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MobileGL/docs/Disaggregated/notes/p4a/ab/main-two-arm.md
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swung0x48 aba329cc53 [Docs] (Disaggregated): P6's plan and contract draft; the working notes move from a local directory into the repository
Two things land together: the plan and contract draft P6 needs before it starts, and the
working notes that until now existed on exactly one machine.

1. P6's plan and contract draft (neither started; not one line of code)

     docs/Disaggregated/P6-SPAWN-PLAN.md      the package plan
     docs/Disaggregated/P6-CONTRACT-DRAFT.md  the contract draft (moves to
                                              MG_Remote/CONTRACT-P6.md when c6 lands)

   The three findings that mattered, all written into the documents:

   a. P6 is SMALLER than its roadmap cell suggests. The transport primitives are already in
      the tree and already tested: SocketDoorbell including hangup detection and the two
      lost-wakeup fences (Doorbell.cpp:211-360, four cases in FdPassingTest), SCM_RIGHTS fd
      passing, ShmSegment::Adopt, and the SurfaceOp / WindowKind schema already defined in
      protocol.fbs. inproc uses a real second shm mapping rather than an alias, and
      SessionRings.h:22-28 says that was done so today is not the first time it runs. P6 is
      assembly plus a control plane plus a process, not "write a socket transport".

   b. The evidence for "P6 is only a transport swap" has EXPIRED. It was bought by P5c, whose
      audit found 59 direct memory accesses in a tree that already looked clean. P5e changed
      the tree again. So the first package, a6, is a read-only audit that writes no code, and
      every contract row that depends on it is marked PENDING a6 rather than decided in
      advance.

   c. P6 does not get a game running on the phone. ANativeWindow* is meaningless in the child,
      and protocol.fbs:186-196's own comment says Android transfers the window out of band -
      that band is P12. P6 lands pbuffer / surfaceless / offscreen, which is what HeadlessGL,
      the split-equivalent lane and trace replay need, and which is exactly what P6's own exit
      gate measures. A real window reaching the server is a named refusal. This gets its own
      section because "P6 is done" would otherwise read as "the game runs now".

   The contract adds rule G: a role may not name a process-local handle. It extends P5c's
   rule E (a role may not name the other role's memory) from memory to identity - EGLDisplay /
   EGLSurface / EGLContext / ANativeWindow* / fd number / pid / mapped address either cross as
   a token this contract defines or they do not cross, and a descriptor crosses only through
   SCM_RIGHTS, where the kernel renumbers it.

   What P5e left for P6 gets its own section. The latch semantics are already designed
   (ARCHITECTURE.md:504) and are copied unchanged. What is new is that after run-ahead the
   client no longer waits while the peer process can DIE: the client holds records that were
   published and will never be applied, and Android's freezer suspends the child without
   closing anything. So slow and dead must be distinguishable WITHOUT a timeout threshold.
   That is P6's only new design; everything else is carriage. It shares a predicate with E1's
   outstanding re-specification (ID-122), and the two should be designed together.

   Two gates carried over from P5e's lessons: G2 requires integration-spawn's test-name set to
   match integration-split's name for name, because a differing set means the lane is quietly
   running less; and the arm-proof gate requires every entry to record the child pid and
   transport=spawn in its OWN private log - ID-124 established that this kind of false green
   really happens, and a spawn lane that actually ran monolith would pass every other gate.
   S2's shape must be settled before it is written, and the document says why: E1 is the
   cautionary case.

2. The working notes move into the repository (docs/Disaggregated/notes/, 415 .md files)

   ROADMAP / CURRENT_STAGE_PROGRESS / MEASUREMENTS cite ruling numbers, audit line numbers and
   the provenance of gate figures from ~/w7/notes/, a directory that exists on one machine and
   is under no version control. A record cited hundreds of times that lives only locally is not
   a record, so it moves in whole, with its directory structure intact.

   Only .md moves. Scripts, run logs, census and gate result JSON, patches, APKs and nm dumps
   stay where they are: they are evidence DATA rather than documents - large, regenerated per
   run, and mostly carrying absolute paths and device serials that mean something only on the
   machine that produced them. The mapping and this split are written in
   docs/Disaggregated/notes/README.md.

   Two exceptions are recorded there too: P6's BRIEF has been promoted to a first-class
   document and keeps no copy under notes/, so the two cannot drift apart; and recovered/ holds
   material salvaged from failed workflow runs, which may duplicate the like-named phase
   directories and is kept because a few of those were the only complete version at the time.

