Struct CacheLog

pub struct CacheLog { /* private fields */ }

CacheLog keeps track of the original and current values of each key accessed. By tracking original values, we can detect and eliminate write patterns where a key is changed temporarily and then reset to its original value

Implementations

impl CacheLog

pub fn with_capacity(capacity: usize) -> CacheLog

impl CacheLog

pub fn take_writes(self) -> Vec<(CacheKey, Option<CacheValue>)>

pub fn get_value(&self, key: &CacheKey) -> ValueExists

Returns a value corresponding to the key.

pub fn add_read( &mut self, key: CacheKey, value: Option<CacheValue>, ) -> Result<(), ReadError>

The first read for a given key is inserted in the cache. For an existing cache entry checks if reads are consistent with previous reads/writes.

pub fn add_write(&mut self, key: CacheKey, value: Option<CacheValue>)

Adds a write entry to the cache.

pub fn merge_left(&mut self, rhs: CacheLog) -> Result<(), MergeError>

Merges two cache logs in a way that preserves the first read (from self) and the last write (from rhs) for the same key in both caches. The merge succeeds if the first read in the right cache for a key ‘k’ is consistent with the last read/write in the self cache.

Example:

Cache1: Cache2: k1 => v1 k1 => v1’ k2 => v2 k3 => v3

Merged Cache: k1 => v1.merge(v1’) <- preserves the first read and the last write for ‘k1’ k2 => v2 k3 => v3

pub fn merge_writes_left(&mut self, rhs: CacheLog) -> Result<(), MergeError>

pub fn merge_reads_left(&mut self, rhs: CacheLog) -> Result<(), MergeError>

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

Trait Implementations

impl Default for CacheLog

fn default() -> CacheLog

Returns the “default value” for a type.

impl From<StorageInternalCache> for CacheLog

fn from(val: StorageInternalCache) -> Self

Converts to this type from the input type.