Robert Allan JamesandClaude Sonnet 5
d8a195b8d8
Found live during identity-heap-capacity testing (2026-09-07, hotplugging Zuse + 8 identities one at a time and measuring the kernel heap arena via a temporary allocator-stats probe, since reverted): every WIREBIND identity attach births two VMs in sequence -- a "console" VM, then the real "user" VM. When the second birth failed (arena fragmentation under concurrent VM load, a separate, not-yet-fixed capacity issue), capsule_wirebind_try_attach() logged the failure and returned, but the console VM that had *already succeeded* was never torn down. It stays live and registered under the identity's username, consuming its own ~228KB of the fixed 4MB kernel heap arena forever -- nothing ever points a real user at it, since WIREBIND only ever hands the caller the user VM's id. This turns every failed identity attach into a permanent net loss of heap rather than a neutral retry: confirmed live that a failed attach left the arena 228,576 bytes worse off than before the attempt, and every subsequent attempt starts from that worse baseline, compounding. Fix: call capsule_vm_kill(username) on the now-orphaned console VM before returning from the failure path -- the same teardown capsule_wirebind_eject()/capsule_wirebind_unclean_detach() already use elsewhere in this file (vm_cleanup() + sf_free(), confirmed live to actually reclaim per-word dictionary allocations, FABRIC-3.md §IX.2/§IX.3). Verified live with the same allocator-stats probe (written, captured, reverted -- not part of this commit): after the fix, a forced user-VM birth failure now returns the arena to exactly its pre-attempt byte count (3,526,256, matching the baseline precisely) instead of leaking 228,576 bytes. Three-arch clean qemu acceptance (single Zuse device, the standard regression case) passed on amd64, aarch64, and riscv64. The underlying capacity/fragmentation question (why the 7th concurrent identity's arena allocation fails at all despite technically-sufficient free bytes) is a separate, open architecture question -- not addressed here. See project memory for the full measured numbers. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_014Ec88YKxxhZGG1RNnune78
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