Wasm RAM

[tameware]

Do not request more than 2GB RAM from WASM, its limit. The messages generated on exceeding it are apparently harmless, but best to avoid them.

This change must be totally isolated from the native builds, otherwise it slows them down by ~5%. I'm still trying to figure out why.

[Copilot]

Pull request overview

This PR adds a WASM-specific cap on parallel worker count so DDS doesn’t request more than the practical wasm32 heap limit (~2 GiB), avoiding noisy (but apparently harmless) out-of-memory warnings on large WASM batches while keeping native builds unaffected.

Changes:

• Introduces a small helper (clamp_workers_to_memory_budget) to cap worker count by a total heap budget and per-worker footprint.
• Adds an Emscripten-only parallel_boards_wasm.cpp implementation that applies a worker cap based on THREADMEM_LARGE_DEF_MB and a fixed heap budget.
• Extends system tests to validate the clamp behavior and ensure native builds do not apply the WASM cap.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
library/tests/system/worker_count_test.cpp	Adds unit tests for the new memory-budget clamp and for WASM-vs-native worker count behavior.
library/src/system/worker_memory_budget.hpp	Declares the helper used to cap worker counts by a memory budget (MB).
library/src/system/worker_memory_budget.cpp	Implements the worker-count clamping logic.
library/src/system/parallel_boards_wasm.cpp	WASM-specific parallel boards implementation that applies the heap-based worker cap.
library/src/system/BUILD.bazel	Uses a select() to compile either the native or WASM parallel_boards implementation depending on the build platform.

Comments suppressed due to low confidence (1)

library/src/system/worker_memory_budget.hpp:22

• The @return description currently omits that the result is also capped by the requested worker count; documenting the exact clamp makes the contract clearer.

 * @return workers clamped to max(1, budget_mb / per_worker_mb)

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.