diff --git a/torba/basedatabase.py b/torba/basedatabase.py
index 63bedf7b3..05ad53197 100644
--- a/torba/basedatabase.py
+++ b/torba/basedatabase.py
@@ -110,10 +110,9 @@ class SQLiteMixin:
 
     async def open(self):
         log.info("connecting to database: %s", self._db_path)
-        self.db = aiosqlite.connect(self._db_path)
+        self.db = aiosqlite.connect(self._db_path, isolation_level=None)
         await self.db.__aenter__()
         await self.db.executescript(self.CREATE_TABLES_QUERY)
-        await self.db.commit()
 
     async def close(self):
         await self.db.close()
@@ -273,7 +272,6 @@ class BaseDatabase(SQLiteMixin):
                 }))
 
         await self._set_address_history(address, history)
-        await self.db.commit()
 
     async def reserve_outputs(self, txos, is_reserved=True):
         txoids = [txo.id for txo in txos]
@@ -282,7 +280,6 @@ class BaseDatabase(SQLiteMixin):
                 ', '.join(['?']*len(txoids))
             ), [is_reserved]+txoids
         )
-        await self.db.commit()
 
     async def release_outputs(self, txos):
         await self.reserve_outputs(txos, is_reserved=False)
@@ -454,7 +451,6 @@ class BaseDatabase(SQLiteMixin):
                 sqlite3.Binary(pubkey.pubkey_bytes)
             ))
         await self.db.execute(sql, values)
-        await self.db.commit()
 
     async def _set_address_history(self, address, history):
         await self.db.execute(
@@ -464,4 +460,3 @@ class BaseDatabase(SQLiteMixin):
 
     async def set_address_history(self, address, history):
         await self._set_address_history(address, history)
-        await self.db.commit()
diff --git a/torba/baseledger.py b/torba/baseledger.py
index 481c94630..c22df65dc 100644
--- a/torba/baseledger.py
+++ b/torba/baseledger.py
@@ -306,17 +306,13 @@ class BaseLedger(metaclass=LedgerRegistry):
         ))
 
     async def update_account(self, account: baseaccount.BaseAccount):
-        # Before subscribing, download history for any addresses that don't have any,
-        # this avoids situation where we're getting status updates to addresses we know
-        # need to update anyways. Continue to get history and create more addresses until
-        # all missing addresses are created and history for them is fully restored.
         await account.ensure_address_gap()
         addresses = await account.get_addresses(used_times=0)
         while addresses:
             await asyncio.gather(*(self.subscribe_history(a) for a in addresses))
             addresses = await account.ensure_address_gap()
 
-    async def _prefetch_history(self, remote_history, local_history):
+    def _prefetch_history(self, remote_history, local_history):
         proofs, network_txs = {}, {}
         for i, (hex_id, remote_height) in enumerate(map(itemgetter('tx_hash', 'height'), remote_history)):
             if i < len(local_history) and local_history[i] == (hex_id, remote_height):
@@ -329,7 +325,7 @@ class BaseLedger(metaclass=LedgerRegistry):
     async def update_history(self, address):
         remote_history = await self.network.get_history(address)
         local_history = await self.get_local_history(address)
-        proofs, network_txs = await self._prefetch_history(remote_history, local_history)
+        proofs, network_txs = self._prefetch_history(remote_history, local_history)
 
         synced_history = StringIO()
         for i, (hex_id, remote_height) in enumerate(map(itemgetter('tx_hash', 'height'), remote_history)):