compacted only where they are read;
- the stamp is left alone (pcache_drop_stale returns as for any
  start that does not read the files);
- precompile_run drops RX_VK_LOAD=create's longshot_pipelines.bin.built
  marker at each start, as it does when the files were dropped: no
  cache a later start reads holds the notes, so the warm builds them
  into the in-memory cache again before loads at create ask for them.

Saving does not continue on MoltenVK because nothing reads the file or
its stamp there:
- the prepared record (prepared_for) has its own file and stamp;
- --prepare-shaders' saved cache is useful only to a start that reads
  it;
- pcache_saved_now serves graphics pipeline libraries, which MoltenVK
  does not have;
- a start with RX_VK_PCACHE_LOAD=1 makes, saves and stamps its own.
Every other driver is unchanged, RX_VK_PCACHE_LOAD=0 there included
(main file unread and unsaved, play files still merged and written).

tests/test_vendor_fixes.py checks the two cache fixes on its 16 devices
and on MoltenVK: on for MoltenVK alone, RX_VK_WORKER_CACHES forcing
the first, vendor_fixes_env leaving pcache_no_load to the files'
switch. It also checks the log line and pcache_load_off's order.
tests/test_pcache_stamp.py runs pcache_load_off, pcache_files_unused,
pcache_drop_stale and pcache_init, cut from the source, in eight starts:
other drivers unset, 0, empty and 1 as before, and MoltenVK unset, 0,
off and 1. test_pipeline_play_cache gets an "unused" case. All three
fail on aa8ecba5. tests/test_warm_bounded.py's source check of the
marker's removal takes the new condition.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 61bfbf1ae7c0966a9436ab0c556a9ee547bb3b5f)

fix(vk, macos): the renderer's threads start with a 16 MiB stack, not macOS's 512 KiB ... f0a62f7ba0

macOS starts a std::thread with 512 KiB of stack, where Linux starts one
with 8 MiB and Windows with longshot.exe's 8 MiB. On macOS MoltenVK
converts each shader with SPIRV-Cross on the thread that creates the
pipeline, recursing once per block of a program's control flow, and a
prepare_run worker overran its 512 KiB there (CFG::walk_from under
vkCreateComputePipelines from seed_compute, start #6, 2026-11-14).

gpu/vk/thread_stack.h: thread_stack::thread is std::thread itself off
macOS; on macOS a std::thread-like thread (construction with decayed
arguments, joinable, join, detach, native_handle, moves) started by
pthread_create with thread_stack::kBytes (16 MiB) of stack. Every
thread the renderer starts goes through it: the preparation's pools
(prepare_run, state_list_prepare, warm_libraries, precompile_at_create,
precompile_run, predict_run, warm_bounded::run), the job workers and
the serial builder, the replay, parallel-replay, presenter and
frame-generation threads, the program cache's loaders and the rest.
mkwvk_init logs the size once per start on macOS.

tests/test_thread_stack.py: no file under gpu/vk starts a thread any
other way; each kind of thread runs a recursion 2 MiB deep through the
helper, and on macOS each overflows as a std::thread (caught, no crash
report). Seven source checks follow the new spelling.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 48b49054b1c64851b3e8c974e64dc0b757b2ced3)

test(macos): one overflow message from thread_stack_test, however many threads overflow at once ... ea4081d942

The first thread whose stack overflows says so and ends the process;
the others wait in their handlers, so the message is not interleaved.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 62d0991e0cfb5402202f8f14e9eb799d5c20d262)

test: the checks that compile renderer code with its threads see thread_stack.h ... 7707c63433

Eight checks cut renderer functions that start threads (or copy
vk_jobs.cpp and vk_recorder.h) into fixtures of their own; they now
build with gpu/vk/thread_stack.h beside them: test_capture_copy_helpers,
test_gpu_hang_watch, test_jobs_failure, test_jobs_wait_runs_queued,
test_pipeline_cache_save, test_prepare_stall, test_present_source_crop
and test_recorder_sync.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit fd46ff431f9f62b1125582a4a3434a8cc92c551e)

fix(macos): the worker caches follow main's fetch lock (#190) and Intel's gate (#252) ... 078c9a7a54

