The work on this was started last week while I was waiting
for a decision on the "Async Snappy" PR. It was prompted by
a failing test in the test suite, where the HashingStream
was inserting some incorrectly padded chunks that affected
the result of `hash_tree_root`. Instead of working around
the problem in the HashingStream, I've decided to implement
a planned optimisation that allows us to remove the hashing
stream altogether.
With the optimisation in place, `hash_tree_root` will now
use only stack memory and only the precise amount neccesary
to build the chunks-merging tree.
* switch state cache to use ref statedata objects to limit memory usage
* more directly initialize ref StateData
* use HashedBeaconState instead of StateData to try to fix memory leak
* switch cache to seq[ref HashedBeaconState]
* remove unused import
Co-authored-by: Ștefan Talpalaru <stefantalpalaru@yahoo.com>
* sync fixes
* fix Status message finalized info
* work around sync starting before initial status exchange
* don't fail block on deposit signature check failure (fixes#989)
* print ForkDigest and Version nicely
* dump incoming blocks
* fix crash when libp2p peer connection is closed
* update chunk size to 16 to work around missing blocks when syncing
* bump libp2p
* bump libp2p
* better deposit skip message
* fix some warnings related to beacon_node splitting; reimplement finalization verification more robustly; improve attestation pool block selection logic
* re-add missing import
* whitelist allowed state transition flags and make rollback/restore naming more consistent
* restore usage of update flags passed into skipAndUpdateState(...) in addition to the potential verifyFinalization flag
* switch rest of rollback -> restore
When replaying state transitions, for the slots that have a block, the
state root is taken from the block. For slots that lack a block, it's
currently calculated using hash_tree_root which is expensive.
Caching the empty slot state roots helps us avoid recalculating this
hash, meaning that for replay, hashes are never calculated. This turns
blocks into fairly lightweight "state-diffs"!
* avoid re-saving state when replaying blocks
* advance empty slots slot-by-slot and save root
* fix sim randomness
* fix sim genesis filename
* introduce `isEpoch` to check if a slot is an epoch slot
