Struct BlockMigrationPlanner 

pub struct BlockMigrationPlanner { /* private fields */ }

Block migration planner: registers blocks, creates plans, executes them, and provides scheduling and defragmentation helpers.

Implementations

impl BlockMigrationPlanner

pub fn new() -> Self

Create a planner with default configuration.

pub fn with_config(config: BmpPlannerConfig) -> Self

Create a planner with the supplied configuration.

pub fn config(&self) -> &BmpPlannerConfig

Return a reference to the current configuration.

pub fn set_config(&mut self, config: BmpPlannerConfig)

Replace the configuration.

pub fn register_block( &mut self, id: BmpBlockId, size_bytes: u64, src_node: impl Into<String>, tier: u8, access_frequency: f64, )

Register a new block (or overwrite if it already exists).

pub fn update_access(&mut self, id: &BmpBlockId) -> Result<(), BmpError>

Record an access event for a block, bumping last_accessed and applying a simple exponential-moving-average update to access_frequency.

pub fn pin(&mut self, id: &BmpBlockId) -> Result<(), BmpError>

Pin a block so it will not be selected for automatic migration.

pub fn unpin(&mut self, id: &BmpBlockId) -> Result<(), BmpError>

Unpin a previously pinned block.

pub fn block_meta(&self, id: &BmpBlockId) -> Option<&BmpBlockMeta>

Return a reference to a block’s metadata, or None if not registered.

pub fn block_count(&self) -> usize

Number of currently registered blocks.

pub fn create_plan( &mut self, block_ids: Vec<BmpBlockId>, dst_node: impl Into<String>, priority: u32, ) -> Result<BmpPlanId, BmpError>

Create a migration plan for the given blocks.

The src_node is inferred from the first block’s current location; if the list spans multiple source nodes the first one wins (callers should group by node before creating plans when that matters).

Returns Err if any block is pinned or if any block is not registered.

pub fn cancel_plan(&mut self, plan_id: BmpPlanId) -> Result<(), BmpError>

Cancel a pending plan. Plans that are already InProgress, Completed, Failed, or Cancelled cannot be cancelled again.

pub fn execute_plan( &mut self, plan_id: BmpPlanId, ) -> Result<BmpExecutionResult, BmpError>

Execute a migration plan.

Each block is migrated in sequence; a simulated success/failure decision is made via xorshift64 (roughly 90 % success when !dry_run). In dry_run mode all blocks succeed without moving.

pub fn schedule_migrations( &mut self, policy: BmpPriorityPolicy, max_plans: usize, ) -> Result<Vec<BmpPlanId>, BmpError>

Automatically select blocks that need migration and create plans for them.

“Needing migration” means the block has a dst_node already set, or is unpinned and in a non-zero tier (tier > 0 → candidate for promotion). Up to max_plans plans are created, each containing a single block, ordered according to policy.

pub fn run_batch_migration( &mut self, policy: BmpPriorityPolicy, batch_size: usize, ) -> BmpBatchResult

Create up to batch_size plans using policy and execute them all, respecting max_concurrent_migrations.

pub fn defragment_plan(&mut self, nodes: &[String]) -> Vec<BmpPlanId>

Generate plans to balance blocks evenly across the supplied nodes.

Blocks that are already on the least-loaded node (or are pinned) are skipped. The target is total_blocks / nodes.len() per node. Returns Vec<BmpPlanId> of all newly created plans.

pub fn migration_stats(&self) -> BmpPlannerStats

Compute and return aggregate statistics.

pub fn plan_count(&self) -> usize

Return the number of plans in the planner.

pub fn plan(&self, plan_id: BmpPlanId) -> Option<&BmpMigrationPlan>

Return a reference to a plan, or None.

pub fn plans_iter(&self) -> impl Iterator<Item = &BmpMigrationPlan>

Iterate over all plans.

pub fn recent_records(&self, n: usize) -> Vec<&BmpMigrationRecord>

Return the most recent n log records.

pub fn log_len(&self) -> usize

Total number of records in the execution log.

Trait Implementations

impl Default for BlockMigrationPlanner

fn default() -> Self

Returns the “default value” for a type.