Safe Haskell	Safe-Inferred
Language	Haskell2010

Ouroboros.Consensus.Storage.ImmutableDB.Impl.Index.Cache

Contents

Environment
Background thread
Operations
- On the primary index
- On the secondary index

Synopsis

data CacheConfig = CacheConfig {
- pastChunksToCache ∷ Word32
- expireUnusedAfter ∷ DiffTime
}
data CacheEnv m blk h
checkInvariants ∷ Word32 → Cached blk → Maybe String
newEnv ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ HasFS m h → ResourceRegistry m → Tracer m TraceCacheEvent → CacheConfig → ChunkInfo → ChunkNo → m (CacheEnv m blk h)
expireUnusedChunks ∷ (HasCallStack, IOLike m) ⇒ CacheEnv m blk h → m Void
close ∷ IOLike m ⇒ CacheEnv m blk h → m ()
restart ∷ (ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → ChunkNo → m ()
appendOffsets ∷ (HasCallStack, Foldable f, IOLike m) ⇒ CacheEnv m blk h → Handle h → f SecondaryOffset → m ()
openPrimaryIndex ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → ChunkNo → AllowExisting → m (Handle h)
readFirstFilledSlot ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → ChunkNo → m (Maybe RelativeSlot)
readOffsets ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk, Traversable t) ⇒ CacheEnv m blk h → ChunkNo → t RelativeSlot → m (t (Maybe SecondaryOffset))
appendEntry ∷ ∀ m blk h. (HasCallStack, ConvertRawHash blk, IOLike m) ⇒ CacheEnv m blk h → ChunkNo → Handle h → Entry blk → m Word64
readAllEntries ∷ ∀ m blk h. (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → SecondaryOffset → ChunkNo → (Entry blk → Bool) → Word64 → IsEBB → m [WithBlockSize (Entry blk)]
readEntries ∷ ∀ m blk h t. (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk, Traversable t) ⇒ CacheEnv m blk h → ChunkNo → t (IsEBB, SecondaryOffset) → m (t (Entry blk, BlockSize))

Environment

data CacheConfig Source #

Constructors

CacheConfig
Fields pastChunksToCache ∷ Word32 Maximum number of past chunks to cache, excluding the current chunk. NOTE: must be > 0 expireUnusedAfter ∷ DiffTime Expire past chunks that haven't been used for `$sel:expireUnusedAfter:CacheConfig` from the cache, regardless the number of past chunks in the cache.

Instances

Instances details

Show CacheConfig Source #
Instance details Defined in Ouroboros.Consensus.Storage.ImmutableDB.Impl.Index.Cache Methods showsPrec ∷ Int → CacheConfig → ShowS # show ∷ CacheConfig → String # showList ∷ [CacheConfig] → ShowS #
Eq CacheConfig Source #
Instance details Defined in Ouroboros.Consensus.Storage.ImmutableDB.Impl.Index.Cache Methods (==) ∷ CacheConfig → CacheConfig → Bool # (/=) ∷ CacheConfig → CacheConfig → Bool #

data CacheEnv m blk h Source #

Environment used by functions operating on the cached index.

checkInvariants Source #

Arguments

∷ Word32	Maximum number of past chunks to cache
→ Cached blk
→ Maybe String

newEnv Source #

Arguments

∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk)
⇒ HasFS m h
→ ResourceRegistry m
→ Tracer m TraceCacheEvent
→ CacheConfig
→ ChunkInfo
→ ChunkNo	Current chunk
→ m (CacheEnv m blk h)

Creates a new CacheEnv and launches a background thread that expires unused past chunks (expireUnusedChunks).

PRECONDITION: $sel:pastChunksToCache:CacheConfig (in CacheConfig) > 0

Background thread

expireUnusedChunks ∷ (HasCallStack, IOLike m) ⇒ CacheEnv m blk h → m Void Source #

Intended to run as a background thread.

Will expire past chunks that haven't been used for $sel:expireUnusedAfter:CacheConfig from the cache.

Operations

close ∷ IOLike m ⇒ CacheEnv m blk h → m () Source #

Stops the background expiration thread.

This operation is idempotent.

restart Source #

Arguments

∷ (ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk)
⇒ CacheEnv m blk h
→ ChunkNo	The new current chunk
→ m ()

Restarts the background expiration thread, drops all previously cached information, loads the given chunk.

PRECONDITION: the background thread expiring unused past chunks must have been terminated.

On the primary index

appendOffsets ∷ (HasCallStack, Foldable f, IOLike m) ⇒ CacheEnv m blk h → Handle h → f SecondaryOffset → m () Source #

openPrimaryIndex ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → ChunkNo → AllowExisting → m (Handle h) Source #

This is called when a new chunk is started, which means we need to update Cached to reflect this.

readFirstFilledSlot ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → ChunkNo → m (Maybe RelativeSlot) Source #

readOffsets ∷ (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk, Traversable t) ⇒ CacheEnv m blk h → ChunkNo → t RelativeSlot → m (t (Maybe SecondaryOffset)) Source #

On the secondary index

appendEntry ∷ ∀ m blk h. (HasCallStack, ConvertRawHash blk, IOLike m) ⇒ CacheEnv m blk h → ChunkNo → Handle h → Entry blk → m Word64 Source #

readAllEntries ∷ ∀ m blk h. (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk) ⇒ CacheEnv m blk h → SecondaryOffset → ChunkNo → (Entry blk → Bool) → Word64 → IsEBB → m [WithBlockSize (Entry blk)] Source #

readEntries ∷ ∀ m blk h t. (HasCallStack, ConvertRawHash blk, IOLike m, StandardHash blk, Typeable blk, Traversable t) ⇒ CacheEnv m blk h → ChunkNo → t (IsEBB, SecondaryOffset) → m (t (Entry blk, BlockSize)) Source #