Struct ColdStorageManager 

pub struct ColdStorageManager { /* private fields */ }

Policy-driven manager that tracks blocks across four storage tiers and migrates them according to access recency.

Implementations

impl ColdStorageManager

pub fn new(policy: TierPolicy) -> Self

Create a new manager with the supplied tier policy.

pub fn register_block(&mut self, cid: &str, size: u64, now: u64)

Register a previously unknown block. If the CID is already known this is a no-op — use access_block to refresh an existing entry.

pub fn access_block(&mut self, cid: &str, now: u64) -> bool

Record an access to the block identified by cid.

Updates last_accessed and increments access_count. Returns false when the CID is not tracked by this manager.

pub fn evaluate_migration( &self, block: &TieredBlock, now: u64, ) -> Option<StorageTier>

Evaluate whether block should be migrated to a colder tier given the current timestamp.

Returns Some(target_tier) when migration is warranted, None otherwise.

pub fn migrate_block( &mut self, cid: &str, target: StorageTier, now: u64, ) -> bool

Migrate a single block to target tier.

• Records archived_at when entering Cold or Frozen.
• Simulates a compression ratio (using the CID checksum as a deterministic surrogate) when compress_cold is set and the block enters Cold or Frozen.

Returns false when the CID is not tracked.

pub fn run_migration_pass(&mut self, now: u64) -> usize

Scan every tracked block and migrate any that are eligible according to the current policy. Returns the number of blocks migrated.

pub fn blocks_in_tier(&self, tier: &StorageTier) -> Vec<&TieredBlock>

Return references to all blocks currently in the specified tier.

pub fn get_block(&self, cid: &str) -> Option<&TieredBlock>

Retrieve metadata for a single block by CID.

pub fn policy(&self) -> &TierPolicy

Return the active tier policy.

pub fn unfreeze(&mut self, cid: &str) -> bool

Move a Frozen block back to Cold.

This is the only supported “warming” operation. The block’s archived_at timestamp is preserved. Returns false when the CID is not tracked or is not currently Frozen.

pub fn stats(&self) -> &ColdStorageStats

Return a reference to the current statistics snapshot.

Note: stats are maintained incrementally; call rebuild_stats if you suspect drift.

pub fn rebuild_stats(&mut self)

Recompute all statistics from scratch by iterating every tracked block.

Use this to correct any accumulator drift, e.g. after bulk operations.

pub fn remove_block(&mut self, cid: &str) -> bool

Remove a block from tracking entirely.

Returns false when the CID was not found.