From 8dd038144b67d05ddcc1ff3c7d0b0b57ab273acb Mon Sep 17 00:00:00 2001
From: Jordan Hrycaj <jordan@status.im>
Date: Fri, 28 Jun 2024 18:43:04 +0000
Subject: [PATCH] Some cleanups (#2428)

* Remove `dirty` set from structural objects

why:
  Not used anymore, the tree is dirty by default.

* Rename `aristo_hashify` -> `aristo_compute`

* Remove cruft, update comments, cosmetics, etc.

* Simplify `SavedState` object

why:
  The key chaining have become obsolete after extra lazy hashing. There
  is some available space for a state hash to be maintained in future.

details:
  Accept the legacy `SavedState` object serialisation format for a
  while (which will be overwritten by new format.)
---
 nimbus/db/aristo/README.md                    |  6 +-
 nimbus/db/aristo/aristo_blobify.nim           | 35 ++++-------
 nimbus/db/aristo/aristo_check.nim             |  8 +--
 nimbus/db/aristo/aristo_check/check_be.nim    |  9 +--
 nimbus/db/aristo/aristo_check/check_top.nim   |  2 +-
 ...{aristo_hashify.nim => aristo_compute.nim} |  3 -
 nimbus/db/aristo/aristo_debug.nim             |  6 --
 nimbus/db/aristo/aristo_delete.nim            |  4 +-
 nimbus/db/aristo/aristo_delta.nim             |  3 +-
 nimbus/db/aristo/aristo_delta/delta_merge.nim | 26 --------
 .../db/aristo/aristo_delta/delta_reverse.nim  |  2 +-
 nimbus/db/aristo/aristo_desc/desc_error.nim   |  8 ---
 .../db/aristo/aristo_desc/desc_structural.nim | 10 +--
 nimbus/db/aristo/aristo_fetch.nim             |  2 +-
 nimbus/db/aristo/aristo_layers.nim            |  8 ---
 nimbus/db/aristo/aristo_merge.nim             |  4 +-
 nimbus/db/aristo/aristo_sign.nim              |  3 +-
 nimbus/db/aristo/aristo_tx/tx_frame.nim       |  2 +-
 nimbus/db/aristo/aristo_tx/tx_stow.nim        |  5 +-
 nimbus/db/aristo/aristo_utils.nim             | 61 +------------------
 nimbus/db/core_db/backend/aristo_db.nim       |  5 +-
 nimbus/db/core_db/core_apps.nim               | 28 +++++----
 tests/test_aristo/test_filter.nim             |  5 +-
 tests/test_aristo/test_tx.nim                 | 12 ----
 tests/test_coredb/coredb_test_xx.nim          |  2 +-
 25 files changed, 55 insertions(+), 204 deletions(-)
 rename nimbus/db/aristo/{aristo_hashify.nim => aristo_compute.nim} (98%)

diff --git a/nimbus/db/aristo/README.md b/nimbus/db/aristo/README.md
index ad47ec9bd..ee20d869a 100644
--- a/nimbus/db/aristo/README.md
+++ b/nimbus/db/aristo/README.md
@@ -358,12 +358,10 @@ assumed, i.e. the list with the single vertex ID *1*.
 ### 4.7 Serialisation of a last saved state record
 
          0 +--+--+--+--+--+ .. --+--+ .. --+
-           |                               | -- 32 bytes source state hash
+           |                               | -- 32 bytes state hash
         32 +--+--+--+--+--+ .. --+--+ .. --+
-           |                               | -- 32 bytes target state hash
-        64 +--+--+--+--+--+ .. --+--+ .. --+
            |                       |         -- state number/block number
-        72 +--+--+--+--+--+--+--+--+
+        40 +--+--+--+--+--+--+--+--+
            |  |                              -- marker(8), 0x7f
            +--+
 
diff --git a/nimbus/db/aristo/aristo_blobify.nim b/nimbus/db/aristo/aristo_blobify.nim
index c86bfbcf1..592c6c334 100644
--- a/nimbus/db/aristo/aristo_blobify.nim
+++ b/nimbus/db/aristo/aristo_blobify.nim
@@ -152,21 +152,7 @@ proc blobify*(tuv: VertexID): Blob =
 
