* 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
* 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.)