-}
+{-
+
+Copyright (C) 2009 Google Inc.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.
+
+-}
+
module Ganeti.HTools.Cluster
(
-- * Types
- NodeList
- , InstanceList
- , NameList
- , Placement
- , Solution(..)
+ Placement
+ , AllocSolution
, Table(..)
- , Removal
- , Score
- , IMove(..)
+ , CStats(..)
-- * Generic functions
, totalResources
-- * First phase functions
, computeBadItems
-- * Second phase functions
- , computeSolution
- , applySolution
, printSolution
, printSolutionLine
, formatCmds
+ , involvedNodes
+ , splitJobs
+ -- * Display functions
, printNodes
+ , printInsts
-- * Balacing functions
- , applyMove
, checkMove
+ , tryBalance
, compCV
, printStats
+ , iMoveToJob
+ -- * IAllocator functions
+ , tryAlloc
+ , tryReloc
+ , collapseFailures
) where
import Data.List
-import Data.Maybe (isNothing, fromJust)
import Text.Printf (printf)
import Data.Function
import Control.Monad
import qualified Ganeti.HTools.Node as Node
import Ganeti.HTools.Types
import Ganeti.HTools.Utils
+import qualified Ganeti.OpCodes as OpCodes
--- | A separate name for the cluster score type
-type Score = Double
+-- * Types
--- | The description of an instance placement.
-type Placement = (Int, Int, Int, Score)
+-- | Allocation\/relocation solution.
+type AllocSolution = ([FailMode], Int, Maybe (Score, AllocElement))
-{- | A cluster solution described as the solution delta and the list
-of placements.
+-- | Allocation\/relocation element.
+type AllocElement = (Node.List, Instance.Instance, [Node.Node])
--}
-data Solution = Solution Int [Placement]
- deriving (Eq, Ord, Show)
-
--- | Returns the delta of a solution or -1 for Nothing
-solutionDelta :: Maybe Solution -> Int
-solutionDelta sol = case sol of
- Just (Solution d _) -> d
- _ -> -1
-
--- | A removal set.
-data Removal = Removal NodeList [Instance.Instance]
-
--- | An instance move definition
-data IMove = Failover -- ^ Failover the instance (f)
- | ReplacePrimary Int -- ^ Replace primary (f, r:np, f)
- | ReplaceSecondary Int -- ^ Replace secondary (r:ns)
- | ReplaceAndFailover Int -- ^ Replace secondary, failover (r:np, f)
- | FailoverAndReplace Int -- ^ Failover, replace secondary (f, r:ns)
- deriving (Show)
-- | The complete state for the balancing solution
-data Table = Table NodeList InstanceList Score [Placement]
+data Table = Table Node.List Instance.List Score [Placement]
deriving (Show)
--- General functions
-
--- | Cap the removal list if needed.
-capRemovals :: [a] -> Int -> [a]
-capRemovals removals max_removals =
- if max_removals > 0 then
- take max_removals removals
- else
- removals
-
--- | Check if the given node list fails the N+1 check.
-verifyN1Check :: [Node.Node] -> Bool
-verifyN1Check nl = any Node.failN1 nl
+data CStats = CStats { csFmem :: Int -- ^ Cluster free mem
+ , csFdsk :: Int -- ^ Cluster free disk
+ , csAmem :: Int -- ^ Cluster allocatable mem
+ , csAdsk :: Int -- ^ Cluster allocatable disk
+ , csAcpu :: Int -- ^ Cluster allocatable cpus
+ , csMmem :: Int -- ^ Max node allocatable mem
+ , csMdsk :: Int -- ^ Max node allocatable disk
+ , csMcpu :: Int -- ^ Max node allocatable cpu
+ , csImem :: Int -- ^ Instance used mem
+ , csIdsk :: Int -- ^ Instance used disk
+ , csIcpu :: Int -- ^ Instance used cpu
+ , csTmem :: Double -- ^ Cluster total mem
+ , csTdsk :: Double -- ^ Cluster total disk
+ , csTcpu :: Double -- ^ Cluster total cpus
+ , csXmem :: Int -- ^ Unnacounted for mem
+ , csNmem :: Int -- ^ Node own memory
+ , csScore :: Score -- ^ The cluster score
+ , csNinst :: Int -- ^ The total number of instances
+ }
+
+-- * Utility functions
-- | Verifies the N+1 status and return the affected nodes.
verifyN1 :: [Node.Node] -> [Node.Node]
-verifyN1 nl = filter Node.failN1 nl
-
-{-| Add an instance and return the new node and instance maps. -}
-addInstance :: NodeList -> Instance.Instance ->
- Node.Node -> Node.Node -> Maybe NodeList
-addInstance nl idata pri sec =
- let pdx = Node.idx pri
- sdx = Node.idx sec
- in do
- pnode <- Node.addPri pri idata
- snode <- Node.addSec sec idata pdx
- new_nl <- return $ Container.addTwo sdx snode
- pdx pnode nl
- return new_nl
-
--- | Remove an instance and return the new node and instance maps.
