Struct sc_executor_wasmtime::Config

pub struct Config {
    pub heap_pages: u32,
    pub max_memory_pages: Option<u32>,
    pub allow_missing_func_imports: bool,
    pub cache_path: Option<PathBuf>,
    pub semantics: Semantics,
}

Fields

heap_pages: u32

The number of wasm pages to be mounted after instantiation.

max_memory_pages: Option<u32>

The total number of wasm pages an instance can request.

If specified, the runtime will be able to allocate only that much of wasm memory pages. This is the total number and therefore the [heap_pages] is accounted for.

That means that the initial number of pages of a linear memory plus the [heap_pages] should be less or equal to max_memory_pages, otherwise the instance won’t be created.

Moreover, memory.grow will fail (return -1) if the sum of the number of currently mounted pages and the number of additional pages exceeds max_memory_pages.

The default is None.

allow_missing_func_imports: bool

The WebAssembly standard requires all imports of an instantiated module to be resolved, othewise, the instantiation fails. If this option is set to true, then this behavior is overriden and imports that are requested by the module and not provided by the host functions will be resolved using stubs. These stubs will trap upon a call.

cache_path: Option<PathBuf>

A directory in which wasmtime can store its compiled artifacts cache.

semantics: Semantics

Tuning of various semantics of the wasmtime executor.