Struct TreeInfo 

pub struct TreeInfo(/* private fields */);

Compact heap-allocated metadata for BTreeMap.

Holds leaf_count, inter_count, and a growable path-cache stack in one contiguous allocation, decoupled from the BTreeMap struct itself.

Heap memory layout

[TreeInfoHeader | (InterNode<K,V>, u32) × cap]

Initial buffer = one CACHE_LINE_SIZE block; grows by one block per overflow.

Stack memory layout

TreeInfo store either point, or ((entry_idx) << 8) | EMPTY_FLAG.

Because in our scenario iteration with Entry is hot path, to reduce moving cost, we pack entry_idx inside TreeInfo stack or Heap (TreeInfoHeader)

NOTE: we tried enum u8 and NonNull, but rustc does not pack it to usize.

Using NonZeroUsize will optimize Option<BTreeMap>

Trait Implementations

impl Debug for TreeInfo

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

Formats the value using the given formatter.

impl Default for TreeInfo

fn default() -> TreeInfo

Returns the “default value” for a type.

impl Drop for TreeInfo

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl Send for TreeInfo

impl Stats for TreeInfo

impl Sync for TreeInfo