-removeInstance :: NodeList -> Instance.Instance -> NodeList
-removeInstance nl idata =
- let pnode = Instance.pnode idata
- snode = Instance.snode idata
- pn = Container.find pnode nl
- sn = Container.find snode nl
- new_nl = Container.addTwo
- pnode (Node.removePri pn idata)
- snode (Node.removeSec sn idata) nl in
- new_nl
-
--- | Remove an instance and return the new node map.
-removeInstances :: NodeList -> [Instance.Instance] -> NodeList
-removeInstances = foldl' removeInstance
-
--- | Compute the total free disk and memory in the cluster.
-totalResources :: Container.Container Node.Node -> (Int, Int)
-totalResources nl =
- foldl'
- (\ (mem, dsk) node -> (mem + (Node.f_mem node),
- dsk + (Node.f_dsk node)))
- (0, 0) (Container.elems nl)
-
-{- | Compute a new version of a cluster given a solution.
-
-This is not used for computing the solutions, but for applying a
-(known-good) solution to the original cluster for final display.
-
-It first removes the relocated instances after which it places them on
-their new nodes.
-
- -}
-applySolution :: NodeList -> InstanceList -> [Placement] -> NodeList
-applySolution nl il sol =
- let odxes = map (\ (a, b, c, _) -> (Container.find a il,
- Node.idx (Container.find b nl),
- Node.idx (Container.find c nl))
- ) sol
- idxes = (\ (x, _, _) -> x) (unzip3 odxes)
- nc = removeInstances nl idxes
- in
- foldl' (\ nz (a, b, c) ->
- let new_p = Container.find b nz
- new_s = Container.find c nz in
- fromJust (addInstance nz a new_p new_s)
- ) nc odxes
-
-
--- First phase functions
+verifyN1 = filter Node.failN1
-{- | Given a list 1,2,3..n build a list of pairs [(1, [2..n]), (2,
- [3..n]), ...]
-
--}
-genParts :: [a] -> Int -> [(a, [a])]
-genParts l count =
- case l of
- [] -> []
- x:xs ->
- if length l < count then
- []
- else
- (x, xs) : (genParts xs count)
-
--- | Generates combinations of count items from the names list.
-genNames :: Int -> [b] -> [[b]]
-genNames count1 names1 =
- let aux_fn count names current =
- case count of
- 0 -> [current]
- _ ->
- concatMap
- (\ (x, xs) -> aux_fn (count - 1) xs (x:current))
- (genParts names count)
- in
- aux_fn count1 names1 []
-
-{- | Computes the pair of bad nodes and instances.
+{-| Computes the pair of bad nodes and instances.
The bad node list is computed via a simple 'verifyN1' check, and the
bad instance list is the list of primary and secondary instances of
those nodes.
-}
-computeBadItems :: NodeList -> InstanceList ->
+computeBadItems :: Node.List -> Instance.List ->
([Node.Node], [Instance.Instance])
computeBadItems nl il =
- let bad_nodes = verifyN1 $ filter (not . Node.offline) $ Container.elems nl
- bad_instances = map (\idx -> Container.find idx il) $
- sort $ nub $ concat $
- map (\ n -> (Node.slist n) ++ (Node.plist n)) bad_nodes
+ let bad_nodes = verifyN1 $ getOnline nl
+ bad_instances = map (\idx -> Container.find idx il) .