Main's #190 (f41a5c59) put a fetch lock (PcacheFetch, PcacheUse) on the pipeline cache's save and compile path, the
very path where the worker caches add the lock their merges need, and #252 (57f4eaec) put Intel's compiler gate
(IntelDriverGate) around the compiles. The worker caches now sit on top of both:

- pcache_mu, the merge lock, is taken only where the worker caches are on (pcache_use_held: MoltenVK by default).
  Elsewhere create_cached, the save's fetch and pcache_saved_now take exactly #190's locks, as on main: no new lock
  on any other driver. A play generation's lock is likewise taken only where play's compiles are merged into it
  (g->alone).
- The worker caches are never on with the fetch lock (worker_caches_on: not with pcache_fetch_lock_on, Intel's
  Windows driver or RX_VK_PCACHE_FETCH_LOCK=1): a merge reads its caches' data as a fetch does, which that lock keeps
  apart from the builds there, and the gate lets one compile at a time into Intel's compiler there anyway.
- The order of the locks: Intel's gate, then pcache_mu, then the fetch lock. The save's fetch and pcache_saved_now
  take pcache_mu before PcacheFetch; a merge takes pcache_mu alone.
- prepare_run's compute warm keeps #252's gate around its compile and, with the caches, goes through create_cached
  under it (cached_compute would take the gate a second time).
- tests: test_worker_caches checks the gating (with the caches off a pipeline is made while pcache_mu or the
  generation's lock is held alone elsewhere; with them on it waits for pcache_mu), worker_caches_on against the
  fetch lock, the warm's gate and pcache_mu ahead of PcacheFetch in the save. test_pipeline_play_cache's route case
  checks that no lock of theirs is taken off MoltenVK; pipeline_play_cache_test.cpp and pipeline_cache_save_test.cpp
  get pcache_use_held stand-ins. test_pcache_stamp's load fixture follows #321's cache_path and #190's PcacheFetch in
  pcache_init, and play_cache_save's new parameters.
- docs: #321's cache/longshot_vk_pipelines.bin in the RX_VK_WORKER_CACHES row and in vk_vendor.h, and a row for
  RX_VK_PCACHE_LOAD, whose default this PR changes on MoltenVK.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>

merge(macos): the renderer threads' 16 MiB stacks (mac/thread-stack 7707c634) under the precompile hand-off ... f9f166f7cb

The precompile hand-off starts its workers and its compile watcher through thread_stack::thread. One conflict file,
gpu/vk/vk_draw.cpp (4 blocks: the lines P31 had to resolve against main, the other way round): the include block keeps prepare_workers.h,
worker_caches.h and thread_stack.h; prepare_run's, precompile_at_create's and precompile_run's thread lines take
thread_stack::thread and keep the worker caches' merges beside them.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>

fix(vk): MoltenVK: the precompile goes on behind the game; slow compiles named; a failed compile tried once more ... 89606310bb

On the Mac's start 12 every precompile worker was held by a Metal compile of minutes while 37,600 of
42,234 items were still to hand out, so RX_VK_PRECOMPILE_STALL_S could not apply (it waits until every
item is handed out) and the title never came. With the new vendor fix compiler_service (MoltenVK only,
RX_VK_COMPILER_SERVICE):
- the precompile hands the rest to the game once nothing has finished for the stall time, or once all
  that is left is compiles running past RX_VK_SLOW_COMPILE_S; a quarter of the workers build the rest
  behind the game, every item still built, each straggler named when it ends;
- its order: noted pipelines first, then fallbacks and computes by SPIR-V words, what an earlier run
  found slow (longshot_pipelines.bin.slow) last;
- a compile over the slow time (10 s) is named with key, variant, kind, stage and SPIR-V words while it
  runs and when it ends, and written to the slow list;
- a pipeline whose compile failed is compiled once more with a new pipeline cache (MoltenVK keeps a
  failed library in the cache it was compiled with), and said made or not made.
Every other driver: the classic worker, wait and log line as they were.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 77d4971cbdb6356d9064a44cdee923f4bde354f9)

test(vk): test_precompile_handoff: a tree without the change says each missing piece ... 306ffd28ca

