org.apache.arrow.memory

Interface AllocationListener

public interface AllocationListener

An allocation listener being notified for allocation/deallocation

It might be called from multiple threads if the allocator hierarchy shares a listener, in which case, the provider should take care of making the implementation thread-safe.

Field Summary

Fields

Modifier and Type	Field and Description
static AllocationListener	NOOP

Method Summary

Modifier and Type	Method and Description
void	onAllocation(long size) Called each time a new buffer is allocated
boolean	onFailedAllocation(long size, AllocationOutcome outcome) Called whenever an allocation failed, giving the caller a chance to create some space in the allocator (either by freeing some resource, or by changing the limit), and, if successful, allowing the allocator to retry the allocation.

Field Detail

NOOP

static final AllocationListener NOOP

Method Detail

onAllocation

void onAllocation(long size)

Called each time a new buffer is allocated

Parameters:

size - the buffer size being allocated

onFailedAllocation

boolean onFailedAllocation(long size,
                           AllocationOutcome outcome)

Called whenever an allocation failed, giving the caller a chance to create some space in the allocator (either by freeing some resource, or by changing the limit), and, if successful, allowing the allocator to retry the allocation.

Parameters:

size - the buffer size that was being allocated

outcome - the outcome of the failed allocation. Carries information of what failed

Returns:

true, if the allocation can be retried; false if the allocation should fail