   CI's citation lint takes docs/Disaggregated/*.md only (non-recursive), and notes/ is
   deliberately outside it: those notes' file:line citations were written against their own
   code heads, and resolving them against today's HEAD would fail wholesale - which is not an
   error, it is their correct state as a historical record. To check one, use the revision it
   declares (--rev).

3. Inconsistencies fixed in passing

   - README.md's status line still said P5e was in progress while the stage table already said
     closed.
   - CURRENT_STAGE_PROGRESS's next-step item 1 still listed the exit gate as pending, though
     (a) and (b) were run in the previous commit; rewritten to closed plus the one item that
     actually remains (E1).
   - ROADMAP's P6 row still had the pre-phase plan in three of its cells; it now carries the
     package order, the scope boundary and the two new gates.

Checked with check_doc_citations.py: 125 citations across docs/Disaggregated/*.md, 0 problems.
2026-09-18 23:31:39 -04:00

11 KiB

P2 paired A/B - per-thread CPU per frame (ms), trailing window, push - pull

pin columns: before/after verdict per run (P=PINNED, D=DRIFT = a cluster clamped by thermal management, U=UNPINNED) @ cpuss temperature C p50/p99: the runner's best-of-N repeat (lowest mean wall frame time), trailing tailFrames window, device median rule / nearest-rank p99; 'best' says which repeat

device case backend mode pull p50 push p50 d p50 pull p99 push p99 d p99 frames best pull/push pull acc/draw push acc/draw pin pull pin push
35d0befa improved-transparency-minecraft-26.3 DirectGLES finish 10.797 12.363 +1.566 25.557 27.004 +1.447 200/200 run 1/3 / run 1/3 8.39 6.39 P@47.8/P@50.5 P@50.2/P@50.5
35d0befa improved-transparency-minecraft-26.3 DirectGLES nofinish 10.759 12.431 +1.672 25.406 27.013 +1.607 200/200 run 1/3 / run 1/3 8.39 6.39 P@43.6/P@48.6 P@49.8/P@51.3
35d0befa improved-transparency-minecraft-26.3 DirectVulkan finish 10.729 11.591 +0.862 24.924 25.976 +1.052 200/200 run 3/3 / run 3/3 6.52 6.52 P@52.1/P@50.2 P@52.1/P@53.6
35d0befa improved-transparency-minecraft-26.3 DirectVulkan nofinish 10.671 11.583 +0.912 25.034 26.117 +1.083 200/200 run 2/3 / run 1/3 6.52 6.52 P@49.8/P@52.5 P@50.2/P@53.2
35d0befa minecraft-1.21.4-fabric-iris-bsl-in-world DirectGLES finish 1.702 1.346 -0.356 315.989 316.342 +0.353 123/123 run 3/3 / run 1/3 40.95 39.07 P@50.2/P@52.5 P@45.1/P@49.8
35d0befa minecraft-1.21.4-fabric-iris-bsl-in-world DirectGLES nofinish 1.304 1.946 +0.642 317.280 317.310 +0.030 123/123 run 2/3 / run 2/3 40.95 39.07 P@45.5/P@49.4 P@45.9/P@49.0
35d0befa minecraft-1.21.4-fabric-iris-bsl-in-world DirectVulkan finish 0.722 0.817 +0.095 459.039 447.908 -11.131 123/123 run 1/3 / run 1/3 14.25 14.25 P@44.8/P@50.9 P@44.8/P@50.9
35d0befa minecraft-1.21.4-fabric-iris-bsl-in-world DirectVulkan nofinish 0.763 0.794 +0.031 453.873 451.470 -2.403 123/123 run 3/3 / run 1/3 14.25 14.25 P@45.1/P@51.3 P@45.1/P@49.4
35d0befa minecraft-1.21.4-fabric-sodium-in-world DirectGLES finish 1.285 1.446 +0.161 2.436 2.715 +0.279 200/200 run 2/3 / run 2/3 15.64 13.52 P@44.8/P@47.8 P@50.2/P@50.5
35d0befa minecraft-1.21.4-fabric-sodium-in-world DirectGLES nofinish 1.380 1.440 +0.060 2.455 2.493 +0.038 200/200 run 1/3 / run 3/3 15.64 13.52 P@44.8/P@47.5 P@45.5/P@46.3
35d0befa minecraft-1.21.4-fabric-sodium-in-world DirectVulkan finish 0.961 1.037 +0.076 2.086 2.097 +0.011 200/200 run 2/3 / run 3/3 19.51 19.51 P@47.1/P@51.7 P@51.7/P@52.5
35d0befa minecraft-1.21.4-fabric-sodium-in-world DirectVulkan nofinish 0.944 0.522 -0.422 1.992 1.337 -0.655 200/200 run 1/3 / run 1/3 19.51 19.51 P@45.5/P@49.0 P@50.9/P@52.1
35d0befa minecraft-1.21.4-in-world DirectGLES finish 2.362 2.853 +0.491 5.184 5.683 +0.499 200/200 run 2/3 / run 3/3 9.4 7.44 P@45.5/P@49.8 P@45.1/P@49.8
35d0befa minecraft-1.21.4-in-world DirectGLES nofinish 2.341 2.841 +0.500 5.183 5.633 +0.450 200/200 run 1/3 / run 3/3 9.4 7.44 P@45.5/P@49.8 P@45.1/P@49.4
35d0befa minecraft-1.21.4-in-world DirectVulkan finish 1.966 1.802 -0.164 4.256 4.369 +0.113 200/200 run 1/3 / run 1/3 8.76 8.76 P@45.9/P@49.0 P@45.9/P@49.0
35d0befa minecraft-1.21.4-in-world DirectVulkan nofinish 1.050 1.735 +0.685 2.363 5.902 +3.539 200/200 run 1/3 / run 1/3 8.76 8.76 P@45.5/P@48.6 P@45.9/P@49.4
35d0befa minecraft-1.21.4-rd12-odinlite-in-world DirectGLES finish 8.221 11.253 +3.032 23.081 24.987 +1.906 200/200 run 3/3 / run 1/3 8.08 6.08 P@41.3/P@49.4 P@45.1/P@52.9
35d0befa minecraft-1.21.4-rd12-odinlite-in-world DirectGLES nofinish 8.236 11.204 +2.968 21.918 24.882 +2.964 200/200 run 2/3 / run 1/3 8.08 6.08 P@52.1/P@54.8 P@45.1/P@53.2
3B159D009VZ00000 improved-transparency-minecraft-26.3 DirectGLES finish 9.857 11.404 +1.547 26.125 27.013 +0.888 200/200 run 1/3 / run 1/3 8.39 6.39 P@50.5/P@50.0 P@49.3/P@47.8
3B159D009VZ00000 improved-transparency-minecraft-26.3 DirectGLES nofinish incomplete: push
3B159D009VZ00000 improved-transparency-minecraft-26.3 DirectVulkan nofinish incomplete: pull