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit f9a179c08d3f9e102729ec8fe5fe923336f581b8)

docs: RX_VK_PRECOMPILE_STALL_S, RX_VK_COMPILER_SERVICE and RX_VK_SLOW_COMPILE_S ... 44f210178c

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 194a230dd959706797203501edad3b5a2331118a)

fix(vk): name a graphics compile at its precompile callers, not inside build_graphics ... ab2bf44680

test_fallback_pipeline_state compiles build_graphics cut from the source; the noted pipelines of behind_worker and precompile_warm name what they build instead.

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 528784dc5c0c293da1b692f6fd71da070a940d8b)

fix(vk): the precompile hand-off on main's Intel gate and quick builds (#252), fetch lock (#190) and game folder (#321) ... 7ef7cff977

The hand-off was written on the macOS integration branch, before main's #190 (f41a5c59), #252 (57f4eaec) and #321
(76699aad), and before the worker caches followed them (this branch's base). What it needs on main's code:

- cached_graphics and cached_compute keep #252's gate and main's `return create_cached(guarded_*_held, ci, pl);`, and go
  through create_watched only where compiles are watched (compiles_watched: compiler_service, MoltenVK's, or
  RX_VK_SLOW_COMPILE_S set). Every other driver makes its pipelines exactly as on main, and main's own source checks
  (test_intel_compiler_gate, test_pcache_fetch_lock) read the lines they read there.
- prepare_run's compute warm: with the worker caches and watched compiles through create_watched, under the gate it holds;
  otherwise P22's create_cached or main's guarded_compute_held, as they are.
- behind_worker, the precompile's worker under compiler_service, builds a compute pipeline as the classic worker now
  does (#252): on Intel's one-at-a-time builds (serial_builds_on) without the optimizer first, the optimized build owed
  to its first dispatch (precompile_compute_quick, optimize_owed). On MoltenVK, where compiler_service is on, that never
  applies unless RX_VK_COMPUTE_SERIAL=1; it keeps the two workers' builds the same.
- test_precompile_handoff's source checks follow main's spellings: the watched and plain lines in cached_* after the gate,
  compiles_watched, the warm, the dispatch's inline build named as main spells it (p, not the integration branch's plain),
  and behind_worker's quick build.
- docs: the slow list is cache/longshot_pipelines.bin.slow since #321 moved the notes into the game folder's cache/.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>

fix(vk): under compiler_service the preparation leaves the compute pipelines to the precompile ... abfc05c8ea

On the Mac's cold start 14, prepare_run's compute warm kept 13 of its 16 workers on compute compiles of
122k-209k SPIR-V words for 205-274 s each. The preparation reached 278 of 38,809 programs in 430 s, and the
precompile, whose hand-off lets the title start while such compiles go on behind it, never began.

With compiler_service (MoltenVK only) the warm compiles nothing. Each compute variant is still translated and
kept by seed_compute (program_cache_save), and the state list and the prepared record follow as before. The
precompile compiles the pipelines: every kept compute program on a first start (computes_plan), in its order
and with its hand-off; one it does not take is compiled at its first dispatch. Every other driver's warm is
unchanged.

tests/test_warm_handoff.py runs prepare_run's own decision and warm_compute against stand-ins on both arches,
and pins the source chain that keeps each variant for the precompile.

