diff --git a/hbs2-peer/app/Brains.hs b/hbs2-peer/app/Brains.hs
index b9abdb33..0d86c793 100644
--- a/hbs2-peer/app/Brains.hs
+++ b/hbs2-peer/app/Brains.hs
@@ -315,6 +315,35 @@ instance ( Hashable (Peer e)
       r <- query @_ @(Only Int) conn [qc|select 1 from seen where hash = ? limit 1|] (Only h)
       pure $ not $ List.null r
 
+  brainsCacheBlockSize b pk ha s  = do
+    updateOP b $ do
+      let conn = view brainsDb b
+
+      let sql = [qc|
+         insert into blocksizecache (block,peer,size)
+         values(?,?,?)
+         on conflict (block,peer) do update set size = excluded.size
+      |]
+
+      void $ execute conn sql (hash,peer,s)
+
+    where
+      peer = show $ pretty (AsBase58 pk)
+      hash = show $ pretty ha
+
+  brainsFindBlockSize brains pk ha = do
+     let conn = view brainsDb brains
+     let peer = show $ pretty (AsBase58 pk)
+     let hash = show $ pretty ha
+     liftIO do
+       result <- query @_ @(Only Integer) conn [qc|
+         select size
+         from blocksizecache
+         where block = ? and peer = ?
+         limit 1
+       |] (hash, peer)
+       pure $ fromOnly <$> listToMaybe result
+
 commitNow :: forall e m . MonadIO m
           => BasicBrains e
           -> Bool
@@ -624,6 +653,7 @@ SAVEPOINT zzz1;
 DELETE FROM ancestors WHERE strftime('%s','now') - strftime('%s', ts) > 600;
 DELETE FROM seenby WHERE strftime('%s','now') - strftime('%s', ts) > 600;
 DELETE FROM blocksize WHERE strftime('%s','now') - strftime('%s', ts) > (86400*7);
+DELETE FROM blocksizecache WHERE strftime('%s','now') - strftime('%s', ts) > (86400*7);
 DELETE FROM statedb.pexinfo where seen <  datetime('now', '-7 days');
 DELETE FROM seen where ts < datetime('now');
 
@@ -868,7 +898,7 @@ newBasicBrains cfg = liftIO do
   |]
 
   execute_ conn [qc|
-    create table if not exists blocksize2
+    create table if not exists blocksizecache
     ( block text not null
     , peer text not null
     , size int
diff --git a/hbs2-peer/app/RPC2.hs b/hbs2-peer/app/RPC2.hs
index 622d2adc..5f87c2b9 100644
--- a/hbs2-peer/app/RPC2.hs
+++ b/hbs2-peer/app/RPC2.hs
@@ -27,6 +27,7 @@ import HBS2.Actors.Peer
 import HBS2.Peer.Proto.Peer
 import HBS2.Peer.Proto.BlockInfo
 import HBS2.Peer.Proto.BlockChunks
+import HBS2.Peer.Brains
 import HBS2.Storage
 import HBS2.Clock
 import HBS2.Net.Auth.Schema
@@ -105,6 +106,10 @@ instance BlockSizeCache e () where
   cacheBlockSize _ _ _ _ = pure ()
   findBlockSize _ _ _ = pure Nothing
 
+instance BlockSizeCache e (SomeBrains e) where
+  cacheBlockSize = brainsCacheBlockSize @e
+  findBlockSize = brainsFindBlockSize @e
+
 queryBlockSizeFromPeer :: forall e cache m . ( e ~ L4Proto
                                              , MonadUnliftIO m
                                              , BlockSizeCache e cache
@@ -119,23 +124,33 @@ queryBlockSizeFromPeer cache e h peer = do
 
   what <- try @_ @(DownloadError e) $ liftIO $ withPeerM e do
 
-    PeerData{..} <- find (KnownPeerKey peer) id
-                     >>= orThrow (UnknownPeerError peer)
+    flip runContT pure $ callCC \exit -> do
 
-    sizeQ <- newTQueueIO
+      PeerData{..} <- lift $ find (KnownPeerKey peer) id
+                       >>= orThrow (UnknownPeerError peer)
 
