go-ethereum/triedb
CPerezz fcc0587ec3
core/state,triedb/pathdb: fix bintrieFlatReader disk-layer shape via per-offset extraction
Addresses review finding C2 (+ I5, S5, T2, T3, T12).

Before this commit, bintrieFlatCodec.ReadAccount returned the FULL
variable-length stem blob from disk while the in-memory diff-layer
buffer stored per-offset 32-byte values. The consumer,
bintrieFlatReader.Account, enforced len(basicBlob)!=32 → error, so
every disk-layer hit produced "bintrie BasicData leaf invalid length"
in production the moment the write buffer flushed. TestBintrieFlatReaderEndToEnd
did not catch this because it never forced a buffer → disk flush.

Fix: make bintrieFlatCodec.ReadAccount extract the offset from the
stem blob (mirroring ReadStorage), so the disk path and the buffer
path return the same 32-byte per-offset shape. Update
AccountCacheKey/StorageCacheKey to embed the full 32-byte key
(prefix + 31-byte stem + 1-byte offset), since caching under a
stem-only key would collapse BasicData and CodeHash into the same
slot and return the wrong value on the second hit. Update
Flush's cache-update loop to store per-offset entries from the
aggregated write set.

Design note: I considered the alternative of introducing a new
StemBlob(stem) interface method that returns the full blob synthesized
from a stem-level lookup index. Rejected because (a) the index is a
new data structure with its own consistency invariants, (b) the
per-offset approach is strictly local to the codec + reader, and (c)
the "1 Pebble read per Account" locality benefit is preserved at the
OS page cache level — both offsets at the same stem live in the same
Pebble block, so the second read is effectively free.

bintrieFlatReader.Account still does two AccountRLP lookups; the
torn-read hazard is gated by a new load-bearing invariant test,
TestBinaryHasherWritesBothBasicAndCodeHash, which asserts that
binaryHasher.updateAccount always emits both BasicData and CodeHash
leaves together. A future code-only update that broke this invariant
would fail the test.

Tests added:
  * TestBintrieFlatReaderEndToEndAfterFlush — explicitly flushes via
    tdb.Commit(root, false) and re-reads through a fresh StateReader.
    This is the smoking-gun regression for C2.
  * TestBintrieFlatReaderMultipleOffsetsPerStem — multiple offsets at
    the same stem (BasicData, CodeHash, header storage slots) all
    round-trip post-flush.
  * TestBintrieCodecCrossFlushRMW — two Flush calls to the same stem
    from different "blocks" correctly merge on disk, with prior
    offsets preserved.
  * TestBinaryHasherWritesBothBasicAndCodeHash — locks down the hasher
    co-write invariant that bintrieFlatReader.Account relies on.

Existing tests updated to match the new per-offset ReadAccount
semantics:
  * TestBintrieCodecAccountRoundTrip, TestBintrieCodecMultipleWritesSameStem,
    TestBintrieCodecDeleteAccount — now read per-offset rather than
    calling extractStemOffset on the raw blob.
  * TestBintrieCodecCacheKeysDisjoint — additionally verifies two
    offsets at the same stem produce distinct cache keys.

Error messages in bintrieFlatReader now include address and length
context (S5).
2026-04-15 15:00:40 +02:00
..
database trie: optimize memory allocation (#30932) 2025-03-25 14:59:44 +01:00
hashdb core, miner, tests: introduce codedb and simplify cachingDB (#33816) 2026-03-10 08:29:21 +01:00
internal triedb, triedb/internal, triedb/pathdb: add GenerateTrie + extract shared pipeline into triedb/internal (#34654) 2026-04-07 14:36:53 +08:00
pathdb core/state,triedb/pathdb: fix bintrieFlatReader disk-layer shape via per-offset extraction 2026-04-15 15:00:40 +02:00
database.go core, eth, ethclient, triedb: report trienode index progress (#34633) 2026-04-04 21:00:07 +08:00
generate.go triedb, triedb/internal, triedb/pathdb: add GenerateTrie + extract shared pipeline into triedb/internal (#34654) 2026-04-07 14:36:53 +08:00
generate_test.go triedb, triedb/internal, triedb/pathdb: add GenerateTrie + extract shared pipeline into triedb/internal (#34654) 2026-04-07 14:36:53 +08:00
history.go cmd, triedb: implement history inspection (#29267) 2024-03-22 20:12:10 +08:00
preimages.go all: remove the dependency from trie to triedb (#28824) 2024-02-13 14:49:53 +01:00
preimages_test.go triedb: add test suite for preimage store (#31574) 2025-05-05 14:01:53 +08:00
states.go all: update license comments and AUTHORS (#31133) 2025-02-05 23:01:17 +01:00