* Aristo: Merge `delta_siblings` module into `deltaPersistent()`
* Aristo: Add `isEmpty()` for canonical checking whether a layer is empty
* Aristo: Merge `LayerDeltaRef` into `LayerObj`
why:
No need to maintain nested object refs anymore. Previously the
`LayerDeltaRef` object had a companion `LayerFinalRef` which held
non-delta layer information.
* Kvt: Merge `LayerDeltaRef` into `LayerRef`
why:
No need to maintain nested object refs (as with `Aristo`)
* Kvt: Re-write balancer logic similar to `Aristo`
why:
Although `Kvt` was a cheap copy of `Aristo` it sort of got out of
sync and the balancer code was wrong.
* Update iterator over forked peers
why:
Yield additional field `isLast` indicating that the last iteration
cycle was approached.
* Optimise balancer calculation.
why:
One can often avoid providing a new object containing the merge of two
layers for the balancer. This avoids copying tables. In some cases this
is replaced by `hasKey()` look ups though. One uses one of the two
to combine and merges the other into the first.
Of course, this needs some checks for making sure that none of the
components to merge is eventually shared with something else.
* Fix copyright year
* 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`.
* CoreDb: Merged all sub-descriptors into `base_desc` module
* Dissolve `aristo_db/common_desc.nim`
* No need to export `Aristo` methods in `CoreDb`
* Resolve/tighten methods in `aristo_db` sub-moduled
why:
So they can be straihgt implemented into the `base` module
* Moved/re-implemented `KVT` methods into `base` module
* Moved/re-implemented `MPT` methods into `base` module
* Moved/re-implemented account methods into `base` module
* Moved/re-implemented `CTX` methods into `base` module
* Moved/re-implemented `handler_{aristo,kvt}` into `aristo_db` module
* Moved/re-implemented `TX` methods into `base` module
* Moved/re-implemented base methods into `base` module
* Replaced `toAristoSavedStateBlockNumber()` by proper base method
why:
Was the last for keeping reason for keeping low level backend access
methods
* Remove dedicated low level access to `Aristo` backend
why:
Not needed anymore, for debugging the descriptors can be accessed
directly
also:
some clean up stuff
* Re-factor `CoreDb` descriptor layout and adjust base methods
* Moved/re-implemented iterators into `base_iterator*` modules
* Update docu
* 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
It is common for many accounts to share the same code - at the database
level, code is stored by hash meaning only one copy exists per unique
program but when loaded in memory, a copy is made for each account.
Further, every time we execute the code, it must be scanned for invalid
jump destinations which slows down EVM exeuction.
Finally, the extcodesize call causes code to be loaded even if only the
size is needed.
This PR improves on all these points by introducing a shared
CodeBytesRef type whose code section is immutable and that can be shared
between accounts. Further, a dedicated `len` API call is added so that
the EXTCODESIZE opcode can operate without polluting the GC and code
cache, for cases where only the size is requested - rocksdb will in this
case cache the code itself in the row cache meaning that lookup of the
code itself remains fast when length is asked for first.
With 16k code entries, there's a 90% hit rate which goes up to 99%
during the 2.3M attack - the cache significantly lowers memory
consumption and execution time not only during this event but across the
board.
For the block cache to be shared between column families, the options
instance must be shared between the various column families being
created. This also ensures that there is only one source of truth for
configuration options instead of having two different sets depending on
how the tables were initialized.
This PR also removes the re-opening mechanism which can double startup
time - every time the database is opened, the log is replayed - a large
log file will take a long time to open.
Finally, several options got correclty implemented as column family
options, including an one that puts a hash index in the SST files.
* Fix initialiser
why:
Possible crash (app profiling, tracer etc.)
* Update column family options processing
why:
Same for kvt as for aristo
* Move `AristoDbDualRocks` backend type to the test suite
why:
So it is not available for production
* Fix typos in API jump table
why:
Used for tracing and app profiling only. Needed some update
* Purged CoreDb legacy API
why:
Not needed anymore, was transitionary and disabled.
