3.6 KiB
Resource budget
Measured feasibility baseline
Milestone 004's accepted ESP32-C6 run completed 20 games of 200 updates with two players and eight spectators. Its measured values were 1,000,496 B flash, 38,204 B RAM, 249,616 B minimum free heap, 320 B largest state message, 154 us maximum generation time, and 5,283 us maximum asynchronous delivery-enqueue time. The application partition is 2,097,152 B and LittleFS is 2,031,616 B.
Hard production limits
| Resource | Limit | Basis |
|---|---|---|
| Firmware image | 1,500,000 B | M004 fixed threshold, leaving 597,152 B app-partition reserve |
| LittleFS image | 250,000 B | M004 fixed threshold, leaving 1,781,616 B filesystem reserve |
| Minimum free heap | 96,000 B | M004 fixed threshold; observed minimum was 249,616 B |
| Largest role-safe state JSON | 768 B | Two bounded 80-byte display names plus role-safe game state |
| HTTP JSON request body | 192 B | Largest defined command (join) fits within this bound |
| WebSocket incoming frame | 192 B | hello is the largest defined incoming frame |
| HTTP request target/query | 128 B | /api/state?version=4294967295 is below this bound |
| State generation | 100,000 us | M004 fixed threshold; observed maximum was 154 us |
| State delivery enqueue | 100,000 us | M004 fixed threshold; observed maximum was 5,283 us |
| Pending application commands | 16 | Fixed bounded queue; excess requests return SERVER_BUSY |
| Sessions | 10 | Two players and eight spectators |
| Open HTTP sockets | 12 | Ten clients plus two polling/transport headroom; LWIP is configured for 16 |
No handler may allocate a per-client complete JSON state. It serializes one bounded snapshot at a time into the 768-byte transport buffer.
Per-milestone budget gates
| Milestone | Firmware ceiling | LittleFS ceiling | Heap floor | Required check |
|---|---|---|---|---|
| 006 architecture | 1,080,000 B | 250,000 B | 220,000 B | clean build and host tests |
| 007 game core | 1,180,000 B | 250,000 B | 190,000 B | fleet and rules tests |
| 008 sessions/API | 1,300,000 B | 250,000 B | 150,000 B | role filtering and malformed input |
| 009 transport/UI | 1,420,000 B | 250,000 B | 115,000 B | two players/eight spectators |
| MVP completion | 1,500,000 B | 250,000 B | 96,000 B | repeated on-board game test |
Each gate is a maximum permitted consumption or minimum required remaining heap. A missed gate blocks the next milestone pending a documented decision.
Milestone 024 browser-audio asset measurement
The bounded Web Audio foundation adds web_audio.js: 7,863 B raw and 2,072 B
gzip. The current six compressed web assets total 24,947 B, well below the
250,000 B LittleFS ceiling. The browser performs synthesis locally, so this
change adds no ESP32 RAM allocation, API payload, or firmware-code cost.