Safe Haskell	None
Language	GHC2021

Ecluse.Core.Server.Cache.Backend

Description

Optional retention with bounded external operations and backend-owned codecs.

Synopsis

data RetentionBackend k v
data RetentionOperations k v = RetentionOperations {
- roLookup :: (CacheOccupancy -> IO ()) -> Recency -> k -> IO (Maybe v)
- roInsert :: (CacheOccupancy -> IO ()) -> IO () -> k -> v -> IO ()
}
data BackendStorage
- = LocalStorage
- | ExternalStorage Int
data Recency
- = PreserveRecency
- | RefreshRecency
data CacheOccupancy = CacheOccupancy {
- occEntries :: Int
- occBytes :: Int
}
retentionBackend :: BackendStorage -> RetentionOperations k v -> RetentionBackend k v
supportsFullRetention :: BackendStorage -> Bool

Documentation

data RetentionBackend k v Source #

Backend-owned storage, independent of request coalescing and admission.

data RetentionOperations k v Source #

Typed storage operations. Recency is advisory and occupancy reporting is optional. Adapters may report charged bytes and entry counts. These do not measure process or remote heap size.

Constructors

RetentionOperations
Fields roLookup :: (CacheOccupancy -> IO ()) -> Recency -> k -> IO (Maybe v) roInsert :: (CacheOccupancy -> IO ()) -> IO () -> k -> v -> IO ()

data BackendStorage Source #

Local storage cannot retain full metadata, regardless of its capacity.

Constructors

LocalStorage
ExternalStorage Int	External operation deadline, in microseconds, capped by the handle.

Instances

Instances details

Show BackendStorage Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods showsPrec :: Int -> BackendStorage -> ShowS # show :: BackendStorage -> String # showList :: [BackendStorage] -> ShowS #
Eq BackendStorage Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods (==) :: BackendStorage -> BackendStorage -> Bool # (/=) :: BackendStorage -> BackendStorage -> Bool #

data Recency Source #

Whether a probe contributes to eviction recency.

Constructors

PreserveRecency
RefreshRecency

Instances

Instances details

Show Recency Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods showsPrec :: Int -> Recency -> ShowS # show :: Recency -> String # showList :: [Recency] -> ShowS #
Eq Recency Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods (==) :: Recency -> Recency -> Bool # (/=) :: Recency -> Recency -> Bool #

data CacheOccupancy Source #

Entry count and summed accounted bytes after a store mutation.

Constructors

CacheOccupancy
Fields occEntries :: Int occBytes :: Int

Instances

Instances details

Show CacheOccupancy Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods showsPrec :: Int -> CacheOccupancy -> ShowS # show :: CacheOccupancy -> String # showList :: [CacheOccupancy] -> ShowS #
Eq CacheOccupancy Source #
Instance details Defined in Ecluse.Core.Server.Cache.Backend.Internal Methods (==) :: CacheOccupancy -> CacheOccupancy -> Bool # (/=) :: CacheOccupancy -> CacheOccupancy -> Bool #

retentionBackend :: BackendStorage -> RetentionOperations k v -> RetentionBackend k v Source #

Build storage independently of request coalescing. External deadlines cap at one second. Adapters own TTL, bounded decoding, identity validation, and storage representation.

supportsFullRetention :: BackendStorage -> Bool Source #

Only external storage is eligible to retain full metadata.