* Rename `flush` argument to `eradicate` in a DB close context
why:
The word `eradicate` leaves no doubt what is meant
* Rename `stoFlush()` -> `stoDelete()`
* Rename `core_apps_newapi` -> `core_apps` (not so new anymore)
* bump rockdb
* Rename `KVT` objects related to filters according to `Aristo` naming
details:
filter* => delta*
roFilter => balancer
* Compulsory error handling if `persistent()` fails
* Add return code to `reCentre()`
why:
Might eventually fail if re-centring is blocked. Some logic will be
added in subsequent patch sets.
* Add column families from earlier session to rocksdb in opening procedure
why:
All previously used CFs must be declared when re-opening an existing
database.
* Update `init()` and add rocksdb `reinit()` methods for changing parameters
why:
Opening a set column families (with different open options) must span
at least the ones that are already on disk.
* Provide write-trigger-event interface into `Aristo` backend
why:
This allows to save data from a guest application (think `KVT`) to
get synced with the write cycle so the guest and `Aristo` save all
atomically.
* Use `KVT` with new column family interface from `Aristo`
* Remove obsolete guest interface
* Implement `KVT` piggyback on `Aristo` backend
* CoreDb: Add separate `KVT`/`Aristo` backend mode for debugging
* Remove `rocks_db` import from `persist()` function
why:
Some systems (i.p `fluffy` and friends) use the `Aristo` memory
backend emulation and do not link against rocksdb when building the
application. So this should fix that problem.
The `rocksdb` version shipped with distributions is typically old and
therefore often lacks features we use - it also doesn't match the one
assumed by nim-rocksdb leading to ABI mismatch risks.
Instead of depending on the system rocksdb, we'll now use the rocksdb
version assumed by nim-rocksdb and locked in its vendor folder by always
building it together with nimbus.
This avoids the problem of unknown rocksdb versions at a (small) cost to
build time.
CI caching and full windows support for building from source [remains
TODO](https://github.com/status-im/nim-rocksdb/issues/44).
* Remove all journal related stuff
* Refactor function names journal*() => delta*(), filter*() => delta*()
* remove `trg` fileld from `FilterRef`
why:
Same as `kMap[$1]`
* Re-type FilterRef.src as `HashKey`
why:
So it is directly comparable to `kMap[$1]`
* Moved `vGen[]` field from `LayerFinalRef` to `LayerDeltaRef`
why:
Then a separate `FilterRef` type is not needed, anymore
* Rename `roFilter` field in `AristoDbRef` => `balancer`
why:
New name more appropriate.
* Replace `FilterRef` by `LayerDeltaRef` type
why:
This allows to avoid copying into the `balancer` (see next patch set)
most of the time. Typically, only one instance is running on the backend
and the `balancer` is only used as a stage before saving data.
* Refactor way how to store data persistently
why:
Avoid useless copy when staging `top` layer for persistently saving to
backend.
* Fix copyright header?
* Aristo: Generalise alien/guest interface for piggiback on database
* Aristo: Code cosmetics
* CoreDb+Kvt: Update transaction API
why:
Use single addressable function `forkTx(backLevel: int)` as used
in `Aristo`. So `Kvt` can be synced simultaneously to `Aristo`.
also:
Refactored `kvt_tx.nim` in a similar fashion to `Aristo`.
* Kvt: Replace `LayerDelta` object by reference
why:
Will be needed when introducing filters
* Kvt: Remodel backend filter facility similar to `Aristo`
why:
This allows to operate on several KVT instances simultaneously.
* CoreDb+Kvt: Fix on-disk storage
why:
Overlooked name change: `stow()` => `persist()` for permanent storage
* Fix copyright headers
* Aristo+Kvt: Better RocksDB profiling
why:
Providing more detailed information, mainly for `Aristo`
* Aristo: Renamed journal `stats()` to `capacity()`
why:
`Stats()` was a misnomer
* Aristo: Provide backend read caches for key and vertex IDs
why:
Dedicated LRU caching for particular types gives a throughput advantage.
