diff --git a/lbry/wallet/server/block_processor.py b/lbry/wallet/server/block_processor.py
index 7e469bd74..3661bb977 100644
--- a/lbry/wallet/server/block_processor.py
+++ b/lbry/wallet/server/block_processor.py
@@ -201,18 +201,28 @@ class BlockProcessor:
         return await asyncio.shield(run_in_thread())
 
     async def check_mempool(self):
-        current_mempool = {
-            k.tx_hash: v.raw_tx for (k, v) in self.db.prefix_db.mempool_tx.iterate()
-        }
+        def fetch_mempool(mempool_prefix):
+            return {
+                k.tx_hash: v.raw_tx for (k, v) in mempool_prefix.iterate()
+            }
+
+        def update_mempool(mempool_prefix, to_put, to_delete):
+            for tx_hash, raw_tx in to_put:
+                mempool_prefix.stage_put((tx_hash,), (raw_tx,))
+            for tx_hash, raw_tx in to_delete.items():
+                mempool_prefix.stage_delete((tx_hash,), (raw_tx,))
+
+        current_mempool = await self.run_in_thread_with_lock(fetch_mempool, self.db.prefix_db.mempool_tx)
+
+        _to_put = []
         for hh in await self.daemon.mempool_hashes():
             tx_hash = bytes.fromhex(hh)[::-1]
             if tx_hash in current_mempool:
                 current_mempool.pop(tx_hash)
             else:
-                raw_tx = bytes.fromhex(await self.daemon.getrawtransaction(hh))
-                self.db.prefix_db.mempool_tx.stage_put((tx_hash,), (raw_tx,))
-        for tx_hash, raw_tx in current_mempool.items():
-            self.db.prefix_db.mempool_tx.stage_delete((tx_hash,), (raw_tx,))
+                _to_put.append((tx_hash, bytes.fromhex(await self.daemon.getrawtransaction(hh))))
+
+        await self.run_in_thread_with_lock(update_mempool, self.db.prefix_db.mempool_tx, _to_put, current_mempool)
 
     async def check_and_advance_blocks(self, raw_blocks):
         """Process the list of raw blocks passed.  Detects and handles
@@ -1571,7 +1581,7 @@ class BlockProcessor:
                 if not blocks:
                     try:
                         await self.check_mempool()
-                        self.db.prefix_db.unsafe_commit()
+                        await self.run_in_thread_with_lock(self.db.prefix_db.unsafe_commit)
                     except Exception:
                         self.logger.exception("error while updating mempool txs")
                         raise