LithosAnanake/experiments/bare_metal

Bare-Metal DoE Experiment

This directory holds data and analysis from the LithosAnanke kernel's Design of Experiments (DoE) runs — blind full-factorial 2⁴ experiments that measure the L8 Jacquard mode selector's effect on the Steady-State Machine across all three supported architectures (amd64, aarch64, riscv64).

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Directory Layout

experiments/bare_metal/
├── runs/          ← timestamped canonical CSVs from every acceptance run
├── latest/        ← arch-named copies of the most recent run (human-readable)
│   ├── amd64.csv
│   ├── aarch64.csv
│   └── riscv64.csv
└── analysis/
    ├── charts/    ← generated SVG/PNG charts
    ├── report/    ← timestamped LaTeX / Markdown reports
    └── tables/    ← generated summary tables

runs/ is the canonical archive. latest/ is the eyeball-friendly shortcut — always the most recent run per architecture, overwritten on each new run.

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Running the DoE

The DoE runs automatically when the kernel boots because init.4th calls it. The standard acceptance command runs all three architectures sequentially:

make -f Makefile.starkernel ARCH=amd64   clean qemu
make -f Makefile.starkernel ARCH=aarch64 clean qemu
make -f Makefile.starkernel ARCH=riscv64 clean qemu

Each run executes 48 trials (16 L8 configs × 3 reps, Fisher-Yates shuffled), captures ~1.27 million heartbeat rows per architecture, and writes two files:

File	Path
Timestamped canonical CSV	experiments/bare_metal/runs/doe-<arch>-<YYYYMMDD-HHMMSS>.csv
Latest convenience copy	experiments/bare_metal/latest/<arch>.csv

Run architectures sequentially, never in parallel. All three QEMU instances use accel=tcg (software emulation). Concurrent runs compete for host CPU and corrupt the timing signal that the DoE is measuring.

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Disabling the DoE

To boot into the REPL without running the experiment, comment out the last two lines of capsules/init.4th:

Block 2049
( first init.4th )
: STAR 42 EMIT ;
: STARS 0 DO STAR LOOP ;
: MARGIN 30 SPACES ;
: BAR MARGIN 5 STARS CR ;
: BLIP MARGIN STAR CR ;
: F CR BAR BLIP BAR BLIP BLIP CR ;
( S" Hermes" BIRTH )
( S" Artemis" BIRTH )
( S" doe.4th" EXEC   )   ← comment this out
( 123456 3 L8-DOE    )   ← comment this out

The kernel will boot to the ok> REPL with no experiment running. Commenting both lines leaves doe.4th unloaded so none of its words (L8-DOE, WL-NAME, etc.) are defined, which is the cleanest state for interactive sessions.

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Changing the Seed and Rep Count

The DoE entry point is L8-DOE ( seed reps -- ). The call in init.4th is:

123456 3 L8-DOE

• Seed — any non-zero integer. The same seed always produces the same shuffled run order, so results are reproducible. Change the seed to explore a different permutation; different seeds are statistically equivalent but verify shuffle-independence.

• Reps — trials per L8 configuration (1–200). 3 reps × 16 configs = 48 runs, which takes roughly 25–30 minutes per architecture under TCG. Increase for higher statistical power; decrease for quick smoke checks.

( quick smoke check — 1 rep, 16 runs total )
42 1 L8-DOE

( full study — 10 reps, 160 runs )
987654 10 L8-DOE

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What Are Capsules?

A capsule is a named blob of FORTH-79 source text stored in capsules/. The kernel's EXEC word loads a capsule by filename and interprets it as FORTH source. BIRTH (commented out in init.4th) would instead spawn an isolated child VM whose sole personality is that capsule's code.

There are two roles:

Role	Who uses it	What it does
Init capsule	Mama VM at boot	Defines the VM's vocabulary and behavior
Workload capsule	DoE machinery	Provides a computational task to time

init.4th is the Mama VM's init capsule — executed exactly once at kernel boot, and the only file mkcapsule special-cases by exact filename as the active MAMA_INIT capsule. The numbered files (workload-0.4th … workload-9.4th) and the L8 variant files (init-l8-*.4th) are alternate personality capsules, not a workload dispatched by doe.4th's own DoE — doe.4th generates its own synthetic arithmetic workload internally (DOE-WORK) and has no pluggable per-workload dispatch table today. To exercise one of the numbered capsules' own workload, substitute it in as the boot's init.4th (e.g. cp capsules/workload-3.4th capsules/init.4th before building) rather than wiring it into doe.4th.

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.4th File Structure

Every .4th file must follow StarForth's block format. The block system maps source text to logical blocks; the Block NNNN header tells the loader which block slot to fill.

