Enum hwlocality::memory::binding::MemoryBindingPolicy

#[repr(i32)]
pub enum MemoryBindingPolicy {
    FirstTouch = 1,
    Bind = 2,
    Interleave = 3,
    NextTouch = 4,
}

Memory binding policy

Not all systems support all kinds of binding. Topology::feature_support() may be used to query the actual memory binding support in the currently used operating system.

Variants

FirstTouch = 1

Allocate each memory page individually on the local NUMA node of the thread that touches it

The given nodeset should usually be Topology::nodeset() so that the touching thread may run and allocate on any node in the system.

On AIX, if the nodeset is smaller, pages are allocated locally (if the local node is in the nodeset) or from a random non-local node (otherwise).

Requires MemoryBindingSupport::first_touch_policy().

Bind = 2

Allocate memory on the specified nodes (most portable option)

The actual behavior may slightly vary between operating systems, especially when (some of) the requested nodes are full. On Linux, by default, the MPOL_PREFERRED_MANY (or MPOL_PREFERRED) policy is used. However, if the STRICT flag is also given, the Linux MPOL_BIND policy is rather used.

Requires MemoryBindingSupport::bind_policy().

Interleave = 3

Allocate memory on the given nodes in an interleaved round-robin manner

The precise layout of the memory across multiple NUMA nodes is OS/system specific.

Interleaving can be useful when threads distributed across the specified NUMA nodes will all be accessing the whole memory range concurrently, since the interleave will then balance the memory references.

Requires MemoryBindingSupport::interleave_policy().

NextTouch = 4

Migrate pages on next touch

For each page bound with this policy, by next time it is touched (and next time only), it is moved from its current location to the local NUMA node of the thread where the memory reference occurred (if it needs to be moved at all).

Requires MemoryBindingSupport::next_touch_policy().

Trait Implementations

impl Arbitrary for MemoryBindingPolicy

Available on crate feature proptest only.

type Parameters = ()

The type of parameters that arbitrary_with accepts for configuration of the generated Strategy. Parameters must implement Default.

type Strategy = Map<Range<usize>, fn(_: usize) -> MemoryBindingPolicy>

The type of Strategy used to generate values of type Self.

fn arbitrary_with(_args: Self::Parameters) -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self). The strategy is passed the arguments given in args.

fn arbitrary() -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self).

impl Clone for MemoryBindingPolicy

fn clone(&self) -> MemoryBindingPolicy

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for MemoryBindingPolicy

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

Formats the value using the given formatter.

impl Default for MemoryBindingPolicy

fn default() -> MemoryBindingPolicy

Returns the “default value” for a type.

impl Display for MemoryBindingPolicy

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

Formats the value using the given formatter.

impl From<MemoryBindingPolicy> for i32

fn from(enum_value: MemoryBindingPolicy) -> Self

Converts to this type from the input type.

impl Hash for MemoryBindingPolicy

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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for MemoryBindingPolicy

fn eq(&self, other: &MemoryBindingPolicy) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Sequence for MemoryBindingPolicy

const CARDINALITY: usize = 4usize

Number of values of type Self.

fn next(&self) -> Option<Self>

Returns value following *self or None if this was the end.

fn previous(&self) -> Option<Self>

Returns value preceding *self or None if this was the beginning.

fn first() -> Option<Self>

Returns the first value of type Self.

fn last() -> Option<Self>

Returns the last value of type Self.

impl TryFrom<i32> for MemoryBindingPolicy

type Error = TryFromPrimitiveError<MemoryBindingPolicy>

The type returned in the event of a conversion error.

fn try_from(number: i32) -> Result<Self, TryFromPrimitiveError<Self>>

Performs the conversion.

impl TryFromPrimitive for MemoryBindingPolicy

type Primitive = i32

type Error = TryFromPrimitiveError<MemoryBindingPolicy>

const NAME: &'static str = "MemoryBindingPolicy"

fn try_from_primitive( number: Self::Primitive ) -> Result<Self, TryFromPrimitiveError<Self>>

impl Copy for MemoryBindingPolicy

impl Eq for MemoryBindingPolicy

impl StructuralPartialEq for MemoryBindingPolicy