Add warning of witness presistence race condition

ethereum · Nov 20, 2020 · 1c2d53c · 1c2d53c
1 parent 24b1d54
commit 1c2d53c
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/trinity/protocol/wit/db.py b/trinity/protocol/wit/db.py
@@ -69,6 +69,10 @@ def persist_witness_hashes(
             recent_blocks_with_witnesses)
 
         try:
+            # Note: if this call is converted to async, watch out for the race
+            #   condition of two persists that interleave. It would be
+            #   possible for one to overwrite the other. For now, the synchronous
+            #   approach means that that isn't a concern.
             existing_hashes = self.get_witness_hashes(block_hash)
         except WitnessHashesUnavailable:
             existing_hashes = ()