The block index now tracks the set of dirty block nodes with status
changes that haven't been persisted and flushes the changes to the DB
at the appropriate times.
Currently only the blocks in the active chain are loaded into the
block index on initialization. This instead iterates over the entire
block index bucket in LevelDB and loads all nodes.
The bucket contains block headers keyed by the block height encoded as
big-endian concatenated with the block hash. This allows block headers
to be fetched from the DB in height order with a cursor.
These method allows safe concurrent access to reading and modifying
block node statuses. When block statuses get persisted in a later
change, the setter methods can be used to mark block nodes as dirty.
Each node in the block index records some flags about its validation
state. This is just stored in memory for now, but can save effort if
attempting to reconnect a block that failed validation or was
disconnected.
This was only used to test block proposals, which has been changed to
instead use CheckConnectBlockTemplate. The flag complicated the
implementation of some chain processing routines and would be
difficult to implement with headers-first syncing.
This renames CheckConnectBlock to CheckConnectBlockTemplate and
modifies it to be easily consumable by the getblocktemplate RPC
handler. Performs full block validation now instead of partial
validation.
This propagates the interrupt channel through to blockchain and the
indexers so that it is possible to interrupt long-running operations
such as catching up indexes.
This refactors the code that locates blocks (inventory discovery) out of
server and into blockchain where it can make use of the new much more
efficient chain view and more easily be tested. As an aside, it really
belongs in blockchain anyways since it's purely dealing with the block
index and best chain.
Since the majority of the network has moved to header-based semantics,
this also provides an additional optimization to allow headers to be
located directly versus needing to first discover the hashes and then
fetch the headers.
The new functions are named LocateBlocks and LocateHeaders. The former
returns a slice of located hashes and the latter returns a slice of
located headers.
Finally, it also updates the RPC server getheaders call and related
plumbing to use the new LocateHeaders function.
A comprehensive suite of tests is provided to ensure both functions
behave correctly for both correct and incorrect block locators.
- Remove inMainChain from block nodes since that can now be efficiently
determined by using the chain view
- Track the best chain via a chain view instead of a single block node
- Use the tip of the best chain view everywhere bestNode was used
- Update chain view tip instead of updating best node
- Change reorg logic to use more efficient chain view fork finding logic
- Change block locator code over to use more efficient chain view logic
- Remove now unused block-index-based block locator code
- Move BlockLocator definition to chain.go
- Move BlockLocatorFromHash and LatestBlockLocator to chain.go
- Update both to use more efficient chain view logic
- Rework IsCheckpointCandidate to use block index and chain view
- Optimize MainChainHasBlock to use chain view instead of hitting db
- Move to chain.go since it no longer involves database I/O
- Removed error return since it can no longer fail
- Optimize BlockHeightByHash to use chain view instead of hitting db
- Move to chain.go since it no longer involves database I/O
- Removed error return since it can no longer fail
- Optimize BlockHashByHeight to use chain view instead of hitting db
- Move to chain.go since it no longer involves database I/O
- Removed error return since it can no longer fail
- Optimize HeightRange to use chain view instead of hitting db
- Move to chain.go since it no longer involves database I/O
- Optimize BlockByHeight to use chain view for main chain check
- Optimize BlockByHash to use chain view for main chain check
This removes the DisableVerify function and related state since nothing
uses it anymore since the command line option was removed. It is a
remnant of initial development.
This exposes the ability to more efficiently create a block locator from
a chain view for a given block node by using their ability to do O(1)
lookups.
It also adds tests to ensure the behavior is correct.
This significantly optimizes and simplifies the generation of block
locators by making use of the fact that all block nodes are now in
memory and therefore it is no longer necessary to consult the database
for the hashes or worry about issues related to dynamic loading of nodes.
Also, it slightly modifies the algorithm so that the doubling doesn't
start for one additional iteration in order to mirror other prominent
clients on the network. Due to the way block locators are used, this
does not change any semantics in terms of requesting and locating
blocks.
Finally, the semantics of BlockLocatorFromHash have been changed to
return a locator for the current tip in the case the hash is unknown.
This is far preferable since only including the passed block hash, when
it isn't known, could end up leading to causing a redownload of the
entire chain under certain circumstances.
