The reverse slot hash mechanism causes quite a bit of database traffic
but is broadly not useful except for iterating the storage of an
account, something that a validator never does (it's used by the
tracers).
This flag adds one more thing that is not stored in the database, to be
explored more comprehensively when designing full, validator and archive
modes with different pruning options in the future.
`ldb` says this is 60gb of data (!):
```
ldb --db=. --ignore_unknown_options --column_family=KvtGen approxsize
--hex --from=0x05
--to=0x05ffffffffffffffffffffffffffffffffffffffffffffff
66488353954
```
* Extract `CoreDb` constructor helpers from `base.nim` into separate module
why:
This makes it easier to avoid circular imports.
* Extract `Ledger` constructor helpers from `base.nim` into separate module
why:
Move `accounts_ledger.nim` file to sub-folder `backend`. That way the
layout resembles that of the `core_db`.
* Updates and corrections
* Extract `CoreDb` configuration from `base.nim` into separate module
why:
This makes it easier to avoid circular imports, in particular
when the capture journal (aka tracer) is revived.
* Extract `Ledger` configuration from `base.nim` into separate module
why:
This makes it easier to avoid circular imports (if any.)
also:
Move `accounts_ledger.nim` file to sub-folder `backend`. That way the
layout resembles that of the `core_db`.
* Tighten `CoreDb` API for accounts
why:
Apart from cruft, the way to fetch the accounts state root via a
`CoreDbColRef` record was unnecessarily complicated.
* Extend `CoreDb` API for accounts to cover storage tries
why:
In future, this will make the notion of column objects obsolete. Storage
trees will then be indexed by the account address rather than the vertex
ID equivalent like a `CoreDbColRef`.
* Apply new/extended accounts API to ledger and tests
details:
This makes the `distinct_ledger` module obsolete
* Remove column object constructors
why:
They were needed as an abstraction of MPT sub-trees including storage
trees. Now, storage trees are handled by the account (e.g. via address)
they belong to and all other trees can be identified by a constant well
known vertex ID. So there is no need for column objects anymore.
Still there are some left-over column object methods wnich will be
removed next.
* Remove `serialise()` and `PayloadRef` from default Aristo API
why:
Not needed. `PayloadRef` was used for unstructured/unknown payload
formats (account or blob) and `serialise()` was used for decodng
`PayloadRef`. Now it is known in advance what the payload looks
like.
* Added query function `hasStorageData()` whether a storage area exists
why:
Useful for supporting `slotStateEmpty()` of the `CoreDb` API
* In the `Ledger` replace `storage.stateEmpty()` by `slotStateEmpty()`
* On Aristo, hide the storage root/vertex ID in the `PayloadRef`
why:
The storage vertex ID is fully controlled by Aristo while the
`AristoAccount` object is controlled by the application. With the
storage root part of the `AristoAccount` object, there was a useless
administrative burden to keep that storage root field up to date.
* Remove cruft, update comments etc.
* Update changed MPT access paradigms
why:
Fixes verified proxy tests
* Fluffy cosmetics
* Update some docu & messages
* Remove cruft from the ledger modules
* Must not overwrite genesis data on an initialised database
why:
This will overwrite the global state of the Aristo single state DB.
Otherwise resuming at the last synced state becomes impossible.
* Provide latest block number from journal
why:
This relates the global state of the DB directly to the corresponding
block number.
* Implemented unit test providing DB pre-load and resume
* Aristo: Re-phrase `LayerDelta` and `LayerFinal` as object references
why:
Avoids copying in some cases
* Fix copyright header
* Aristo: Verify `leafTie.root` function argument for `merge()` proc
why:
Zero root will lead to inconsistent DB entry
* Aristo: Update failure condition for hash labels compiler `hashify()`
why:
Node need not be rejected as long as links are on the schedule. In
that case, `redo[]` is to become `wff.base[]` at a later stage.
This amends an earlier fix, part of #1952 by also testing against
the target nodes of the `wff.base[]` sets.
* Aristo: Add storage root glue record to `hashify()` schedule
why:
An account leaf node might refer to a non-resolvable storage root ID.
Storage root node chains will end up at the storage root. So the link
`storage-root->account-leaf` needs an extra item in the schedule.
* Aristo: fix error code returned by `fetchPayload()`
details:
Final error code is implied by the error code form the `hikeUp()`
function.
* CoreDb: Discard `createOk` argument in API `getRoot()` function
why:
Not needed for the legacy DB. For the `Arsto` DB, a lazy approach is
implemented where a stprage root node is created on-the-fly.
* CoreDb: Prevent `$$` logging in some cases
why:
Logging the function `$$` is not useful when it is used for internal
use, i.e. retrieving an an error text for logging.
* CoreDb: Add `tryHashFn()` to API for pretty printing
why:
Pretty printing must not change the hashification status for the
`Aristo` DB. So there is an independent API wrapper for getting the
node hash which never updated the hashes.
* CoreDb: Discard `update` argument in API `hash()` function
why:
When calling the API function `hash()`, the latest state is always
wanted. For a version that uses the current state as-is without checking,
the function `tryHash()` was added to the backend.
* CoreDb: Update opaque vertex ID objects for the `Aristo` backend
why:
For `Aristo`, vID objects encapsulate a numeric `VertexID`
referencing a vertex (rather than a node hash as used on the
legacy backend.) For storage sub-tries, there might be no initial
vertex known when the descriptor is created. So opaque vertex ID
objects are supported without a valid `VertexID` which will be
initalised on-the-fly when the first item is merged.
* CoreDb: Add pretty printer for opaque vertex ID objects
* Cosmetics, printing profiling data
* CoreDb: Fix segfault in `Aristo` backend when creating MPT descriptor
why:
Missing initialisation error
* CoreDb: Allow MPT to inherit shared context on `Aristo` backend
why:
Creates descriptors with different storage roots for the same
shared `Aristo` DB descriptor.
* Cosmetics, update diagnostic message items for `Aristo` backend
* Fix Copyright year
* 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
* Make sure that storage tries are not pruned (by default) on the new Ledger API
why:
Pruning might kill some unwanted entries from storage tries ending up with an unstable database
leading to crashes.
* Implement `CoreDb` and `LedgerRef` API tracing
details:
+ Locally enabled at compile time via constants `ProvideCoreDbLegacyAPI`
and `EnableApiTracking` in either `base.nim` source
+ If enabled it can be selectively turned on/off via public switches in
the `CoreDb` descriptor.
* Allow suppressing opportunistic `ifNecessaryGetXxx()` functions
why:
Better troubleshooting when the system crashes (assertions will then
most probably happen outside an `async` function.)
* Provide TDD/debug facility for inspecting `persistBlocks()` working
detail:
+ Make sure that the last block of a test sample is the first batch
item in `persistBlocks()`.
+ Additionally, allow `AccountsCache` API tracing by setting the flag
`extraTraceMessages = true` in the file `accounts_cache.nim`
* Overload AccountsCache by abstraction wrapper
details:
Can facilitate CoreDb API switch, details in `ledger/README.md`.