Struct wasmtime_environ::Tunables

pub struct Tunables {
    pub static_memory_bound: u64,
    pub static_memory_offset_guard_size: u64,
    pub dynamic_memory_offset_guard_size: u64,
    pub dynamic_memory_growth_reserve: u64,
    pub generate_native_debuginfo: bool,
    pub parse_wasm_debuginfo: bool,
    pub interruptable: bool,
    pub consume_fuel: bool,
    pub static_memory_bound_is_maximum: bool,
    pub guard_before_linear_memory: bool,
}

Tunable parameters for WebAssembly compilation.

Fields

static_memory_bound: u64

For static heaps, the size in wasm pages of the heap protected by bounds checking.

static_memory_offset_guard_size: u64

The size in bytes of the offset guard for static heaps.

dynamic_memory_offset_guard_size: u64

The size in bytes of the offset guard for dynamic heaps.

dynamic_memory_growth_reserve: u64

The size, in bytes, of reserved memory at the end of a “dynamic” memory, before the guard page, that memory can grow into. This is intended to amortize the cost of memory.grow in the same manner that Vec<T> has space not in use to grow into.

generate_native_debuginfo: bool

Whether or not to generate native DWARF debug information.

parse_wasm_debuginfo: bool

Whether or not to retain DWARF sections in compiled modules.

interruptable: bool

Whether or not to enable the ability to interrupt wasm code dynamically.

More info can be found about the implementation in crates/environ/src/cranelift.rs. Note that you can’t interrupt host calls and interrupts are implemented through the VMInterrupts structure, or InterruptHandle in the wasmtime crate.

consume_fuel: bool

Whether or not fuel is enabled for generated code, meaning that fuel will be consumed every time a wasm instruction is executed.

static_memory_bound_is_maximum: bool

Whether or not to treat the static memory bound as the maximum for unbounded heaps.

guard_before_linear_memory: bool

Whether or not linear memory allocations will have a guard region at the beginning of the allocation in addition to the end.

Trait Implementations

impl Clone for Tunables

fn clone(&self) -> Tunables

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for Tunables

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Tunables

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl Hash for Tunables

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Serialize for Tunables

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.