 proc blobifyTo*(lSst: SavedState; data: var Blob): Result[void,AristoError] =
   ## Serialise a last saved state record
-  case lSst.src.len:
-  of 0:
-    data.setLen(32)
-  of 32:
-    data.setLen(0)
-    data.add lSst.src.data
-  else:
-    return err(BlobifyStateSrcLenGarbled)
-  case lSst.trg.len:
-  of 0:
-    data.setLen(64)
-  of 32:
-    data.add lSst.trg.data
-  else:
-    return err(BlobifyStateTrgLenGarbled)
+  data.add lSst.key.data
   data.add lSst.serial.toBytesBE
   data.add @[0x7fu8]
   ok()
@@ -352,17 +338,20 @@ proc deblobifyTo*(
       ): Result[void,AristoError] =
   ## De-serialise the last saved state data record previously encoded with
   ## `blobify()`.
-  if data.len != 73:
+  # Keep that legacy setting for a while
+  if data.len == 73:
+    if data[^1] != 0x7f:
+      return err(DeblobWrongType)
+    lSst.key = EMPTY_ROOT_HASH
+    lSst.serial = uint64.fromBytesBE data.toOpenArray(64, 71)
+    return ok()
+  # -----
+  if data.len != 41:
     return err(DeblobWrongSize)
   if data[^1] != 0x7f:
     return err(DeblobWrongType)
-  func loadHashKey(data: openArray[byte]): Result[HashKey,AristoError] =
-    var w = HashKey.fromBytes(data).valueOr:
-      return err(DeblobHashKeyExpected)
-    ok move(w)
-  lSst.src = ? data.toOpenArray(0, 31).loadHashKey()
-  lSst.trg = ? data.toOpenArray(32, 63).loadHashKey()
-  lSst.serial = uint64.fromBytesBE data.toOpenArray(64, 71)
+  (addr lSst.key.data[0]).copyMem(unsafeAddr data[0], 32)
+  lSst.serial = uint64.fromBytesBE data.toOpenArray(32, 39)
   ok()
 
 proc deblobify*(
diff --git a/nimbus/db/aristo/aristo_check.nim b/nimbus/db/aristo/aristo_check.nim
index e8909f21a..a764a64d4 100644
--- a/nimbus/db/aristo/aristo_check.nim
+++ b/nimbus/db/aristo/aristo_check.nim
@@ -14,7 +14,7 @@
 {.push raises: [].}
 
 import
-  std/[algorithm, sequtils, sets, tables],
+  std/[algorithm, sequtils, tables],
   eth/common,
   stew/interval_set,
   results,
@@ -31,9 +31,9 @@ proc checkTop*(
     proofMode = false;                 # Has proof nodes
       ): Result[void,(VertexID,AristoError)] =
   ## Verify that the cache structure is correct as it would be after `merge()`
-  ## and `hashify()` operations. Unless `proofMode` is set `true` it would not
-  ## fully check against the backend, which is typically not applicable after
-  ## `delete()` operations.
+  ## operations. Unless `proofMode` is set `true` it would not fully check
+  ## against the backend, which is typically not applicable after `delete()`
+  ## operations.
   ##
   ## The following is verified:
   ##
diff --git a/nimbus/db/aristo/aristo_check/check_be.nim b/nimbus/db/aristo/aristo_check/check_be.nim
index aa49d6b13..3d7b7c888 100644
--- a/nimbus/db/aristo/aristo_check/check_be.nim
+++ b/nimbus/db/aristo/aristo_check/check_be.nim
@@ -135,14 +135,7 @@ proc checkBE*[T: RdbBackendRef|MemBackendRef|VoidBackendRef](
   # Check layer cache against backend
   if cache:
     var topVidCache = VertexID(0)
-
-    let checkKeysOk = block:
-      if db.dirty.len == 0:
-        true
-      elif relax:
-        false
-      else:
-        return err((VertexID(0),CheckBeCacheIsDirty))
+    let checkKeysOk = true
 
     # Check structural table
     for (vid,vtx) in db.layersWalkVtx:
diff --git a/nimbus/db/aristo/aristo_check/check_top.nim b/nimbus/db/aristo/aristo_check/check_top.nim
index b8c3c7ed2..e7c7547a3 100644
--- a/nimbus/db/aristo/aristo_check/check_top.nim
+++ b/nimbus/db/aristo/aristo_check/check_top.nim
@@ -42,7 +42,7 @@ proc checkTopStrict*(
       if key != node.digestTo(HashKey):
         return err((vid,CheckStkVtxKeyMismatch))
 
