The order in which storage.Find items are returns depends on what items
were processed in previous transactions of the same block.
The easiest way to implement this sort of caching is to cache operations
with storage, flushing the only in `Persist()`.
This syscall should only work for contracts created by current transaction and
that is what is supposed to be checked here. Do so by looking at the
differences between ic.dao and original lower DAO.
Our block.Block was JSONized in a bit different fashion than result.Block in
its Nonce and NextConsensus fields. It's not good for notifications because
third-party clients would probably expect to see the same format. Also, using
completely different Block representation in result is probably making our
client a bit weaker as this representation is harder to use with other neo-go
components.
So use the same approach we took for Transactions and wrap block.Base which is
to be serialized in proper way.
Getting batch, updating Prometheus metrics and pushing events doesn't require
any locking: batch is a local cache batch that no one outside cares about,
Prometheus metrics are not critical to be in perfect sync and events are
asynchronous anyway.
Which makes iterating over map stable which is important for serialization and
and even fixes occasional test failures. We use the same ordering here as
NEO 3.0 uses, but it should also be fine for NEO 2.0 because it has no
defined order.
Most of the time it's persisted into the MemoryStore or MemCachedStore, when
that's the case there is no real need to go through the Batch mechanism as it
incurs multiple copies of the data.
Importing 1.5M mainnet blocks with verification turned off, before:
real 12m39,484s
user 20m48,300s
sys 2m25,022s
After:
real 11m15,053s
user 18m2,755s
sys 2m4,162s
So it's around 10% improvement which looks good enough.
Frequently one needs to check if struct serializes/deserializes
properly. This commit implements helpers for such cases including:
1. JSON
2. io.Serializable interface
When serializing multiple accounts, cost of a buffer grow
can become significant. This commit tries to amortize it by
reusing the same buffer in a single `Persist()` call.
Fixes difference in state changes at mainnet's block 2442790 because contract
migration in b4eb2dc35226e6520ee4e09a56197dff91547b50a7f57edc82930fc18c75dffc
doesn't actually transfer the storage state, it only deletes the old one.
And add an error check just in case.
