9.4. Context and idle-fork memory observations

Context and retained idle-fork memory snapshots for runtime diagnostics. Sample on the owning context and publish value copies across threads.

9.4.1. Structures

ContextMemory

Memory sizes in bytes, sampled on the owning context.

Fields:

• heap_used : uint64 - Live context heap bytes.

• heap_reserved : uint64 - Reserved context heap bytes.

• strings_used : uint64 - Live string heap bytes.

• strings_reserved : uint64 - Reserved string heap bytes.

• stack : uint64 - Context stack capacity.

• globals : uint64 - Context global storage.

• native_stack : uint64 - Current Emscripten thread stack capacity, zero elsewhere.

IdleForkMemory

Memory retained by idle forks; active jobs are excluded.

Fields:

• count : uint64 - Retained idle context count.

• memory : ContextMemory - Aggregate context sizes; native_stack is zero.

9.4.2. Context snapshots

• context_idle_forks () : IdleForkMemory

• context_memory () : ContextMemory

context_idle_forks(): IdleForkMemory

Idle job contexts retained by this owner. Join jobs before sampling to include the complete pool. Active forks are excluded rather than reading changing heaps.

context_memory(): ContextMemory

Samples the calling context. Publish the returned value copy across threads.