Struct SyntheticCachePager 

pub struct SyntheticCachePager { /* private fields */ }

In-memory CachePager used by every test in this crate and by examples/02-twelve-way-parallel/ (when that lands).

Stores pages in a BTreeMap<u32, PageBytes> keyed by physical-page index. allocate_pages returns monotonically increasing indices; write_page inserts; read_page reads.

Clone-able — the inner state is Arc<Mutex<…>> so two clones share the same logical engine. Useful for “fork the in-memory engine; mutate one branch; serialize each; assert dedup.”

Implementations

impl SyntheticCachePager

pub fn new(meta: CacheMeta) -> Self

Construct an empty engine with the given static metadata.

pub fn populate_synthetic(&mut self, n_pages: u32, seed: u64) -> Result<()>

Pre-populate the engine with n_pages deterministic pages and one logical sequence covering them all. Useful for tests / benches.

seed mixes into the per-page fill so different seeds produce different pages (driving CAS divergence) while the same seed produces byte-identical pages (driving CAS dedup).

Trait Implementations

impl CachePager for SyntheticCachePager

fn meta(&self) -> CacheMeta

Static cache metadata (page size, layer count, dtype, …).

fn pause(&mut self) -> Result<()>

Pause the engine so the page table is stable. May be a no-op for adapters that already hold a write-lock during snapshot.

fn resume(&mut self) -> Result<()>

Resume the engine after pause / restore.

fn occupied_pages(&self) -> Vec<u32>

List physical-page indices that currently hold valid data.

fn logical_seqs(&self) -> Vec<LogicalSeq>

Snapshot of every live logical sequence’s page-table mapping.

fn read_page(&self, ix: u32) -> Result<PageBytes>

Read one (K, V) page out of the engine. Implementations return raw bytes of length meta.page_bytes() for each.

fn allocate_pages(&mut self, n: usize) -> Result<Vec<u32>>

Allocate n fresh physical-page slots and return their indices in the order they should be filled. Restore writes pages in this order.

fn write_page(&mut self, ix: u32, page: &PageBytes) -> Result<()>

Write one (K, V) page into the engine at the given physical-page index. The index MUST have been returned by a recent Self::allocate_pages call.

fn install_logical_seqs(&mut self, seqs: &[LogicalSeq]) -> Result<()>

Re-install the per-request logical-seq → page-list mapping after restore. Called once, after all pages have been written.

impl Clone for SyntheticCachePager

fn clone(&self) -> SyntheticCachePager

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SyntheticCachePager

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

Formats the value using the given formatter.