GO/NO-GO reading (items 3-4: p50 and p99 per-thread CPU deltas must not be negative for the push arm, i.e. push must not cost more)

Windows where push costs MORE CPU than pull (d > 0):

  • 35d0befa / improved-transparency-minecraft-26.3 / DirectGLES / finish: d p50 +1.566 ms, d p99 +1.447 ms
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectGLES / nofinish: d p50 +1.672 ms, d p99 +1.607 ms
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectVulkan / finish: d p50 +0.862 ms, d p99 +1.052 ms
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectVulkan / nofinish: d p50 +0.912 ms, d p99 +1.083 ms
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectGLES / finish: d p50 -0.356 ms, d p99 +0.353 ms
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectGLES / nofinish: d p50 +0.642 ms, d p99 +0.030 ms
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectVulkan / finish: d p50 +0.095 ms, d p99 -11.131 ms
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectVulkan / nofinish: d p50 +0.031 ms, d p99 -2.403 ms
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectGLES / finish: d p50 +0.161 ms, d p99 +0.279 ms
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectGLES / nofinish: d p50 +0.060 ms, d p99 +0.038 ms
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectVulkan / finish: d p50 +0.076 ms, d p99 +0.011 ms
  • 35d0befa / minecraft-1.21.4-in-world / DirectGLES / finish: d p50 +0.491 ms, d p99 +0.499 ms
  • 35d0befa / minecraft-1.21.4-in-world / DirectGLES / nofinish: d p50 +0.500 ms, d p99 +0.450 ms
  • 35d0befa / minecraft-1.21.4-in-world / DirectVulkan / finish: d p50 -0.164 ms, d p99 +0.113 ms
  • 35d0befa / minecraft-1.21.4-in-world / DirectVulkan / nofinish: d p50 +0.685 ms, d p99 +3.539 ms
  • 35d0befa / minecraft-1.21.4-rd12-odinlite-in-world / DirectGLES / finish: d p50 +3.032 ms, d p99 +1.906 ms
  • 35d0befa / minecraft-1.21.4-rd12-odinlite-in-world / DirectGLES / nofinish: d p50 +2.968 ms, d p99 +2.964 ms
  • 3B159D009VZ00000 / improved-transparency-minecraft-26.3 / DirectGLES / finish: d p50 +1.547 ms, d p99 +0.888 ms

