* Relocated mothballing (i.e. swap-in preparation) logic
details:
Mothballing was previously tested & started after downloading
account ranges in `range_fetch_accounts`.
Whenever current download or healing stops because of a pivot change,
swap-in preparation is needed (otherwise some storage slots may get
lost when swap-in takes place.)
Also, `execSnapSyncAction()` has been moved back to `pivot_helper`.
* Reorganised source file directories
details:
Grouped pivot focused modules into `pivot` directory
* Renamed `checkNodes`, `sickSubTries` as `nodes.check`, `nodes.missing`
why:
Both lists are typically used together as pair. Renaming `sickSubTries`
reflects moving away from a healing centric view towards a swap-in
attitude.
* Multi times coverage recording
details:
Per pivot account ranges are accumulated into coverage range set. This
set fill eventually contain a singe range of account hashes [0..2^256]
which amounts to 100% capacity.
A counter has been added that is incremented whenever max capacity is
reached. The accumulated range is then reset to empty.
The effect of this setting is that the coverage can be evenly duplicated.
So 200% would not accumulate on a particular region.
* Update range length comparisons (mod 2^256)
why:
A range interval can have sizes 1..2^256 as it cannot be empty by
definition. The number of points in a range intervals set can have
0..2^256 points. As the scalar range is a residue class modulo 2^256,
the residue class 0 means length 2^256 for a range interval, but can
be 0 or 2^256 for the number of points in a range intervals set.
* Generalised `hexaryEnvelopeDecompose()`
details:
Compile the complement of the union of some (processed) intervals and
express this complement as a list of envelopes of sub-tries.
This facility is directly applicable to swap-in book-keeping.
* Re-factor `swapIn()`
why:
Good idea but baloney implementation. The main algorithm is based on
the generalised version of `hexaryEnvelopeDecompose()` which has been
derived from this implementation.
* Refactor `healAccounts()` using `hexaryEnvelopeDecompose()` as main driver
why:
Previously, the hexary trie was searched recursively for dangling nodes
which has a poor worst case performance already when the trie is
reasonably populated.
The function `hexaryEnvelopeDecompose()` is a magnitude faster because
it does not peruse existing sub-tries in order to find missing nodes
although result is not fully compatible with the previous function.
So recursive search is used in a limited mode only when the decomposer
will not deliver a useful result.
* Logging & maintenance fixes
details:
Preparation for abandoning buddy-global healing variables `node`,
`resumeCtx`, and `lockTriePerusal`. These variable are trie-perusal
centric which will be run on the back burner in favour of
`hexaryEnvelopeDecompose()` which is used for accounts healing already.
* Miscellaneous updates TBC
* Disentangled pivot2 module from snap
why:
Wrote as template on top of sync so it can be shared by fast and snap
sync.
* Renamed and relocated pivot sources
* Integrated `best_pivot` module into full and snap sync
why:
Full sync used an older version of `best_pivot`
* isolating download module from full sync
why;
might be shared with snap sync at a later stage
* Re-implemented `hexaryFollow()` in a more general fashion
details:
+ New name for re-implemented `hexaryFollow()` is `hexaryPath()`
+ Renamed `rTreeFollow()` as `hexaryPath()`
why:
Returning similarly organised structures, the results of the
`hexaryPath()` functions become comparable when running over
the persistent and the in-memory databases.
* Added traversal functionality for persistent ChainDB
* Using `Account` values as re-packed Blob
* Repack samples as compressed data files
* Produce test data
details:
+ Can force pivot state root switch after minimal coverage.
+ For emulating certain network behaviour, downloading accounts stops for
a particular pivot state root if 30% (some static number) coverage is
reached. Following accounts are downloaded for a later pivot state root.
* Provided common scheduler API, applied to `full` sync
* Use hexary trie as storage for proofs_db records
also:
+ Store metadata with account for keeping track of account state
+ add iterator over accounts
* Common scheduler API applied to `snap` sync
* Prepare for accounts bulk import
details:
+ Added some ad-hoc checks for proving accounts data received from the
snap/1 (will be replaced by proper database version when ready)
+ Added code that dumps some of the received snap/1 data into a file
(turned of by default, see `worker_desc.nim`)