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 84c32d68c536468b61af24230ea8c283c5f091ef)

fix(vk): at most four giant compiles at once in the precompile under compiler_service ... bd313bffae

Start 14 had 13 compute compiles of 122k-209k SPIR-V words in flight at once while the other programs went
at 0.1-0.3 a second, and Metal's compiler service aborted twice (LLVM bad_alloc).

precompile_handoff.h Giants: at most RX_VK_GIANT_COMPILES (4) compiles of more than RX_VK_GIANT_WORDS
(100,000) SPIR-V words in flight at once among behind_worker's workers, before the game and behind it. A
giant claimed while the bound is reached is deferred, never dropped, and named once with a count; its
worker takes the next item, and the deferred ones are taken first once a giant ends. A worker with nothing
else waits for them and leaves only when none is deferred. behind_worker claims with claim_below, which
never passes the end, and a worker adds its one "ran out" to next as it leaves, so the wait's
next >= total + threads still means every worker has left. The classic worker (every other driver) is
unchanged.

The precompile_handoff fixture runs the gate with blocking giants: at most 2 of 6 in flight, the small
items going on meanwhile, each deferral named once with its count, every item built once, before the game
and behind it with the hand-off.

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit f1e028c8db05ef31383fa44c05fa156984c0f6c9)

docs: RX_VK_GIANT_COMPILES and RX_VK_GIANT_WORDS; the preparation's compute pipelines under compiler_service ... 1725c432f4

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 8aaa2f33d51b6b6f8db335cac69639137833537e)

fix(vk): giant compiles never hold every worker of a phase ... e10c0ad542

The bound on giant compiles in flight is now min(RX_VK_GIANT_COMPILES, workers in the phase - 1), and at
least 1. Before the hand-off the phase is the precompile's workers (16 on an M4 Max: 4); at the hand-off
precompile_run sets it to the share behind the game (4 workers: 3), so one worker there always stays on the
smaller items. Giants already in flight over the new bound finish; no more start until they are under it.
RX_VK_GIANT_COMPILES=0 is still no bound. The order line, the hand-off line and each deferral line give the
bound in use; docs/development.md says so.

The precompile_handoff fixture gains a hand-off by the stall time with three giants (4 workers: 3) and a
stuck small item holding every worker and most of the list still to hand out: behind the game, on a share
of 2, one giant at a time and the other worker on the small items, every item built once. Plus limit_for
and phase.

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit acd3a71a2717b1e1bfc83c1952932fdcf1afd9de)

test(vk): test_warm_handoff follows main's warm and dispatch (#252, #190) ... 20367871b5

The fixture cuts prepare_run's warm out of vk_draw.cpp. On main the warm builds
under Intel's compiler gate (#252 IntelDriverGate) through guarded_compute_held,
with the worker caches through create_cached (#190, PrepFast) or create_watched
where compiles are watched (PrecompileStall's compiles_watched). The fixture now
has stand-ins for those; without worker caches, as there, the warm still goes to
guarded_compute_held into pcache and is counted the same way.

The source check for a dispatch's build of an unmade compute pipeline reads
main's name for the dispatch's program, p (the topic's tree had a later
rename to plain).

Assisted-by: Claude Opus 5.5

Co-Authored-By: Claude Opus 5.5 <[email protected]>

fix(vk): behind the game no giant compile starts before the first frame; the precompile's giants and its work behind the game below the game's QoS class ... c291d0c67d

Run 17 (MoltenVK 1.4.2, M4 Max): the game thread's first vkQueueSubmit2 waited about four minutes in
MVKCmdBufferImageCopy::encode. The AGX driver compiled a blit program variant for the copy synchronously
(findOrCreateBlitProgramVariant -> MTLCompilerScheduler::buildRequest -> MTLXPCCompilerConnection::tryBoost ->
dispatch_sync), and its request waited on one of Metal's 16 compiler connections behind a giant compute compile
that ended only when the compiler service, crashing under 16 of them, gave up on it.

