GAS can only be distributed once in a block for particular address, so it
makes little sense trying to calculate it again and again. This fixes
neo-bench for NEO voter, because without it we get ~2500 TPS for
single-address test and with it it jumps 13-fold to normal values like
~33500.
We need to store NEO balance's LastUpdateHeight before GAS mint,
because mint can call onNEP17Payment and onNEP17Payment can call NEO
transfer which also calls GAS mint. Storing balance height allows to
avoid recursion.
We burn GAS in OnPersist for every transaction so some buffer reuse here is
quite natural.
This also doesn't change a lot in the overall TPS picture, maybe adding some
1%.
Which duplicates the check, but deduplicates error path. This check forced
double balance deserialization which is quite costly operation, so we better
do it once.
It's hardly noticeable as of TPS metrics though, maybe some 1-2%%.
Request NEP17 balances from a set of NEP17 contracts instead of getting
them from storage. LastUpdatedBlock tracking remains untouched, because
there's no way to retrieve it dynamically.
We have a lot of native contract types that are converted to stack items
before serialization, then deserialized as stack items and converted back to
regular structures. stackitem.Convertible allows to remove a lot of repetitive
io.Serializable code.
This also introduces to/from converter in testserdes which unfortunately
required to change util tests to avoid circular references.
`storage.Seek()` is rather expensive and we need only last updated value
of gas per block in `PostPersist()`.
Signed-off-by: Evgeniy Stratonikov <evgeniy@nspcc.ru>
(*NEO).GetCandidates along with getCandidatesCall use candidates sorted
by serialized ECPoint bytes.
(*NEO).computeCommitteeMembers use candidates sorted by votes, and then
by deserialized ECPoint, i.e. using default ECPoint comparator.
Not from DAO's items with storage.STNEP17Balances prefix, because
changes are reflected there only after notifications processing. And
this happens only after the transaction script is executed, but there
might be cases when we need to get the balance that was updated
earlier during the same transaction processing.
Affects storage dumps.
After getting account from the storage there are a lot of checks which
may fail. But C# node uses Snapshot.GetAndChange, so the account state
should be put in the storage even in case of vote failure. Affects
dumps.
C# node returns an error if the candidate is not registered. We have this
check inside the ModifyAccountVotes, but (*NEO).vote doesn't panics and
just return bool on stack, so we should match exactly the C#'s
algorithm.
1. `System.Contract.CallNative` expects version on stack.
2. Actual method is determined based on current
instruction pointer.
3. Native hashes don't longer depend on NEF checksum.
But don't change the way we process/store transactions and blocks. Effectively
it's just an interface for smart contracts that replaces old syscalls.
Transaction definition is moved temporarily to runtime package and Block
definition is removed (till we solve #1691 properly).
In (*NEO).computeCommitteeMembers we return standbyCommittee in case
if there's not enought candidates. But there can be standby committee
members among candidates, so we need to fill in known votes.