src/Ganeti/HTools/Cluster/Metrics.hs

{-# LANGUAGE TemplateHaskell #-}

{-| Implementation of the cluster metric

-}

{-

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module Ganeti.HTools.Cluster.Metrics
  ( ClusterStatistics
  , compCV
  , compCVfromStats
  , compCVNodes
  , compClusterStatistics
  , updateClusterStatisticsTwice
  , optimalCVScore
  , printStats
  ) where

import qualified Ganeti.HTools.Container as Container
import qualified Ganeti.HTools.Node as Node
import qualified Ganeti.HTools.Cluster.MetricsComponents as M
import Ganeti.HTools.Cluster.MetricsTH

$(declareStatistics M.metricComponents)

-- | Update a cluster statistics twice.
updateClusterStatisticsTwice :: ClusterStatistics
                                -> (Node.Node, Node.Node)
                                -> (Node.Node, Node.Node)
                                -> ClusterStatistics
updateClusterStatisticsTwice s a =
  updateClusterStatistics (updateClusterStatistics s a)

-- | Compute the total cluster store given the nodes.
compCVNodes :: [Node.Node] -> Double
compCVNodes = compCVfromStats . compClusterStatistics

-- | Wrapper over 'compCVNodes' for callers that have a 'Node.List'.
compCV :: Node.List -> Double
compCV = compCVNodes . Container.elems

-- | Shows statistics for a given node list.
printStats :: String -> Node.List -> String
printStats lp =
  showClusterStatistics lp . compClusterStatistics . Container.elems