Robert Allan JamesandClaude Sonnet 5
89d8c08582
Closes FABRIC-2.md's last open §12 Q5 question. fleet_heartbeat_tick_count is fed by every live VM's own vm_tick(), not one VM's, so it was reaching HEARTBEAT_INFERENCE_FREQUENCY (shared/borrowed from the per-VM inference gate) several times faster than intended with more than one VM live - backwards from FABRIC.md §22.4's required ~1000:1 separation. What's actually gated turned out to be low-stakes: vm_physics_tick() (capsule_vm_physics.c:397) is a passive statistics refit - re-sorts a window of past heat-transfer samples and recomputes a median rate estimate. It doesn't move heat or arbitrate capacity. Firing too often just meant a noisier statistic recomputed more frequently than planned, not incorrect behavior. Considered and explicitly rejected: scaling the threshold by live VM count at the check site. That's the first brick of a scheduler - reading fleet state to adjust a rate dynamically - which this project has deliberately avoided building. Implemented instead: STADIUM_CAPACITY_TICK (existing Kconfig symbol, defined but never read by any code path) now gates vm_physics_heartbeat_tick()'s call directly, replacing the borrowed HEARTBEAT_INFERENCE_FREQUENCY. Default bumped 1000 -> 4000, a flat constant picked once for Tripod's known 4-VM topology, same kind of placeholder as every other frequency knob in Kconfig.kernel - not computed from anything at runtime. Renamed fleet_last_inference_tick -> fleet_last_capacity_tick to match. Still one clock, one counter (fleet_heartbeat_tick_count) - just a bigger flat divisor on it. Three-arch QEMU acceptance: all clean to ok>, identical Stadium conservation invariant on all three (resident_sum=43691 reservoir=21845 sum=65536). logs/20260815-093425/amd64, logs/20260815-093521/aarch64, logs/20260815-093641/riscv64. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
capsules/
FORTH personality files loaded by the VM at boot. A capsule is an immutable, content-addressed payload; its XXHash64 hash is its identity. Any mutation changes the hash and the birth protocol rejects the image.
Key files
| File | Type | Purpose |
|---|---|---|
init.4th |
(m) MAMA_INIT |
Default Mama VM personality — loaded at LBN 2048 |
ACL.4th |
user | Word-level ACL system; self-activating at boot |
zuse.4th |
user | Bootstrap superuser; loaded by ACL.4th |
doe.4th |
user | DoE workload words (EXEC-DOE) — opt-in |
init-0.4th … init-9.4th |
(p) |
Numbered personality variants |
init-l8-*.4th |
(p) |
L8 Jacquard mode variants (stable/volatile/diverse/temporal/transition/omni) |
hermes/init.4th |
(p) |
Hermes baby VM personality |
artemis/init.4th |
(p) |
Artemis baby VM personality |
Block namespace
Block ranges are shared across all loaded capsules — collisions cause silent word-definition overwrites.
| Range | Owner |
|---|---|
| 2048–2099 | init.4th |
| 2100–2199 | doe.4th |
| 3000–3999 | workload capsules |
| 4000+ | user-defined (ACL.4th, zuse.4th, …) |
Each block is limited to 1024 bytes. Verify with wc -c before committing.
See also
experiments/bare_metal/README.md— DoE protocols and block namespace rulesdocs/03-architecture/word-acl/DESIGN.md— ACL system designtools/mkcapsule.c— assembles capsules intocapsule_generated.c- Project root