Mandatory rules:

1. The first line of each logical block must be Block NNNN (capital B, single space, decimal integer).
2. Block numbers must be unique within a single capsule file, and must fall in [2048, 5120).
3. Blocks are loaded in file order and executed top-to-bottom.
4. Each block can hold at most 16 content lines, each at most 64 characters long (validate_forth_blocks in tools/mkcapsule.c, corrected 2026-09-19 against the tool itself — not a 1024-byte budget: 8 lines of 128 characters is 1024 bytes and still fails, since the limit is enforced per-line and per-line-count, not as a total byte count). Verify with mkcapsule --lint capsules/, not wc -c.
5. Comments use ( ... ) — parentheses with spaces inside.
6. Word definitions use : NAME ... ; — standard FORTH-79.

Minimal capsule skeleton:

Block 3100
( My capsule description )

: MY-WORD ( -- )
  42 . CR ;

MY-WORD

Multi-block capsule:

Block 3100
( Block 1: helpers )
: HELPER ( n -- n*2 ) 2 * ;

Block 3101
( Block 2: main logic )
: MAIN ( -- )
  10 0 DO I HELPER . CR LOOP ;

MAIN

The block number namespace is shared across all loaded capsules. Convention used in this repository:

Range	Contents
2048–2099	init.4th (Mama VM boot sequence)
2100–2199	doe.4th (DoE machinery)
3000–3999	Reserved for user-defined workload capsules (see below)
4000+	User-defined capsules

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Adding a Custom Workload Capsule

Step 1 — Create the file.

Add capsules/my-workload.4th using block numbers in the 4000+ range:

Block 4000
( my-workload.4th - description of what this measures )

: MY-COMPUTE ( n -- )
  0 SWAP 0 DO I 3 * + LOOP DROP ;

Block 4001
( main entry point )
: RUN-MY-WORKLOAD ( -- )
  500 0 DO I MY-COMPUTE LOOP ;

RUN-MY-WORKLOAD

The last line should execute the workload so EXEC runs it immediately when the capsule is loaded.

Step 2 — Run it.

doe.4th has no pluggable workload dispatch table today — its own factorial (entropy/CV/temporal-decay/stability × reps) drives a single self-contained synthetic workload (DOE-WORK, Block 2103), not a file picked from a list. To measure your own workload's physics behavior instead, run it standalone as the boot's own capsule rather than trying to wire it into doe.4th's factorial:

cp capsules/my-workload.4th capsules/init.4th   # substitutes it in
make -f Makefile.starkernel ARCH=amd64 clean qemu

(mkcapsule special-cases the exact filename init.4th as the one capsule flagged MAMA_INIT and loaded at boot — this is genuinely a substitution, not a selection from a list, so restore the real init.4th afterward, e.g. git checkout capsules/init.4th.)

Your workload's heartbeat rows will appear in the CSV the same way any boot's do — match by the DOE-RUN marker lines described below, once your capsule's own trial-loop word emits one the same way doe.4th's does.

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CSV Format

Each row emitted by the [HADES][DOE ] serial tag is one heartbeat tick during a workload execution. Extract with:

grep -aP '\[HADES\]\[DOE \]' logs2/qemu-amd64-<timestamp>.log \
  | sed 's/.*\[DOE \] //' > my.csv

Columns (15 total):

#	Name	Type	Description
1	tick_number	uint32	Monotonic heartbeat counter
2	elapsed_ns	uint64	Nanoseconds since run start
3	tick_interval_ns	uint64	Interval from prior tick
4	cache_hits_delta	uint32	Hot-words cache hits this tick
5	bucket_hits_delta	uint32	Bucket hits this tick
6	word_executions_delta	uint32	Words executed this tick
7	hot_word_count	uint64	Words with heat ≥ threshold
8	avg_word_heat_q48	uint64	Mean heat (raw Q48.16 integer)
9	window_width	uint32	L8's target rolling window size
10	actual_window_size	uint32	True analysis width: min(total_executions, window_width)
11	predicted_label_hits	uint32	ANOVA early-exit confirmations (L8 validation signal)
12	jitter_bits	uint64	Estimated jitter (IEEE 754 bit pattern)
13	apic_ticks	uint64	APIC timer monotonic count
14	time_trust_q48	uint64	Time-trust score (Q48.16)
15	variance_q48	uint64	Timing variance (Q48.16)

avg_word_heat_q48 is a raw fixed-point integer. To convert to a human-readable heat value: avg_word_heat = avg_word_heat_q48 / 65536.0.

jitter_bits is the IEEE 754 double-precision bit pattern of the jitter in nanoseconds. In R: readBin(as.raw(…), "double"). In Python: struct.unpack('d', struct.pack('Q', n))[0].

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Interpreting predicted_label_hits

This column is the feedback-loop closure signal.

Each non-zero value means the inference engine ran ANOVA on the current execution window and confirmed the L8 selector's config choice correlated with the subsequent execution pattern — an "early exit" because the statistical test converged without needing all data.

• High rate → L8 chose well; the system settled quickly into a stable regime.
• Low rate → L8 is still searching; the workload is novel or transient.
• Zero throughout → The workload ended before the inference engine had enough data, or the window is too small to trigger ANOVA.

This is the metric that closes the loop between "L8 made a choice" and "that choice was actually validated by what the VM did next."