Crate lgalloc

A size-classed file-backed large object allocator.

This library contains types to allocate memory outside the heap, supporting power-of-two object sizes. Each size class has its own memory pool.

Safety

This library is very unsafe on account of unsafe and interacting directly with libc, including Linux extension.

The library relies on memory-mapped files. Users of this file must not fork the process because otherwise two processes would share the same mappings, causing undefined behavior because the mutable pointers would not be unique anymore. Unfortunately, there is no way to tell the memory subsystem that the shared mappings must not be inherited.

Clients must not lock pages (mlock), or need to unlock the pages before returning them to lgalloc.

Structs

• BackgroundWorkerConfig
  Configuration for lgalloc’s background worker.
• FileStats
  Statistics per size class and backing file.
• Handle
  Handle to describe allocations.
• LgAlloc
  Lgalloc configuration
• LgAllocStats
  Statistics about lgalloc’s internal behavior.
• SizeClassStats
  Statistics per size class.

Enums

• AllocError
  Allocation errors

Constants

• VALID_SIZE_CLASS
  Range of valid size classes.

Functions

• allocate
  Allocate a memory area suitable to hold capacity consecutive elements of T.
• deallocate
  Free the memory referenced by handle, which has been obtained from allocate.
• lgalloc_set_config
  Set or update the configuration for lgalloc.
• lgalloc_stats
  Determine global statistics per size class