The sizes of the LRU queues used for caching are currently constant
but might be adjusted at a later time.
* Fix copyright year
* Code cosmetics
* Aristo+Kvt: Fix api wrappers
why:
Api setup killed the backend descriptor when backend mapping was
disabled.
* Aristo: Implement masked profiling entries
why:
Database backend should be listed but not counted in tally
* CoreDb: Simplify backend() methods
why:
DBMS backend access Was provided very early and over engineered. Now
there are only two backend machines, one for `Kvt` and the other one
for an `Mpt` available only via new API.
* CoreDb: Code cleanup regarding descriptor types
* CoreDb: Refactor/redefine `persistent()` methods
why:
There were `persistent()` methods for any type of caching storage
facilities `Kvt`, `Mpt`, `Phk`, and `Acc`. Now there is only a single
`persistent()` method storing all facilities in tandem (similar to
how transactions work.)
For non shared `Kvt` tables, there is now an extra storage method
`saveOffSite()`.
* CoreDb lingo update: `trie` becomes `column`
why:
Notion of a `trie` is pretty much hidden by the new `CoreDb` api.
Revealed are sort of database columns for accounts an storage data,
any of which have an internal state represented by a Keccack hash.
So a `trie` or `MPT` becomes a `column` and a `rootHash` becomes a
column state.
* Aristo: rename backend filed `filters` => `journal`
* Update full sync logging
details:
+ Disable eth handler noise while syncing
+ Log journal depth (if available)
* Fix copyright year
* Fix cruft and unwanted imports
* Update README
* Nimbus-main: replaced `PruneMode` options by `ChainDbMode` options
details:
For the legacy database, this changes the phrase
- `conf.pruneMode == PruneMode.Full` to the expression
+ `conf.chainDbMode == ChainDbMode.Prune`.
* Fix issues moaned about by NIM compiler
* Fix copyright year
* Aristo+RocksDB: Update backend drivers
why:
RocksDB update allows use some of the newly provided methods which
were previously implemented by using the very C backend (for the lack
of NIM methods.)
* Aristo+RocksDB: Simplify drivers wrapper
* Kvt: Update backend drivers and wrappers similar to `Aristo`
* Aristo+Kvm: Use column families for RocksDB
* Aristo+MemoryDB: Code cosmetics
* Aristo: Provide guest column family for export
why:
So `Kvt` can piggyback on `Aristo` so there avoiding to run a second
DBMS system in parallel.
* Kvt: Provide import mechanism for RoksDB guest column family
why:
So `Kvt` can piggyback on `Aristo` so there avoiding to run a second
DBMS system in parallel.
* CoreDb+Aristo: Run persistent `Kvt` DB piggybacked on `Aristo`
why:
Avoiding to run two DBMS systems in parallel.
* Fix copyright year
* Ditto
* Kvt: Update API hooks
* Aristo: Generalised merging snap proofs, now for multiple state roots
why:
This accommodates pre-loading partial tries for unit tests
* Aristo: Update some unit tests
* CoreDb+Aristo: Re-factor tracer
why:
Was bonkers anyway. The main change is that the trace journal is now
kept in a way similar to a transaction layer so that it can predictably
interact with DB transactions.
* Ledger: Debugging helper
* Update tracer unit test applicable for `Aristo`
* Fix copyright year
* Disable `dump()` function as compile time default
why:
This needs to pull in the `rocks_db` library at compile time.
* CoreDb+Aristo: Fix handler code
* Aristo+Kvt: Remove cruft
* Aristo+Kvt: The function `forkTop()` always provides a single transaction
why:
Previously it provided a single squashed tx only if there were any. Now
it will provide a blind one if there were none.
* Fix Copyright header
why:
Ignoring `nil` objects was handy for a while but eventually led to
lazy programming which in turn led to double destructor calls for
the rocks-db.
* Aristo+Kvt: Fix backend `dup()` function in api setup
why:
Backend object is subject to an inheritance cascade which was not
taken care of, before. Only the base object was duplicated.