Under compiler_service (MoltenVK) only:
- Giants::hold: from the hand-off, no compile of more than RX_VK_GIANT_WORDS starts until the game has shown
  RX_VK_GIANT_HOLD_PRESENTS frames (1), or RX_VK_GIANT_HOLD_S (120 s) at most; the ones in flight finish, the
  deferred ones go first after it. Nothing is dropped.
- RX_VK_COMPILE_QOS (utility): behind the game every run, and every giant before it, is built at QoS class
  utility; the rest, which the title waits for, at the thread's own (DEFAULT, the game threads' class).
  MoltenVK dispatches each Metal compile from the calling thread to the default global queue, whose QoS is a
  fallback only, so the request carries the worker's class.

The classic worker and every other driver are unchanged; compile_qos_apply does nothing off macOS.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 4f319a0d9a658d4205d52fe25be645443764ed75)

docs: RX_VK_GIANT_HOLD_PRESENTS, RX_VK_GIANT_HOLD_S and RX_VK_COMPILE_QOS ... b0c650ef74

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit 36e04c5eb85f15398ec3a82afdef7205bd37e304)

fix(vk): a giant compile that failed is tried once more alone, not at once among the other giants ... d429f0f08d

Runs 17 and 18 (MoltenVK 1.4.2, M4 Max): Metal's compiler service aborted 13 and 7 times on an LLVM
allocation failure while it held giant compute compiles, and each abort takes every compile of that
instance with it (up to 8). A giant that came back VK_ERROR_INITIALIZATION_FAILED was compiled again
at once, with a new pipeline cache, among the giants still in flight.

Under compiler_service (MoltenVK) only, in the precompile's behind_worker: a giant's failed compile is
only said (create_watched, Retry::Later); its worker gives its place back (Giants::solo_ask) and waits
until no other giant is in flight and none is held, while no giant starts (Giants::solo), then
compiles it once more with a new pipeline cache (Retry::Fresh) and says so. Its compute_state stays
claimed meanwhile; a stop cancels its turn. Every other compile, and every other driver, as before.

Assisted-by: Claude Opus 5.5
Co-Authored-By: Claude Opus 5.5 <[email protected]>
(cherry picked from commit b6069bbab0719980b61f26c6b1df469f989f930a)

mooki referenced this pull request 2026-11-15 02:55:21 +00:00

WIP: fix(macos): leave MoltenVK's compute pipelines to the precompile and bound its giant compiles #664

mooki referenced this pull request 2026-11-15 02:55:23 +00:00

WIP: fix(macos): put a dispatch's compute pipeline ahead of MoltenVK's giant compiles and retry it alone, not fail it for good #666

mooki referenced this pull request 2026-11-15 02:55:25 +00:00

WIP: feat(macos): RX_VK_METAL_ARCHIVE_DIR keeps MoltenVK's pipelines in Metal binary archives #667

mooki referenced this pull request 2026-11-15 03:11:18 +00:00

WIP: fix(macos): start MoltenVK's giant compiles behind the game only while memory allows, and say a lost device as one #669

mooki force-pushed mac/title-stall from d429f0f08d to 40edc9da95 2026-11-15 07:25:42 +00:00 Compare

mooki referenced this pull request 2026-11-15 11:56:02 +00:00

WIP: fix(vk): heavy compiles run alone under Metal's compiler service; the first giant behind the game no longer waits for 16 GB #784

mooki referenced this pull request 2026-11-15 11:56:08 +00:00

WIP: fix(macos): KosmicKrisp's compiles go through the compiler service's precompile, as MoltenVK's do #785

mooki force-pushed mac/title-stall from 40edc9da95 to a7e966ec87 2026-11-15 13:54:54 +00:00 Compare

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malon referenced this pull request 2026-11-15 15:11:03 +00:00

Game: Keeps on crashing in death mountain #817

mooki referenced this pull request 2026-11-15 17:40:00 +00:00

WIP: fix(macos): MoltenVK's precompile and pipelines on Metal #849

mooki commented 2026-11-15 18:08:33 +00:00

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Folded into #849 (fix(macos): MoltenVK's precompile and pipelines on Metal)

Folded into #849 (fix(macos): MoltenVK's precompile and pipelines on Metal)

mooki closed this pull request 2026-11-15 18:08:34 +00:00

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