-    elif db.dirty.len == 0 or db.layersGetKey(vid).isErr:
+    elif db.layersGetKey(vid).isErr:
       # So `vtx` exists but not `key`, so cache is supposed dirty and the
       # vertex has a zero entry.
       return err((vid,CheckStkVtxKeyMissing))
diff --git a/nimbus/db/aristo/aristo_hashify.nim b/nimbus/db/aristo/aristo_compute.nim
similarity index 98%
rename from nimbus/db/aristo/aristo_hashify.nim
rename to nimbus/db/aristo/aristo_compute.nim
index ee434e1a9..4960f1bb4 100644
--- a/nimbus/db/aristo/aristo_hashify.nim
+++ b/nimbus/db/aristo/aristo_compute.nim
@@ -11,13 +11,10 @@
 {.push raises: [].}
 
 import
-  chronicles,
   eth/common,
   results,
   "."/[aristo_desc, aristo_get, aristo_layers, aristo_serialise]
 
-logScope:
-  topics = "aristo-hashify"
 
 proc computeKey*(
     db: AristoDbRef;                   # Database, top layer
diff --git a/nimbus/db/aristo/aristo_debug.nim b/nimbus/db/aristo/aristo_debug.nim
index 796064de5..fbe6b3337 100644
--- a/nimbus/db/aristo/aristo_debug.nim
+++ b/nimbus/db/aristo/aristo_debug.nim
@@ -401,7 +401,6 @@ proc ppFilter(
   if fl.isNil:
     result &= " n/a"
     return
-  result &= pfx & "src=" & fl.src.ppKey(db)
   result &= pfx & "vTop=" & fl.vTop.ppVid
   result &= pfx & "sTab" & pfx1 & "{"
   for n,vid in fl.sTab.sortedKeys:
@@ -521,11 +520,6 @@ proc ppLayer(
         tLen = layer.final.fRpp.len
         info = "fRpp(" & $tLen & ")"
       result &= info.doPrefix(0 < tLen) & layer.final.fRpp.ppFRpp(db,indent+2)
-    if 0 < nOKs:
-      let
-        info = if layer.final.dirty.len == 0: "clean"
-               else: "dirty" & layer.final.dirty.ppVids
-      result &= info.doPrefix(false)
 
 # ------------------------------------------------------------------------------
 # Public functions
diff --git a/nimbus/db/aristo/aristo_delete.nim b/nimbus/db/aristo/aristo_delete.nim
index a1e11ef82..90641d5b5 100644
--- a/nimbus/db/aristo/aristo_delete.nim
+++ b/nimbus/db/aristo/aristo_delete.nim
@@ -429,7 +429,7 @@ proc deleteStorageData*(
       return err(DelPathNotFound)
     return err(error[1])
 
-  # Mark account path for update for `hashify()`
+  # Mark account path Merkle keys for update
   db.updateAccountForHasher accHike
 
   db.deleteImpl(stoHike).isOkOr:
@@ -464,7 +464,7 @@ proc deleteStorageTree*(
   if not stoID.isValid:
     return err(DelStoRootMissing)
 
-  # Mark account path for update for `hashify()`
+  # Mark account path Merkle keys for update
   db.updateAccountForHasher accHike
 
   ? db.delSubTreeImpl stoID
diff --git a/nimbus/db/aristo/aristo_delta.nim b/nimbus/db/aristo/aristo_delta.nim
index 0ae96f4ee..764fa363d 100644
--- a/nimbus/db/aristo/aristo_delta.nim
+++ b/nimbus/db/aristo/aristo_delta.nim
@@ -69,8 +69,7 @@ proc deltaPersistent*(
   defer: updateSiblings.rollback()
 
   let lSst = SavedState(
-    src: db.balancer.src,
-    trg: db.balancer.kMap.getOrVoid(VertexID 1),
+    key:  EMPTY_ROOT_HASH,                       # placeholder for more
     serial: nxtFid)
 
