Fields

• cdbImmutableDB ∷ !(ImmutableDB m blk)
   
• cdbVolatileDB ∷ !(VolatileDB m blk)
   
• cdbLgrDB ∷ !(LgrDB m blk)
   
• cdbChain ∷ !(StrictTVar m (AnchoredFragment (Header blk)))

  Contains the current chain fragment.

  INVARIANT: the anchor point of this fragment is the tip of the ImmutableDB. This implies that this fragment never contains any blocks that are stored in the immutable DB.

  Note that this fragment might be shorter than k headers when the whole chain is shorter than k or in case of corruption of the VolatileDB.

  Note that this fragment might also be longer than k headers, because the oldest blocks from the fragment might not yet have been copied from the VolatileDB to the ImmutableDB.

  The anchor point of this chain should be the most recent "immutable" block according to the protocol, i.e., a block that cannot be rolled back.

  Note that the "immutable" block isn't necessarily at the tip of the ImmutableDB, but could temporarily still be on the in-memory chain fragment. When the background thread that copies blocks to the ImmutableDB has caught up, the "immutable" block will be at the tip of the ImmutableDB again.

  Note that the "immutable" block might be less than k blocks from our tip in case the whole chain is shorter than k or in case of corruption of the VolatileDB.

  Note that the "immutable" block will never be more than k blocks back, as opposed to the anchor point of cdbChain.

• cdbTentativeState ∷ !(StrictTVar m (TentativeHeaderState blk))
   
• cdbTentativeHeader ∷ !(StrictTVar m (StrictMaybe (Header blk)))

  The tentative header, for diffusion pipelining.

  INVARIANT: It fits on top of the current chain, and its body is not known to be invalid, but might turn out to be.

• cdbIterators ∷ !(StrictTVar m (Map IteratorKey (m ())))

  The iterators.

  This maps the IteratorKeys of each open Iterator to a function that, when called, closes the iterator. This is used when closing the ChainDB: the open file handles used by iterators can be closed, and the iterators themselves are closed so that it is impossible to use an iterator after closing the ChainDB itself.

• cdbFollowers ∷ !(StrictTVar m (Map FollowerKey (FollowerHandle m blk)))

  The followers.

  A follower is open iff its FollowerKey is this Map.

  INVARIANT: the followerPoint of each follower is withinFragmentBounds of the current chain fragment (retrieved cdbGetCurrentChain, not by reading cdbChain directly).

• cdbTopLevelConfig ∷ !(TopLevelConfig blk)
   
• cdbInvalid ∷ !(StrictTVar m (WithFingerprint (InvalidBlocks blk)))

  See the docstring of InvalidBlocks.

  The Fingerprint changes every time a hash is added to the map, but not when hashes are garbage-collected from the map.

• cdbNextIteratorKey ∷ !(StrictTVar m IteratorKey)
   
• cdbNextFollowerKey ∷ !(StrictTVar m FollowerKey)
   
• cdbCopyFuse ∷ !(Fuse m)
   
• cdbChainSelFuse ∷ !(Fuse m)
   
• cdbTracer ∷ !(Tracer m (TraceEvent blk))
   
• cdbRegistry ∷ !(ResourceRegistry m)

  Resource registry that will be used to (re)start the background threads, see cdbBgThreads.

• cdbGcDelay ∷ !DiffTime

  How long to wait between copying a block from the VolatileDB to ImmutableDB and garbage collecting it from the VolatileDB

• cdbGcInterval ∷ !DiffTime

  Minimum time between two garbage collections. Is used to batch garbage collections.

• cdbKillBgThreads ∷ !(StrictTVar m (m ()))

  A handle to kill the background threads.

• cdbCheckInFuture ∷ !(CheckInFuture m blk)
   
• cdbChainSelQueue ∷ !(ChainSelQueue m blk)

  Queue of blocks that still have to be added.

• cdbFutureBlocks ∷ !(StrictTVar m (FutureBlocks m blk))

  Blocks from the future

  Blocks that were added to the ChainDB but that were from the future according to CheckInFuture, without exceeding the clock skew (inFutureExceedsClockSkew). Blocks exceeding the clock skew are considered to be invalid (InFutureExceedsClockSkew) and will be added cdbInvalid.

  Whenever a block is added to the ChainDB, we first trigger chain selection for all the blocks in this map so that blocks no longer from the future can get adopted. Note that when no blocks are added to the ChainDB, we will not actively trigger chain selection for the blocks in this map.

