diff --git a/hbs2-core/lib/HBS2/Actors/ChunkWriter.hs b/hbs2-core/lib/HBS2/Actors/ChunkWriter.hs
index 3ddf1488..5a9d8792 100644
--- a/hbs2-core/lib/HBS2/Actors/ChunkWriter.hs
+++ b/hbs2-core/lib/HBS2/Actors/ChunkWriter.hs
@@ -9,6 +9,7 @@ module HBS2.Actors.ChunkWriter
   , commitBlock
   , writeChunk
   , getHash
+  , blocksInProcess
   ) where
 
 import HBS2.Prelude
@@ -70,6 +71,11 @@ data ChunkWriter h m = forall a . ( MonadIO m
   }
 
 
+blocksInProcess :: MonadIO m => ChunkWriter h m -> m Int
+blocksInProcess cw = liftIO $ Cache.purgeExpired cache >> Cache.size cache
+  where
+   cache = perBlock cw
+
 runChunkWriter :: forall h m . ( Eq (Hash h)
                                 , Hashable (Hash h)
                                 , MonadIO m )