* Kvt: Simplify DB clone/peers management
* Aristo: Simplify DB clone/peers management
* Aristo: Adjust unit test for working with memory DB only
why:
This currently causes some memory corruption persumably in the
`libc` background layer.
* CoredDb+Kvt: Simplify API for KVT
why:
Simplified storage models (was over engineered) for better performance
and code maintenance.
* CoredDb+Aristo: Simplify API for `Aristo`
why:
Only single database state needed here. Accessing a similar state will
be implemented from outside this module using a context layer. This
gives better performance and improves code maintenance.
* Fix Copyright headers
* CoreDb: Turn off API tracking
why:
CI would ot go through. Was accidentally turned on.
* Add new RocksNamespaceRef type and remove backups and readonly support from RocksDb KvStore.
* Bump nim-rocksdb to fc2ba4a836b6b47ae1b17d1c45801c7e06585e19
* Fix tests.
* Fix copyright notice.
* Aristo: Remove cruft
* Prettifying profile statistics printing & source code cosmetics
* Aristo/Kvt: API tools update
* CoreDb: Corrections, mostly API related
* CoreDb: Changed the tracer `logDb()` result
why:
Only the key-value table is used from the logger database
* CoreDb: Update legacy tracer
why:
The `contains()` directive did not correspond to `0 < get().len`
also:
Copy `CoreDb` meta settings like `trackLegaApi`, `trackNewApi`, etc. to
overlay tracer descriptor
* CoreDb: Extend/update tracer API
why:
Get ready for accommodating `Aristo` tracer
* Fix missing import
why:
Some CI compilers might have (cached?) a different NIM patch level
* Ditto
* Aristo/Kvt: Provide function hooks APIs
why:
These APIs can be used for installing tracers, profiling functoinality,
and other niceties on the databases.
* Aristo: Provide optional API profiling
details:
It basically is a re-implementation of the `CoreDb` profiling
implementation
* Kvt: Provide optional API profiling similar to `Aristo`
* CoreDb: Re-implementing profiling using `aristo_profile`
* Ledger: Re-implementing profiling using `aristo_profile`
* CoreDb: Update unit tests for maintainability
* update copyright dates
* Aristo: Update unit test suite
* Aristo/Kvt: Fix iterators
why:
Generic iterators were not properly updated after backend change
* Aristo: Add sub-trie deletion functionality
why:
For storage tries linked to an account payload vertex ID, a the
whole storage trie needs to be deleted with the account.
* Aristo: Reserve vertex ID numbers for static custom state roots
why:
Static custom state roots may be controlled by an application,
e.g. for a receipt or a transaction root. The `Aristo` functions
are agnostic of what the static state roots are when different
from the internal tree vertex ID 1.
details;
The `merge()` function applied to a non-static state root (assumed
to be a storage root) will check the payload of an accounts leaf
and mark its Merkle keys to be re-checked.
* Aristo: Correct error code symbol
* Aristo: Update error code symbols
* Aristo: Code cosmetics/comments
* Aristo: Fix hashify schedule calculator
why:
Had a tendency to stop early leaving an incomplete job
* Update KVT layers abstraction
details:
modelled after Aristo layers
* Simplified KVT database iterators (removed item counters)
why:
Not needed for production functions
* Simplify KVT merge function `layersCc()`
* Simplified Aristo database iterators (removed item counters)
why:
Not needed for production functions
* 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.
* Update merging layers and label update functions
why:
+ Merging a stack of layers with `layersCc()` could be simplified
+ Merging layers will optimise the reverse `kMap[]` table maps
`pAmk: label->{vid, ..}` by deleting empty mappings `label->{}` where
they are redundant.
+ Updated `layersPutLabel()` for optimising `pAmk[]` tables
* Fix kvt headers
* Provide differential layers for KVT transaction stack
why:
Significant performance improvement
* Provide abstraction layer for database top cache layer
why:
This will eventually implemented as a differential database layers
or transaction layers. The latter is needed to improve performance.
behavioural changes:
Zero vertex and keys (i.e. delete requests) are not optimised out
until the last layer is written to the database.
