Struct v8::CreateParams

pub struct CreateParams { /* private fields */ }

Initial configuration parameters for a new Isolate.

Implementations

impl CreateParams

pub fn counter_lookup_callback( self, callback: extern "C" fn(name: *const char) -> *mut i32 ) -> Self

Enables the host application to provide a mechanism for recording statistics counters.

pub fn snapshot_blob(self, data: impl Allocated<[u8]>) -> Self

Explicitly specify a startup snapshot blob.

pub fn array_buffer_allocator( self, array_buffer_allocator: impl Into<SharedPtr<ArrayBufferAllocator>> ) -> Self

The ArrayBuffer::ArrayBufferAllocator to use for allocating and freeing the backing store of ArrayBuffers.

pub fn has_set_array_buffer_allocator(&self) -> bool

Check if array_buffer_allocator has already been called. Useful to some embedders that might want to set an allocator but not overwrite if one was already set by a user.

pub fn external_references(self, ext_refs: impl Allocated<[isize]>) -> Self

Specifies an optional nullptr-terminated array of raw addresses in the embedder that V8 can match against during serialization and use for deserialization. This array and its content must stay valid for the entire lifetime of the isolate.

pub fn allow_atomics_wait(self, value: bool) -> Self

Whether calling Atomics.wait (a function that may block) is allowed in this isolate. This can also be configured via SetAllowAtomicsWait.

pub fn only_terminate_in_safe_scope(self, value: bool) -> Self

Termination is postponed when there is no active SafeForTerminationScope.

pub fn embedder_wrapper_type_info_offsets( self, embedder_wrapper_type_index: int, embedder_wrapper_object_index: int ) -> Self

The following parameters describe the offsets for addressing type info for wrapped API objects and are used by the fast C API (for details see v8-fast-api-calls.h).

pub fn heap_limits(self, initial: usize, max: usize) -> Self

Configures the constraints with reasonable default values based on the provided lower and upper bounds.

By default V8 starts with a small heap and dynamically grows it to match the set of live objects. This may lead to ineffective garbage collections at startup if the live set is large. Setting the initial heap size avoids such garbage collections. Note that this does not affect young generation garbage collections.

When the heap size approaches max, V8 will perform series of garbage collections and invoke the NearHeapLimitCallback. If the garbage collections do not help and the callback does not increase the limit, then V8 will crash with V8::FatalProcessOutOfMemory.

The heap size includes both the young and the old generation.

Arguments

• initial - The initial heap size or zero in bytes
• max - The hard limit for the heap size in bytes

Trait Implementations

impl Debug for CreateParams

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CreateParams

fn default() -> CreateParams

Returns the “default value” for a type.