-    subscribe @e (BlockSizeEventKey peer) $ \case
-      BlockSizeEvent (that, hx, sz) | hx == h -> do
-        atomically $ writeTQueue sizeQ (Just sz)
-        cacheBlockSize @e cache _peerSignKey h sz
+      s <- lift $ findBlockSize @e cache _peerSignKey h
 
-      _ -> do
-        atomically $ writeTQueue sizeQ Nothing
+      debug $ "FOUND CACHED VALUE" <+> pretty h <+> pretty s
 
-    request peer (GetBlockSize @e h)
+      maybe none (exit . Just) s
 
-    race ( pause defBlockInfoTimeout ) (atomically $ readTQueue sizeQ )
-       >>= orThrow (PeerRequestTimeout peer)
+      lift do
+
+        sizeQ <- newTQueueIO
+
+        subscribe @e (BlockSizeEventKey peer) $ \case
+          BlockSizeEvent (that, hx, sz) | hx == h -> do
+            atomically $ writeTQueue sizeQ (Just sz)
+            cacheBlockSize @e cache _peerSignKey h sz
+
+          _ -> do
+            atomically $ writeTQueue sizeQ Nothing
+
+        request peer (GetBlockSize @e h)
+
+        race ( pause defBlockInfoTimeout ) (atomically $ readTQueue sizeQ )
+           >>= orThrow (PeerRequestTimeout peer)
 
   case what of
     Left{}  -> pure $ Left (PeerRequestTimeout peer)
@@ -268,7 +283,7 @@ instance (e ~ L4Proto, MonadUnliftIO m, HasRpcContext PeerAPI RPC2Context m) =>
 
             peer <- either (const $ exit (mkSym "error:invalid-address")) pure peer'
 
-            what <- lift $ downloadFromPeer defChunkWaitMax () rpcPeerEnv (coerce blk) peer
+            what <- lift $ downloadFromPeer defChunkWaitMax rpcBrains rpcPeerEnv (coerce blk) peer
 
             case what of
               Left e   -> pure $ mkList @C [ mkSym "error" , mkStr (show e) ]
@@ -285,7 +300,7 @@ instance (e ~ L4Proto, MonadUnliftIO m, HasRpcContext PeerAPI RPC2Context m) =>
 
             peer <- either (const $ exit (mkSym "error:invalid-address")) pure peer'
 
-            sz <- lift $ queryBlockSizeFromPeer @e () rpcPeerEnv  (coerce blk) peer
+            sz <- lift $ queryBlockSizeFromPeer @e rpcBrains rpcPeerEnv  (coerce blk) peer
 
             case sz of
               Left e         -> pure $ mkList @C [ mkSym "error", mkStr (show e) ]
diff --git a/hbs2-peer/lib/HBS2/Peer/Brains.hs b/hbs2-peer/lib/HBS2/Peer/Brains.hs
index 8c16d230..f17cdbcd 100644
--- a/hbs2-peer/lib/HBS2/Peer/Brains.hs
+++ b/hbs2-peer/lib/HBS2/Peer/Brains.hs
@@ -67,6 +67,23 @@ class HasBrains e a where
   onKnownPeers :: MonadIO m => a -> [Peer e] -> m ()
   onKnownPeers _ _ = none
 
+  brainsCacheBlockSize :: MonadIO m
+                       => a
+                       -> PubKey 'Sign (Encryption e)
+                       -> Hash HbSync
+                       -> Integer
+                       -> m ()
+
+  brainsCacheBlockSize _ _ _ _ = none
+
+  brainsFindBlockSize :: MonadIO m
+                      => a
+                      -> PubKey 'Sign (Encryption e)
+                      -> Hash HbSync
+                      -> m (Maybe Integer)
+
+  brainsFindBlockSize _ _ _ = pure Nothing
+
   onBlockSize :: ( MonadIO m
                  , IsPeerAddr e m
                  )
@@ -197,3 +214,6 @@ instance HasBrains e (SomeBrains e) where
   setSeen (SomeBrains a) = setSeen @e a
   isSeen (SomeBrains a) = isSeen @e a
 
+  brainsCacheBlockSize (SomeBrains a) = brainsCacheBlockSize @e a
+  brainsFindBlockSize (SomeBrains a) = brainsFindBlockSize @e a
+