  The number of blocks from the future is bounded by the number of upstream peers multiplied by the max clock skew divided by the slot length.

• cdbLoE ∷ LoE (m (AnchoredFragment (Header blk)))

  Configure the Limit on Eagerness. If this is LoEEnabled, it contains an action that returns the LoE fragment, which indicates the latest rollback point, i.e. we are not allowed to select a chain from which we could not switch back to a chain containing it. The fragment is usually anchored at a recent immutable tip; if it does not, it will conservatively be treated as the empty fragment anchored in the current immutable tip.

Fields

• intCopyToImmutableDB ∷ m (WithOrigin SlotNo)

  Copy the blocks older than k from to the VolatileDB to the ImmutableDB and update the in-memory chain fragment correspondingly.

  The SlotNo of the tip of the ImmutableDB after copying the blocks is returned. This can be used for a garbage collection on the VolatileDB.

• intGarbageCollect ∷ SlotNo → m ()

  Perform garbage collection for blocks <= the given SlotNo.

• intUpdateLedgerSnapshots ∷ m ()

  Write a new LedgerDB snapshot to disk and remove the oldest one(s).

• intAddBlockRunner ∷ m Void

  Start the loop that adds blocks to the ChainDB retrieved from the queue populated by addBlock. Execute this loop in a separate thread.

• intKillBgThreads ∷ StrictTVar m (m ())

  A handle to kill the background threads.

Fields

• fhChainType ∷ ChainType

  Whether we follow the tentative chain.

• fhSwitchFork ∷ Point blk → Set (Point blk) → STM m ()

  When we have switched to a fork, all open Followers must be notified.

• fhClose ∷ m ()

  When closing the ChainDB, we must also close all open Followers, as they might be holding on to resources.

  Call fhClose will release the resources used by the Follower.

  NOTE the Follower is not removed from cdbFollowers. (That is done by closeAllFollowers).

Fields

• invalidBlockReason ∷ !(InvalidBlockReason blk)
   
• invalidBlockSlotNo ∷ !SlotNo
   

Fields

• blockPunish ∷ !(InvalidBlockPunishment m)

  Executed immediately upon determining this block or one from its prefix is invalid.

• blockToAdd ∷ !blk
   
• varBlockWrittenToDisk ∷ !(StrictTMVar m Bool)

  Used for the blockWrittenToDisk field of AddBlockPromise.

• varBlockProcessed ∷ !(StrictTMVar m (AddBlockResult blk))

  Used for the blockProcessed field of AddBlockPromise.

Fields

• newTipPoint ∷ RealPoint blk

  The new tip of the current chain.

• newTipEpoch ∷ EpochNo

  The epoch of the new tip.

• newTipSlotInEpoch ∷ Word64

  The slot in the epoch, i.e., the relative slot number, of the new tip.

• newTipTrigger ∷ RealPoint blk

  The new tip of the current chain (newTipPoint) is the result of performing chain selection for a trigger block (newTipTrigger). In most cases, we add a new block to the tip of the current chain, in which case the new tip is the trigger block.

  However, this is not always the case. For example, with our current chain being A and having a disconnected C lying around, adding B will result in A -> B -> C as the new chain. The trigger B /= the new tip C.

• newTipSelectView ∷ SelectView (BlockProtocol blk)

  The SelectView of the new tip. It is guaranteed that

  Just newTipSelectView > oldTipSelectView

  True

• oldTipSelectView ∷ Maybe (SelectView (BlockProtocol blk))

  The SelectView of the old, previous tip. This can be Nothing when the previous chain/tip was Genesis.

Fields

• (Point blk)

  Point at which the follower is

• (WithOrigin SlotNo)

  Slot number at the tip of the ImmutableDB

Fields

• (Point blk)

  Point at which the follower is

• (WithOrigin SlotNo)

  Slot number at the tip of the ImmutableDB

Fields

• (Point blk)

  Immutable tip

• (Point blk)

  Tip of the current chain

Fields

• (Point blk)

  Immutable tip

• (Point blk)

  Tip of the current chain

Fields

• (Point blk)

  Immutable tip

• ChunkNo

  Chunk number of the immutable tip

Fields

• (AnchoredFragment (Header blk))

  Candidate chain containing headers from the future

• [Header blk]

  Headers from the future, not exceeding clock skew

Fields

• (AnchoredFragment (Header blk))

  Candidate chain containing headers from the future

• [Header blk]

  Headers from the future, exceeding clock skew