   # Store structural single trie entries
diff --git a/nimbus/db/aristo/aristo_delta/delta_merge.nim b/nimbus/db/aristo/aristo_delta/delta_merge.nim
index 29f7487c7..22357caf9 100644
--- a/nimbus/db/aristo/aristo_delta/delta_merge.nim
+++ b/nimbus/db/aristo/aristo_delta/delta_merge.nim
@@ -30,43 +30,22 @@ proc deltaMerge*(
   ## stacked and the database access is `upper -> lower -> backend` whereas
   ## the `src/trg` matching logic goes the other way round.
   ##
-  ## The resuting filter has no `FilterID` set.
-  ##
-  ## Comparing before and after merge
-  ## ::
-  ##   arguments                       | merged result
-  ##   --------------------------------+------------------------------------
-  ##   (src2==trg1) --> upper --> trg2 |
-  ##                                   | (src1==trg0) --> newFilter --> trg2
-  ##   (src1==trg0) --> lower --> trg1 |
-  ##                                   |
-  ##              beStateRoot --> trg0 |
-  ##
   # Degenerate case: `upper` is void
   if lower.isNil:
     if upper.isNil:
       # Even more degenerate case when both filters are void
       return ok LayerDeltaRef(nil)
-    if upper.src != beStateRoot:
-      return err((VertexID(1),FilStateRootMismatch))
     return ok(upper)
 
   # Degenerate case: `upper` is non-trivial and `lower` is void
   if upper.isNil:
-    if lower.src != beStateRoot:
-      return err((VertexID(0), FilStateRootMismatch))
     return ok(lower)
 
   # Verify stackability
   let lowerTrg = lower.kMap.getOrVoid VertexID(1)
-  if upper.src != lowerTrg:
-    return err((VertexID(0), FilTrgSrcMismatch))
-  if lower.src != beStateRoot:
-    return err((VertexID(0), FilStateRootMismatch))
 
   # There is no need to deep copy table vertices as they will not be modified.
   let newFilter = LayerDeltaRef(
-    src:  lower.src,
     sTab: lower.sTab,
     kMap: lower.kMap,
     vTop: upper.vTop)
@@ -95,11 +74,6 @@ proc deltaMerge*(
       else:
         return err((vid,rc.error))
 
-  # # Check consistency
-  # if (newFilter.src == newFilter.kMap.getOrVoid(VertexID 1)) !=
-  #      (newFilter.sTab.len == 0 and newFilter.kMap.len == 0):
-  #   return err((VertexID(0),FilSrcTrgInconsistent))
-
   ok newFilter
 
 # ------------------------------------------------------------------------------
diff --git a/nimbus/db/aristo/aristo_delta/delta_reverse.nim b/nimbus/db/aristo/aristo_delta/delta_reverse.nim
index 0946f42fd..934b0e6d5 100644
--- a/nimbus/db/aristo/aristo_delta/delta_reverse.nim
+++ b/nimbus/db/aristo/aristo_delta/delta_reverse.nim
@@ -29,7 +29,7 @@ proc revFilter*(
   ## backend (excluding optionally installed read-only filter.)
   ##
   # Register MPT state roots for reverting back
-  let rev = LayerDeltaRef(src: filter.kMap.getOrVoid(VertexID 1))
+  let rev = LayerDeltaRef()
 
   # Get vid generator state on backend
   block:
diff --git a/nimbus/db/aristo/aristo_desc/desc_error.nim b/nimbus/db/aristo/aristo_desc/desc_error.nim
index 6a6684122..aeb14329f 100644
--- a/nimbus/db/aristo/aristo_desc/desc_error.nim
+++ b/nimbus/db/aristo/aristo_desc/desc_error.nim
@@ -23,8 +23,6 @@ type
     BlobifyLeafPathOverflow
     BlobifyNilFilter
     BlobifyNilVertex
-    BlobifyStateSrcLenGarbled
-    BlobifyStateTrgLenGarbled
 
 
     # Cache checker `checkCache()`
@@ -157,12 +155,6 @@ type
     GetVtxNotFound
 
 
-    # Update `Merkle` hashes `hashify()`
-    HashifyVtxUnresolved
-    HashifyRootVtxUnresolved
-    HashifyProofHashMismatch
-
-
     # Path function `hikeUp()`
     HikeBranchMissingEdge
     HikeBranchTailEmpty
diff --git a/nimbus/db/aristo/aristo_desc/desc_structural.nim b/nimbus/db/aristo/aristo_desc/desc_structural.nim
index 22c6f1509..6efcd761a 100644
--- a/nimbus/db/aristo/aristo_desc/desc_structural.nim
+++ b/nimbus/db/aristo/aristo_desc/desc_structural.nim
@@ -82,9 +82,8 @@ type
 