* Provide differential layers for Aristo transaction stack
why:
Significant performance improvement
* Fix copyright year
* Show elapsed times with enabled `CoreDb` API tracking
* Show elapsed times with enabled `LedgerRef` API tracking
* Reorg `CoreDb` auto destructors for `Aristo` DB
why:
While `Aristo` supports some parallelism for concurrent database access,
this comes with a price of management overhead. With a naive approach,
the auto-destructor will slow down execution because the ledger and
evm treat the database in a shared mode where a DB descriptor is just
created and thrown away shortly after.
This is reflected in the `Coredb` abstraction layer above `Aristo`/`Kvt`
where a few `Shared` type descriptors are cached and a shared reference
is returned rather than a disposable new object.
* For `CoreDb` support transaction level tracking
details:
This is mainly an extra for the legacy DB as `Aristo` and `Kvt` support
this already.
Also return an error on the legacy DB backend when `persistent()` is
called while there are transactions pending (the `persistent()` call
does nothing otherwise on the legacy backend.)
* Clear compiler warnings (remove unused variables etc.)
* Using different `tmp` directories for `Kvt` and `Aristo`
why:
Closing one database would leave the other set of directories
incomplete.
* Code cosmetics, silence compiler
* Fix typo `EMPTY_ROOT_HASH` vs. `EMPTY_CODE_HASH`
* Fix copyright years
* Disable `TransactionID` related functions from `state_db.nim`
why:
Functions `getCommittedStorage()` and `updateOriginalRoot()` from
the `state_db` module are nowhere used. The emulation of a legacy
`TransactionID` type functionality is administratively expensive to
provide by `Aristo` (the legacy DB version is only partially
implemented, anyway).
As there is no other place where `TransactionID`s are used, they will
not be provided by the `Aristo` variant of the `CoreDb`. For the
legacy DB API, nothing will change.
* Fix copyright headers in source code
* Get rid of compiler warning
* Update Aristo code, remove unused `merge()` variant, export `hashify()`
why:
Adapt to upcoming `CoreDb` wrapper
* Remove synced tx feature from `Aristo`
why:
+ This feature allowed to synchronise transaction methods like begin,
commit, and rollback for a group of descriptors.
+ The feature is over engineered and not needed for `CoreDb`, neither
is it complete (some convergence features missing.)
* Add debugging helpers to `Kvt`
also:
Update database iterator, add count variable yield argument similar
to `Aristo`.
* Provide optional destructors for `CoreDb` API
why;
For the upcoming Aristo wrapper, this allows to control when certain
smart destruction and update can take place. The auto destructor works
fine in general when the storage/cache strategy is known and acceptable
when creating descriptors.
* Add update option for `CoreDb` API function `hash()`
why;
The hash function is typically used to get the state root of the MPT.
Due to lazy hashing, this might be not available on the `Aristo` DB.
So the `update` function asks for re-hashing the gurrent state changes
if needed.
* Update API tracking log mode: `info` => `debug
* Use shared `Kvt` descriptor in new Ledger API
why:
No need to create a new descriptor all the time
* Aristo: Single `FetchPathNotFound` error in `fetchXxx()` and `hasPath()`
why:
Missing path hike returns too many detailed reasons why it failed
which becomes cumbersome to handle.
also:
Renamed `contains()` => `hasPath()` which disables the `in` operator on
non-boolean `contains()` functions
* Kvt: Renamed `contains()` => `hasKey()`
why:
which disables the `in` operator on non-boolean `contains()` functions
* Aristo: Generalising `HashID` by variable length `PathID`
why:
There are cases when the `Aristo` database is to be used with
shorter than 64 nibbles keys when handling transactions indexes
with sequence IDs.
caveat:
This patch only works reliable for full length `PathID` values. Tests
for shorter `PathID` values are currently missing.
