Struct SpillManager 

pub struct SpillManager { /* private fields */ }

Manages spill file lifecycle for out-of-core processing.

The manager handles:

• Creating unique spill files with prefixes
• Tracking total bytes spilled to disk
• Automatic cleanup of all spill files on drop

By default the spill directory itself outlives the manager (the caller owns it). Per-query callers that pass a unique throwaway directory should chain with_owned_dir so Drop also removes the directory once its files are gone.

Implementations

impl SpillManager

pub fn new(spill_dir: impl Into<PathBuf>) -> Result<Self>

Creates a new spill manager with the given directory.

Creates the directory if it doesn’t exist. The directory is not removed on drop unless with_owned_dir is chained on the result.

Errors

Returns an error if the directory cannot be created.

pub fn with_owned_dir(self) -> Self

Marks the spill directory as owned by this manager so that Drop removes it (non-recursive) after spill files are cleaned up.

Use for per-query spill subdirectories (e.g. <base>/query_<id>/) where leaving the empty directory behind would accumulate over time. The removal is best-effort: if anything unexpected is left in the directory, remove_dir fails and the directory is preserved.

pub fn with_temp_dir() -> Result<Self>

Creates a new spill manager using a system temp directory.

Errors

Returns an error if the temp directory cannot be created.

pub fn spill_dir(&self) -> &Path

Returns the spill directory path.

pub fn create_file(&self, prefix: &str) -> Result<SpillFile>

Creates a new spill file with the given prefix.

The file name format is: {prefix}_{file_id}.spill

Errors

Returns an error if the file cannot be created.

pub fn register_spilled_bytes(&self, bytes: u64)

Registers bytes spilled to disk.

Called by SpillFile when writing completes.

pub fn unregister_spilled_bytes(&self, bytes: u64)

Unregisters bytes when a spill file is deleted.

Called by SpillFile on deletion.

pub fn unregister_file(&self, path: &Path)

Removes a file path from tracking (called when file is deleted).

pub fn spilled_bytes(&self) -> u64

Returns total bytes currently spilled to disk.

pub fn active_file_count(&self) -> usize

Returns the number of active spill files.

pub fn cleanup(&self) -> Result<()>

Cleans up all spill files.

This is called automatically on drop, but can be called manually.

Errors

Returns an error if any file cannot be deleted (continues trying others).

Trait Implementations

impl Debug for SpillManager

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

Formats the value using the given formatter.

impl Drop for SpillManager

fn drop(&mut self)

Executes the destructor for this type.