   SavedState* = object
     ## Last saved state
-    src*: HashKey                    ## Previous state hash
-    trg*: HashKey                    ## Last state hash
-    serial*: uint64                  ## Generic identifier froom application
+    key*: Hash256                    ## Some state hash (if any)
+    serial*: uint64                  ## Generic identifier from application
 
   LayerDeltaRef* = ref object
     ## Delta layers are stacked implying a tables hierarchy. Table entries on
@@ -109,7 +108,6 @@ type
     ## tables. So a corresponding zero value or missing entry produces an
     ## inconsistent state that must be resolved.
     ##
-    src*: HashKey                    ## Only needed when used as a filter
     sTab*: Table[VertexID,VertexRef] ## Structural vertex table
     kMap*: Table[VertexID,HashKey]   ## Merkle hash key mapping
     vTop*: VertexID                  ## Last used vertex ID
@@ -124,7 +122,6 @@ type
     ##
     pPrf*: HashSet[VertexID]         ## Locked vertices (proof nodes)
     fRpp*: Table[HashKey,VertexID]   ## Key lookup for `pPrf[]` (proof nodes)
-    dirty*: HashSet[VertexID]        ## Start nodes to re-hashiy from
 
   LayerRef* = ref LayerObj
   LayerObj* = object
@@ -276,8 +273,7 @@ func dup*(final: LayerFinalRef): LayerFinalRef =
   ## Duplicate final layer.
   LayerFinalRef(
     pPrf:  final.pPrf,
-    fRpp:  final.fRpp,
-    dirty: final.dirty)
+    fRpp:  final.fRpp)
 
 func dup*(wp: VidVtxPair): VidVtxPair =
   ## Safe copy of `wp` argument
diff --git a/nimbus/db/aristo/aristo_fetch.nim b/nimbus/db/aristo/aristo_fetch.nim
index 0dc10113e..9cfb78eb2 100644
--- a/nimbus/db/aristo/aristo_fetch.nim
+++ b/nimbus/db/aristo/aristo_fetch.nim
@@ -17,7 +17,7 @@ import
   std/typetraits,
   eth/common,
   results,
-  "."/[aristo_desc, aristo_get, aristo_hashify, aristo_hike]
+  "."/[aristo_compute, aristo_desc, aristo_get, aristo_hike]
 
 # ------------------------------------------------------------------------------
 # Private functions
diff --git a/nimbus/db/aristo/aristo_layers.nim b/nimbus/db/aristo/aristo_layers.nim
index d4630c346..9cf3762e9 100644
--- a/nimbus/db/aristo/aristo_layers.nim
+++ b/nimbus/db/aristo/aristo_layers.nim
@@ -29,9 +29,6 @@ func dup(sTab: Table[VertexID,VertexRef]): Table[VertexID,VertexRef] =
 # Public getters: lazy value lookup for read only versions
 # ------------------------------------------------------------------------------
 
-func dirty*(db: AristoDbRef): lent HashSet[VertexID] =
-  db.top.final.dirty
-
 func pPrf*(db: AristoDbRef): lent HashSet[VertexID] =
   db.top.final.pPrf
 
@@ -85,13 +82,10 @@ func layersGetKey*(db: AristoDbRef; vid: VertexID): Opt[HashKey] =
   ## hash key if it is stored on the cache that way.
   ##
   db.top.delta.kMap.withValue(vid, item):
-    # This is ok regardless of the `dirty` flag. If this vertex has become
-    # dirty, there is an empty `kMap[]` entry on this layer.
     return Opt.some(item[])
 
   for w in db.rstack:
     w.delta.kMap.withValue(vid, item):
-      # Same reasoning as above regarding the `dirty` flag.
       return ok(item[])
 
   Opt.none(HashKey)
@@ -126,7 +120,6 @@ func layersPutVtx*(
       ) =
   ## Store a (potentally empty) vertex on the top layer
   db.top.delta.sTab[vid] = vtx
-  # db.top.final.dirty.incl root
 
 func layersResVtx*(
     db: AristoDbRef;
@@ -146,7 +139,6 @@ func layersPutKey*(
       ) =
   ## Store a (potentally void) hash key on the top layer
   db.top.delta.kMap[vid] = key
-  # db.top.final.dirty.incl root # Modified top cache layers => hashify
 
 
 func layersResKey*(db: AristoDbRef; root: VertexID; vid: VertexID) =
diff --git a/nimbus/db/aristo/aristo_merge.nim b/nimbus/db/aristo/aristo_merge.nim
index f2f45453d..94b9fbf88 100644
--- a/nimbus/db/aristo/aristo_merge.nim
+++ b/nimbus/db/aristo/aristo_merge.nim
@@ -126,7 +126,7 @@ proc mergeStorageData*(
     rc = db.mergePayloadImpl(useID, stoPath, pyl)
 
   if rc.isOk:
-    # Mark account path for update for `hashify()`
+    # Mark account path Merkle keys for update
     db.updateAccountForHasher accHike
 
     if stoID.isValid:
@@ -144,7 +144,7 @@ proc mergeStorageData*(
     assert stoID.isValid         # debugging only
     return ok()
 
