Struct UnspillableHeadroomPool 

pub struct UnspillableHeadroomPool { /* private fields */ }

See the module docs.

Implementations

impl UnspillableHeadroomPool

pub fn new( inner: Arc<dyn MemoryPool>, pool_size: usize, headroom: usize, ) -> Self

Wrap inner (a pool of pool_size bytes), holding headroom back from spillable consumers.

A headroom of 0, or one at least as large as the pool, disables the ceiling — the wrapper then delegates everything unchanged rather than bounding spillers to nothing, which would deadlock every spilling query.

pub fn spillable_ceiling(&self) -> usize

The ceiling spillable consumers are held to, in bytes.

Trait Implementations

impl Debug for UnspillableHeadroomPool

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

Formats the value using the given formatter.

impl Display for UnspillableHeadroomPool

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

Mirrors FairSpillPool’s form, with the ceiling — this string is what an exhaustion error prints, and “fair(pool_size: 2.3 GB)” alone was not enough to tell q10’s failure apart from a genuinely full pool.

impl MemoryPool for UnspillableHeadroomPool

fn name(&self) -> &str

Return pool name

fn register(&self, consumer: &MemoryConsumer)

Registers a new MemoryConsumer

fn unregister(&self, consumer: &MemoryConsumer)

Records the destruction of a MemoryReservation with MemoryConsumer

fn grow(&self, reservation: &MemoryReservation, additional: usize)

Infallibly grow the provided reservation by additional bytes

fn shrink(&self, reservation: &MemoryReservation, shrink: usize)

Infallibly shrink the provided reservation by shrink bytes

fn try_grow( &self, reservation: &MemoryReservation, additional: usize, ) -> Result<()>

Attempt to grow the provided reservation by additional bytes

fn reserved(&self) -> usize

Return the total amount of memory reserved

fn memory_limit(&self) -> MemoryLimit

Return the memory limit of the pool