Struct CachedObjectStore 

pub struct CachedObjectStore { /* private fields */ }

An ObjectStore wrapper that caches object parts on local disk.

The cache splits each object into fixed-size parts and stores them under a root folder.

Reads tagged by SlateDB as compacted SST reads are served from disk when present and admitted on a miss.

Writes can optionally be admitted via CachedObjectStoreBuilder::with_cache_on_flush and CachedObjectStoreBuilder::with_cache_on_compaction.

All other calls (manifests, WAL, listings) pass through to the wrapped store.

Construct it over the raw backend and pass it to SlateDB as the object store itself:

let cache = CachedObjectStore::builder("/var/slatedb-cache", backend)
    .build()
    .await?;
let db = Db::builder(path, cache).build().await?;

Implementations

impl CachedObjectStore

pub fn builder( root_folder: impl Into<PathBuf>, object_store: Arc<dyn ObjectStore>, ) -> CachedObjectStoreBuilder

Returns a builder for a CachedObjectStore that caches parts of the objects in object_store under root_folder on the local filesystem.

pub async fn load_files_to_cache( &self, file_paths: Vec<Path>, max_bytes: usize, ) -> Result<(), Error>

Loads files into the cache up to a maximum number of bytes.

Fetches each object’s raw bytes from the wrapped store and saves them as cache parts on disk. Can be used to warm up the cache.

The max_bytes budget is applied in path order: loading stops at the first file that does not fit, so order paths by priority.

Fetches are best-effort and failures are logged and skipped.

Trait Implementations

impl Clone for CachedObjectStore

fn clone(&self) -> CachedObjectStore

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CachedObjectStore

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

Formats the value using the given formatter.

impl Display for CachedObjectStore

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

Formats the value using the given formatter.

impl ObjectStore for CachedObjectStore

fn delete_stream( &self, locations: BoxStream<'static, Result<Path>>, ) -> BoxStream<'static, Result<Path>>

Deletion of the cache entries associated with the object being deleted is not atomic with respect to the object deletion from the underlying object store. So for some period of time after the deletion, cached object parts are still visible in the cache. But assuming each object ever created by SlateDB is immutable and has a unique name, this is not a problem.

If eviction is enabled, deletion of the associated cache entries happens asynchronously; when the control returns to the caller, the entries still might be present in the cache. If eviction is off, the deletion happens synchronously; when the control returns to the caller, it is guaranteed no entries present in the cache (assuming no errors happened during the deletion).

fn get_opts<'life0, 'life1, 'async_trait>( &'life0 self, location: &'life1 Path, options: GetOptions, ) -> Pin<Box<dyn Future<Output = Result<GetResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Perform a get request with options

fn put_opts<'life0, 'life1, 'async_trait>( &'life0 self, location: &'life1 Path, payload: PutPayload, opts: PutOptions, ) -> Pin<Box<dyn Future<Output = Result<PutResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Save the provided payload to location with the given options

fn put_multipart_opts<'life0, 'life1, 'async_trait>( &'life0 self, location: &'life1 Path, opts: PutMultipartOptions, ) -> Pin<Box<dyn Future<Output = Result<Box<dyn MultipartUpload>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Perform a multipart upload with options

fn list(&self, prefix: Option<&Path>) -> BoxStream<'static, Result<ObjectMeta>>

List all the objects with the given prefix.

fn list_with_offset( &self, prefix: Option<&Path>, offset: &Path, ) -> BoxStream<'static, Result<ObjectMeta>>

List all the objects with the given prefix and a location greater than offset

fn list_with_delimiter<'life0, 'life1, 'async_trait>( &'life0 self, prefix: Option<&'life1 Path>, ) -> Pin<Box<dyn Future<Output = Result<ListResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

List objects with the given prefix and an implementation specific delimiter. Returns common prefixes (directories) in addition to object metadata.

fn copy_opts<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, from: &'life1 Path, to: &'life2 Path, options: CopyOptions, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Copy an object from one path to another in the same object store.

fn rename_opts<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, from: &'life1 Path, to: &'life2 Path, options: RenameOptions, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Move an object from one path to another in the same object store.

fn get_ranges<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, location: &'life1 Path, ranges: &'life2 [Range<u64>], ) -> Pin<Box<dyn Future<Output = Result<Vec<Bytes>, Error>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Return the bytes that are stored at the specified location in the given byte ranges