-  # Error: mark account path for update for `hashify()`
+  # Error: mark account path Merkle keys for update
   db.updateAccountForHasher accHike
   err(rc.error)
 
diff --git a/nimbus/db/aristo/aristo_sign.nim b/nimbus/db/aristo/aristo_sign.nim
index 173ace82c..b139c335f 100644
--- a/nimbus/db/aristo/aristo_sign.nim
+++ b/nimbus/db/aristo/aristo_sign.nim
@@ -16,8 +16,7 @@
 import
   eth/common,
   results,
-  "."/[aristo_constants, aristo_desc, aristo_hashify, aristo_init,
-       aristo_merge]
+  "."/[aristo_compute, aristo_constants, aristo_desc, aristo_init, aristo_merge]
 
 # ------------------------------------------------------------------------------
 # Public functions, signature generator
diff --git a/nimbus/db/aristo/aristo_tx/tx_frame.nim b/nimbus/db/aristo/aristo_tx/tx_frame.nim
index 11fbed1ab..7f9791aaa 100644
--- a/nimbus/db/aristo/aristo_tx/tx_frame.nim
+++ b/nimbus/db/aristo/aristo_tx/tx_frame.nim
@@ -16,7 +16,7 @@
 import
   std/tables,
   results,
-  ".."/[aristo_desc, aristo_layers, aristo_hashify]
+  ".."/[aristo_desc, aristo_layers]
 
 func txFrameIsTop*(tx: AristoTxRef): bool
 
diff --git a/nimbus/db/aristo/aristo_tx/tx_stow.nim b/nimbus/db/aristo/aristo_tx/tx_stow.nim
index 1d5a2ad46..16186bf39 100644
--- a/nimbus/db/aristo/aristo_tx/tx_stow.nim
+++ b/nimbus/db/aristo/aristo_tx/tx_stow.nim
@@ -17,7 +17,7 @@ import
   std/tables,
   results,
   ../aristo_delta/delta_merge,
-  ".."/[aristo_desc, aristo_get, aristo_delta, aristo_layers, aristo_hashify]
+  ".."/[aristo_desc, aristo_get, aristo_delta, aristo_layers]
 
 # ------------------------------------------------------------------------------
 # Private functions
@@ -70,9 +70,6 @@ proc topMerge(db: AristoDbRef; src: HashKey): Result[void,AristoError] =
     else:
       return err(rc.error)
 
-  # Update layer for merge call
-  db.top.delta.src = src
-
   # This one will return the `db.top.delta` if `db.balancer.isNil`
   db.balancer = db.deltaMerge(db.top.delta, db.balancer, ubeRoot).valueOr:
     return err(error[1])
diff --git a/nimbus/db/aristo/aristo_utils.nim b/nimbus/db/aristo/aristo_utils.nim
index 54f44e81e..43a1999fd 100644
--- a/nimbus/db/aristo/aristo_utils.nim
+++ b/nimbus/db/aristo/aristo_utils.nim
@@ -23,58 +23,6 @@ import
 # Public functions, converters
 # ------------------------------------------------------------------------------
 
