Hi! I'm trying to profile the code pasted below. Per the profiler output it takes about 30% of my program running time and I'd like to analyze it further. What I need is a breakdown on a finer level, so I inserted SCC annotations. However, they appear to have attributed zero cost. I use GHC 6.8.2 on FreeBSD, the code is compiled without -O options. What am I doing wrong? Note: I'm not trying to *optimize* this code (I intuitively know where the problems are). My intention is to learn the mechanics of profiling Haskell code. serialize :: Database -> [[String]] serialize (dmap, tmap) = [ {-# SCC "XXX1" #-} [dbFormatTag], {-# SCC "XXX2" #-} (dumpWith docToStr dmap), {-# SCC "XXX3" #-} (dumpWith termToStr tmap) ] where dumpWith f = Data.Map.foldWithKey f [] docToStr k (Doc { docName=n, docVectorLength=vl}) = (:) ("d " ++ show k ++ " " ++ n ++ " " ++ (show vl)) termToStr t il = (:) ("t " ++ t ++ " " ++ (foldl ilItemToStr "" il)) ilItemToStr acc (docid, weight) = show docid ++ ":" ++ show weight ++ " " ++ acc -- Vlad Skvortsov, vss@73rus.com, http://vss.73rus.com