anchor.diff:                              let! results = 
                                   partitions 
                                   |> Array.map (fun partitionId -> createTask partitionId collectorf) 
  -                                |> Partitions.ofArray workerCount
  -                                |> Array.map (fun wfs -> wfs |> Cloud.Parallel |> Cloud.ToSequential )
  -                                |> Cloud.Parallel
  -                            return Array.reduce combiner (Array.concat results)
  +                                |> parallelInChunks workerCount
  +                            return Array.reduce combiner results
                               
                   } }
   
  
positive.code:                     let! slice = (cached :> CloudArray<'T>).GetPartition(pid)
                      CloudArrayCache.Add(cached, pid, slice)
                  }
              let taskId = Guid.NewGuid().ToString()
              let cached = new CachedCloudArray<'T>(source, taskId)
              if source.Length > 0L then
                  let partitions = [|0..source.PartitionCount-1|]
                  do! partitions 
                      |> Array.map (fun pid -> createTask pid cached) 
                      |> Cloud.Parallel
                      |> Cloud.Ignore
              return cached :> _
          }
  
negative.code:         | Sequential  -> return failwith "Invalid CloudStream context : %A" ctx
          | ThreadParallel -> return 1
          | Distributed -> return! Cloud.GetWorkerCount()
      }
  
      /// Flat map/reduce with sequential execution on leafs.
      let inline private parallelInChunks (npar : int) (workflows : Cloud<'T> []) = cloud {
          let! partials = 
              workflows 
              |> Partitions.ofArray npar
              |> Array.map (fun wfs -> wfs |> Cloud.Parallel |> Cloud.ToSequential)
              |> Cloud.Parallel
          return Array.concat partials
      }
  
      /// <summary>Wraps array as a CloudStream.</summary>
  