Memo gates, residual bytes and CSO counters (last complete window, push arm)

  • 35d0befa / improved-transparency-minecraft-26.3 / DirectGLES / finish: gates[ers=78960/1367 etl=75258/5069 eub=80327/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=185.36 csom/csob=csom=0/csob=1157 mpr(last window/total)=0/8
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectGLES / nofinish: gates[ers=78960/1367 etl=75258/5069 eub=80327/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=185.36 csom/csob=csom=0/csob=1157 mpr(last window/total)=0/8
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectVulkan / finish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=10740/68928 mpm=67660/1268 mdt=78800/868] resid=185.36 csom/csob=csom=0/csob=1157 mpr(last window/total)=0/0
  • 35d0befa / improved-transparency-minecraft-26.3 / DirectVulkan / nofinish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=10740/68928 mpm=67660/1268 mdt=78800/868] resid=185.36 csom/csob=csom=0/csob=1157 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectGLES / finish: gates[ers=113/133 etl=80/166 eub=246/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=370.67 csom/csob=csom=1/csob=122 mpr(last window/total)=0/2
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectGLES / nofinish: gates[ers=113/133 etl=80/166 eub=246/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=370.67 csom/csob=csom=1/csob=122 mpr(last window/total)=0/2
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectVulkan / finish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/177 mpm=86/91 mdt=81/96] resid=370.67 csom/csob=csom=1/csob=122 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-fabric-iris-bsl-in-world / DirectVulkan / nofinish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/177 mpm=86/91 mdt=81/96] resid=370.67 csom/csob=csom=1/csob=122 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectGLES / finish: gates[ers=81/859 etl=244/696 eub=940/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=171.8 csom/csob=csom=2/csob=811 mpr(last window/total)=0/1
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectGLES / nofinish: gates[ers=81/859 etl=244/696 eub=940/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=171.8 csom/csob=csom=2/csob=811 mpr(last window/total)=0/1
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectVulkan / finish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/657 mpm=109/548 mdt=0/657] resid=171.8 csom/csob=csom=2/csob=811 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-fabric-sodium-in-world / DirectVulkan / nofinish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/657 mpm=109/548 mdt=0/657] resid=171.8 csom/csob=csom=2/csob=811 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-in-world / DirectGLES / finish: gates[ers=6020/1850 etl=6411/1459 eub=7870/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=178.31 csom/csob=csom=2/csob=1719 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-in-world / DirectGLES / nofinish: gates[ers=6020/1850 etl=6411/1459 eub=7870/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=178.31 csom/csob=csom=2/csob=1719 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-in-world / DirectVulkan / finish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/7278 mpm=6030/1248 mdt=5928/1350] resid=178.31 csom/csob=csom=2/csob=1719 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-in-world / DirectVulkan / nofinish: gates[ers=0/0 etl=0/0 eub=0/0 mfp=0/7278 mpm=6030/1248 mdt=5928/1350] resid=178.31 csom/csob=csom=2/csob=1719 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-rd12-odinlite-in-world / DirectGLES / finish: gates[ers=16038/224 etl=16104/158 eub=16262/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=162.91 csom/csob=csom=0/csob=209 mpr(last window/total)=0/0
  • 35d0befa / minecraft-1.21.4-rd12-odinlite-in-world / DirectGLES / nofinish: gates[ers=16038/224 etl=16104/158 eub=16262/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=162.91 csom/csob=csom=0/csob=209 mpr(last window/total)=0/0
  • 3B159D009VZ00000 / improved-transparency-minecraft-26.3 / DirectGLES / finish: gates[ers=78960/1367 etl=75258/5069 eub=80327/0 mfp=0/0 mpm=0/0 mdt=0/0] resid=185.36 csom/csob=csom=0/csob=1157 mpr(last window/total)=0/8
  • 3B159D009VZ00000 / improved-transparency-minecraft-26.3 / DirectGLES / nofinish: gates[-] resid=- csom/csob=-/- mpr(last window/total)=-/None