* Split `core_db/base.nim` into several sources
* Rename `core_db/legacy.nim` => `core_db/legacy_db.nim`
* Update `CoreDb` API, dual methods returning `Result[]` or plain value
detail:
Plain value methods implemet the legacy API, they defect on error results
* Redesign `CoreDB` direct backend access
why:
Made the `backend` directive integral part of the API
* Discontinue providing unused or otherwise available functions
details:
+ setTransactionID() removed, not used and not easily replicable in Aristo
+ maybeGet() removed, available via direct backend access
+ newPhk() removed, never used & was experimental anyway
* Update/reorg backend API
why:
+ Added error print function `$$()`
+ General descriptor completion (and optional validation) via `bless()`
* Update `Aristo`/`Kvt` exception handling
why:
Avoid `CatchableError` exceptions, rather pass them as error code where
appropriate.
* More `CoreDB` compliant `Aristo` and `Kvt` methods
details:
+ Providing functions like `contains()`, `getVtxRc()` (returns `Result[]`).
+ Additional error code: `NotImplemented`
* Rewrite/reorg of Aristo DB constructor
why:
Previously used global object `DefaultQidLayoutRef` as default
initialiser. This object was created at compile time which lead to
non-gc safe functions.
* Update nimbus/db/core_db/legacy_db.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Update nimbus/db/aristo/aristo_transcode.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Update nimbus/db/core_db/legacy_db.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
---------
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Kvt: Implemented multi-descriptor access on the same backend
why:
This behaviour mirrors the one of Aristo and can be used for
simultaneous transactions on Aristo + Kvt
* Kvt: Update database iterators
why:
Forgot to run on the top layer first
* Kvt: Misc fixes
* Aristo, use `openArray[byte]` rather than `Blob` in prototype
* Aristo, by default hashify right after cloning descriptor
why:
Typically, a completed descriptor is expected after cloning. Hashing
can be suppressed by argument flag.
* Aristo provides `replicate()` iterator, similar to legacy `replicate()`
* Aristo API fixes and updates
* CoreDB: Rename `legacy_persistent` => `legacy_rocksdb`
why:
More systematic, will be in line with Aristo DB which might have
more than one persistent backends
* CoreDB: Prettify API sources
why:
Better to read and maintain
details:
Annotating with custom pragmas which cleans up the prototypes
* CoreDB: Update MPT/put() prototype allowing `CatchableError`
why:
Will be needed for Aristo API (legacy is OK with `RlpError`)
* Update docu
* Update Aristo/Kvt constructor prototype
why:
Previous version used an `enum` value to indicate what backend is to
be used. This was replaced by using the backend object type.
* Rewrite `hikeUp()` return code into `Result[Hike,(Hike,AristoError)]`
why:
Better code maintenance. Previously, the `Hike` object was returned. It
had an internal error field so partial success was also available on
a failure. This error field has been removed.
* Use `openArray[byte]` rather than `Blob` in functions prototypes
* Provide synchronised multi instance transactions
why:
The `CoreDB` object was geared towards the legacy DB which used a single
transaction for the key-value backend DB. Different state roots are
provided by the backend database, so all instances work directly on the
same backend.
Aristo db instances have different in-memory mappings (aka different
state roots) and the transactions are on top of there mappings. So each
instance might run different transactions.
Multi instance transactions are a compromise to converge towards the
legacy behaviour. The synchronised transactions span over all instances
available at the time when base transaction was opened. Instances
created later are unaffected.
* Provide key-value pair database iterator
why:
Needed in `CoreDB` for `replicate()` emulation
also:
Some update of internal code
* Extend API (i.e. prototype variants)
why:
Needed for `CoreDB` geared towards the legacy backend which has a more
basic API than Aristo.
why:
Additional tables needed for the `CoreDB` object with separate
key-value table and MPT.
details:
+ Stripped down copy of Aristo DB to have a similar look'n feel. Otherwise
it is just a posh way for accessing `Table` objects or `RocksDB` data.
+ No unit tests yet, will be tested on the go.