-proc toAccount*(
-    payload: PayloadRef;
-    db: AristoDbRef;
-      ): Result[Account,AristoError] =
-  ## Converts the argument `payload` to an `Account` type. If the implied
-  ## account das a storage slots system associated, the database `db` must
-  ## contain the Merkle hash key of the root vertex.
-  if payload.pType == AccountData:
-    var acc = Account(
-      nonce:       payload.account.nonce,
-      balance:     payload.account.balance,
-      codeHash:    payload.account.codeHash,
-      storageRoot: EMPTY_ROOT_HASH)
-    if payload.stoID.isValid:
-      acc.storageRoot = (? db.getKeyRc payload.stoID).to(Hash256)
-    return ok(acc)
-
-  err UtilsPayloadTypeUnsupported
-
-proc toAccount*(
-    vtx: VertexRef;
-    db: AristoDbRef;
-      ): Result[Account,AristoError] =
-  ## Variant of `toAccount()` for a `Leaf` vertex.
-  if vtx.isValid and vtx.vType == Leaf:
-    return vtx.lData.toAccount db
-  err UtilsAccVtxUnsupported
-
-proc toAccount*(
-    node: NodeRef;
-      ): Result[Account,AristoError] =
-  ## Variant of `toAccount()` for a `Leaf` node which must be complete (i.e.
-  ## a potential Merkle hash key must have been initialised.)
-  if node.isValid and node.vType == Leaf:
-    if node.lData.pType == AccountData:
-      var acc = Account(
-        nonce:       node.lData.account.nonce,
-        balance:     node.lData.account.balance,
-        codeHash:    node.lData.account.codeHash,
-        storageRoot: EMPTY_ROOT_HASH)
-      if node.lData.stoID.isValid:
-        if not node.key[0].isValid:
-          return err(UtilsAccStorageKeyMissing)
-        acc.storageRoot = node.key[0].to(Hash256)
-      return ok(acc)
-    else:
-      return err(UtilsPayloadTypeUnsupported)
-
-  err UtilsAccNodeUnsupported
-
-# ---------------------
-
 proc toNode*(
     vtx: VertexRef;                    # Vertex to convert
     db: AristoDbRef;                   # Database, top layer
@@ -176,18 +124,13 @@ proc updateAccountForHasher*(
     db: AristoDbRef;                   # Database
     hike: Hike;                        # Return value from `retrieveStorageID()`
       ) =
-  ## For a successful run of `retrieveStoAccHike()`, the argument `hike` is
-  ## used to mark/reset the keys along the `accPath` for being re-calculated
-  ## by `hashify()`.
+  ## The argument `hike` is used to mark/reset the keys along the implied
+  ## vertex path for being re-calculated.
   ##
   # Clear Merkle keys so that `hasify()` can calculate the re-hash forest/tree
   for w in hike.legs.mapIt(it.wp.vid):
     db.layersResKey(hike.root, w)
 
-  # Signal to `hashify()` where to start rebuilding Merkel hashes
-  # db.top.final.dirty.incl hike.root
-  # db.top.final.dirty.incl hike.legs[^1].wp.vid
-
 # ------------------------------------------------------------------------------
 # End
 # ------------------------------------------------------------------------------
diff --git a/nimbus/db/core_db/backend/aristo_db.nim b/nimbus/db/core_db/backend/aristo_db.nim
index 76341e08a..a406b2a14 100644
--- a/nimbus/db/core_db/backend/aristo_db.nim
+++ b/nimbus/db/core_db/backend/aristo_db.nim
@@ -243,12 +243,11 @@ func toAristo*(mBe: CoreDbAccBackendRef): AristoDbRef =
 
 proc toAristoSavedStateBlockNumber*(
     mBe: CoreDbMptBackendRef;
-      ): tuple[stateRoot: Hash256, blockNumber: BlockNumber] =
+      ): BlockNumber =
   if not mBe.isNil and mBe.parent.isAristo:
     let rc = mBe.parent.AristoCoreDbRef.adbBase.getSavedState()
     if rc.isOk:
-      return (rc.value.src.to(Hash256), rc.value.serial.BlockNumber)
-  (EMPTY_ROOT_HASH, 0.BlockNumber)
+      return rc.value.serial.BlockNumber
 
