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* Explicitly use shared `Kvt` table on `Ledger` and `Clique` lookup. why: Speeds up lookup time with `Aristo` backend. For writing `Clique` data, the `Companion` model allows to write `Clique` data past the database locked by evm transactions. * Implement `CoreDb` profiling with API tracking why: Chasing time spent per APT procs ... * Implement `Ledger` profiling with API tracking why: Chasing time spent per APT procs ... * Always hashify when commiting or storing why: A dirty cache makes no sense when committing * Make sure that a zero key is created when adding/updating vertices why: This is an error fix mainly for edge cases. A typical error was that the root key got deleted when there were only a few vertices left on the DB. * Need all created and changed vertices zero-keyed on the cache why: A zero key (i.e. empty Merkle hash) indicates that a vertex key needs to be updated. This would not be needed immediately after a merge as there is an actual leaf path on the cache layer. But after subsequent merge and delete operations this information might get blurred. * Re-org hashing algorithm why: Apart from errors, the previous implementation was too slow for two reasons: + some control hashes were calculated for debugging (now all verification is done in `aristo_check` module) + the leaf paths stored on the cache are used to build the labelling (aka hashing) schedule; there paths were accumulated over successive hash sessions although it is clear that all keys were generated, already
Core database replacement wrapper object
This wrapper replaces the TrieDatabaseRef and its derivatives by the new object CoreDbRef.
Relations to current TrieDatabaseRef implementation
Here are some incomplete translations for objects and constructors.
Object types:
Legacy notation | CoreDbRef based replacement |
---|---|
ChainDB | (don't use/avoid) |
ChainDbRef | CoreDbRef |
TrieDatabaseRef | CoreDbKvtRef |
HexaryTrie | CoreDbMptRef |
SecureHexaryTrie | CoreDbPhkRef |
DbTransaction | CoreDbTxRef |
TransactionID | CoreDbTxID |
Constructors:
Legacy notation | CoreDbRef based replacement |
---|---|
trieDB newChainDB("..") | newCoreDbRef(LegacyDbPersistent,"..") |
newMemoryDB() | newCoreDbRef(LegacyDbMemory) |
-- | |
initHexaryTrie(db,..) | db.mpt(..) (no pruning) |
db.mptPrune(..) (w/pruning true/false) | |
-- | |
initSecureHexaryTrie(db,..) | db.phk(..) (no pruning) |
db.phkPrune(..) (w/pruning true/false) | |
-- | |
newCaptureDB(db,memDB) | db.capture() (see below) |
Usage of the replacement wrapper
Objects pedigree:
CoreDbRef -- base descriptor
| | | |
| | | +-- CoreDbMptRef -- hexary trie instance
| | | | : :
| | | +-- CoreDbMptRef -- hexary trie instance
| | |
| | |
| | +---- CoreDbPhkRef -- pre-hashed key hexary trie instance
| | | : :
| | +---- CoreDbPhkRef -- pre-hashed key hexary trie instance
| |
| |
| +------ CoreDbKvtRef -- single static key-value table
|
|
+-------- CoreDbCaptRef -- tracer support descriptor
Instantiating standard database object descriptors works as follows:
let
db = newCoreDbRef(..) # new base descriptor
mpt = db.mpt(..) # hexary trie/Merkle Patricia Tree
phk = db.phk(..) # pre-hashed key hexary trie/MPT
kvt = db.kvt # key-value table
Tracer support setup by hiding the current CoreDbRef behind a replacement:
let
capture = db.capture()
db = capture.recorder # use the recorder in place of db
...
for key,value in capture.recorder.kvt:
... # process recorded data