 # ------------------------------------------------------------------------------
 # Public aristo iterators
diff --git a/nimbus/db/core_db/core_apps.nim b/nimbus/db/core_db/core_apps.nim
index 33770e200..08099b9ce 100644
--- a/nimbus/db/core_db/core_apps.nim
+++ b/nimbus/db/core_db/core_apps.nim
@@ -334,20 +334,24 @@ proc getSavedStateBlockNumber*(
   ##
   ## This function verifies the state consistency of the database and throws
   ## an assert exception if that fails. So the function will only apply to a
-  ## finalised (aka hashified) database state. For an an opportunistic use,
-  ## the `relax` argument can be set `true` so this function also returns
-  ## zero if the state consistency check fails.
+  ## saved database state. For an an opportunistic use, the `relax` argument
+  ## can be set `true` so this function also returns the block number if the
+  ## state consistency check fails.
   ##
   const info = "getSavedStateBlockNumber(): "
-  var header: BlockHeader
-  let st = db.ctx.getColumn(CtGeneric).backend.toAristoSavedStateBlockNumber()
-  if db.getBlockHeader(st.blockNumber, header):
-    let state = db.ctx.getAccounts.state.valueOr:
-      raiseAssert info & $$error
-    if state == header.stateRoot:
-      return st.blockNumber
-    if not relax:
-      raiseAssert info & ": state mismatch at " & "#" & $st.blockNumber
+  # FIXME: This construct following will be replaced by a proper
+  #        `CoreDb` method.
+  let bn = db.ctx.getColumn(CtGeneric).backend.toAristoSavedStateBlockNumber()
+  if relax:
+    return bn
+  else:
+    var header: BlockHeader
+    if db.getBlockHeader(bn, header):
+      let state = db.ctx.getAccounts.state(updateOk=true).valueOr:
+        raiseAssert info & $$error
+      if state != header.stateRoot:
+        raiseAssert info & ": state mismatch at " & "#" & $result
+      return bn
 
 proc getBlockHeader*(
     db: CoreDbRef;
diff --git a/tests/test_aristo/test_filter.nim b/tests/test_aristo/test_filter.nim
index 13001c7b6..bda882e7d 100644
--- a/tests/test_aristo/test_filter.nim
+++ b/tests/test_aristo/test_filter.nim
@@ -12,7 +12,6 @@
 ##
 
 import
-  std/sets,
   eth/common,
   results,
   unittest2,
@@ -23,7 +22,6 @@ import
     aristo_debug,
     aristo_desc,
     aristo_get,
-    aristo_layers,
     aristo_persistent,
     aristo_tx],
   ../replay/xcheck,
@@ -170,8 +168,7 @@ proc isDbEq(a, b: LayerDeltaRef; db: AristoDbRef; noisy = true): bool =
   if b.isNil:
     return false
   if unsafeAddr(a[]) != unsafeAddr(b[]):
-    if a.src != b.src or
-       a.kMap.getOrVoid(testRootVid) != b.kMap.getOrVoid(testRootVid) or
+    if a.kMap.getOrVoid(testRootVid) != b.kMap.getOrVoid(testRootVid) or
        a.vTop != b.vTop:
       return false
 
diff --git a/tests/test_aristo/test_tx.nim b/tests/test_aristo/test_tx.nim
index c4ca07fae..3878848e9 100644
--- a/tests/test_aristo/test_tx.nim
+++ b/tests/test_aristo/test_tx.nim
@@ -155,9 +155,6 @@ proc saveToBackend(
     let rc = tx.commit()
     xCheckRc rc.error == 0
 
-  # Make sure MPT hashes are OK
-  xCheck db.dirty.len == 0
-
   block:
     let rc = db.txTop()
     xCheckRc rc.error == 0
@@ -175,9 +172,6 @@ proc saveToBackend(
     let rc = tx.commit()
     xCheckRc rc.error == 0
 
-  # Make sure MPT hashes are OK
-  xCheck db.dirty.len == 0
-
   block:
     let rc = db.txTop()
     xCheckErr rc.value.level < 0 # force error
@@ -213,9 +207,6 @@ proc saveToBackendWithOops(
     let rc = tx.commit()
     xCheckRc rc.error == 0
 
-  # Make sure MPT hashes are OK
-  xCheck db.dirty.len == 0
-
   block:
     let rc = db.txTop()
     xCheckRc rc.error == 0
@@ -229,9 +220,6 @@ proc saveToBackendWithOops(
     let rc = tx.commit()
     xCheckRc rc.error == 0
 
-  # Make sure MPT hashes are OK
-  xCheck db.dirty.len == 0
-
   block:
     let rc = db.txTop()
     xCheckErr rc.value.level < 0 # force error
diff --git a/tests/test_coredb/coredb_test_xx.nim b/tests/test_coredb/coredb_test_xx.nim
index 97103a56c..36b20be72 100644
--- a/tests/test_coredb/coredb_test_xx.nim
+++ b/tests/test_coredb/coredb_test_xx.nim
@@ -87,7 +87,7 @@ let
   mainTest0m* = mainSample
     .cloneWith(
       name      = "-am-some",
-      numBlocks = 5) # 1_000)
+      numBlocks = 1_000)
 
   mainTest1m* = mainSample
     .cloneWith(