+ sort . nub $
+ concatMap (\ n -> Node.sList n ++ Node.pList n) bad_nodes
in
(bad_nodes, bad_instances)
+emptyCStats :: CStats
+emptyCStats = CStats { csFmem = 0
+ , csFdsk = 0
+ , csAmem = 0
+ , csAdsk = 0
+ , csAcpu = 0
+ , csMmem = 0
+ , csMdsk = 0
+ , csMcpu = 0
+ , csImem = 0
+ , csIdsk = 0
+ , csIcpu = 0
+ , csTmem = 0
+ , csTdsk = 0
+ , csTcpu = 0
+ , csXmem = 0
+ , csNmem = 0
+ , csScore = 0
+ , csNinst = 0
+ }
+
+updateCStats :: CStats -> Node.Node -> CStats
+updateCStats cs node =
+ let CStats { csFmem = x_fmem, csFdsk = x_fdsk,
+ csAmem = x_amem, csAcpu = x_acpu, csAdsk = x_adsk,
+ csMmem = x_mmem, csMdsk = x_mdsk, csMcpu = x_mcpu,
+ csImem = x_imem, csIdsk = x_idsk, csIcpu = x_icpu,
+ csTmem = x_tmem, csTdsk = x_tdsk, csTcpu = x_tcpu,
+ csXmem = x_xmem, csNmem = x_nmem, csNinst = x_ninst
+ }
+ = cs
+ inc_amem = Node.fMem node - Node.rMem node
+ inc_amem' = if inc_amem > 0 then inc_amem else 0
+ inc_adsk = Node.availDisk node
+ inc_imem = truncate (Node.tMem node) - Node.nMem node
+ - Node.xMem node - Node.fMem node
+ inc_icpu = Node.uCpu node
+ inc_idsk = truncate (Node.tDsk node) - Node.fDsk node
+
+ in cs { csFmem = x_fmem + Node.fMem node
+ , csFdsk = x_fdsk + Node.fDsk node
+ , csAmem = x_amem + inc_amem'
+ , csAdsk = x_adsk + inc_adsk
+ , csAcpu = x_acpu
+ , csMmem = max x_mmem inc_amem'
+ , csMdsk = max x_mdsk inc_adsk
+ , csMcpu = x_mcpu
+ , csImem = x_imem + inc_imem
+ , csIdsk = x_idsk + inc_idsk
+ , csIcpu = x_icpu + inc_icpu
+ , csTmem = x_tmem + Node.tMem node
+ , csTdsk = x_tdsk + Node.tDsk node
+ , csTcpu = x_tcpu + Node.tCpu node
+ , csXmem = x_xmem + Node.xMem node
+ , csNmem = x_nmem + Node.nMem node
+ , csNinst = x_ninst + length (Node.pList node)
+ }
-{- | Checks if removal of instances results in N+1 pass.
-
-Note: the check removal cannot optimize by scanning only the affected
-nodes, since the cluster is known to be not healthy; only the check
-placement can make this shortcut.
+-- | Compute the total free disk and memory in the cluster.
+totalResources :: Node.List -> CStats
+totalResources nl =
+ let cs = foldl' updateCStats emptyCStats . Container.elems $ nl
+ in cs { csScore = compCV nl }
+
+-- | The names of the individual elements in the CV list
+detailedCVNames :: [String]
+detailedCVNames = [ "free_mem_cv"
+ , "free_disk_cv"
+ , "n1_score"
+ , "reserved_mem_cv"
+ , "offline_score"
+ , "vcpu_ratio_cv"
+ , "cpu_load_cv"
+ , "mem_load_cv"
+ , "disk_load_cv"
+ , "net_load_cv"
+ ]
--}
-checkRemoval :: NodeList -> [Instance.Instance] -> Maybe Removal
-checkRemoval nl victims =
- let nx = removeInstances nl victims
- failN1 = verifyN1Check (Container.elems nx)
- in
- if failN1 then
- Nothing
- else
- Just $ Removal nx victims
-
-
--- | Computes the removals list for a given depth
-computeRemovals :: NodeList
- -> [Instance.Instance]
- -> Int
- -> [Maybe Removal]
-computeRemovals nl bad_instances depth =
- map (checkRemoval nl) $ genNames depth bad_instances
-
--- Second phase functions
-
--- | Single-node relocation cost
-nodeDelta :: Int -> Int -> Int -> Int
-nodeDelta i p s =
- if i == p || i == s then
- 0
- else
- 1
-
-{-| Compute best solution.
-
- This function compares two solutions, choosing the minimum valid
- solution.
--}
-compareSolutions :: Maybe Solution -> Maybe Solution -> Maybe Solution
-compareSolutions a b = case (a, b) of
- (Nothing, x) -> x
- (x, Nothing) -> x
- (x, y) -> min x y
+-- | Compute the mem and disk covariance.
+compDetailedCV :: Node.List -> [Double]
+compDetailedCV nl =
+ let
+ all_nodes = Container.elems nl
+ (offline, nodes) = partition Node.offline all_nodes
+ mem_l = map Node.pMem nodes
+ dsk_l = map Node.pDsk nodes
+ mem_cv = varianceCoeff mem_l
+ dsk_cv = varianceCoeff dsk_l
+ n1_l = length $ filter Node.failN1 nodes
+ n1_score = fromIntegral n1_l /
+ fromIntegral (length nodes)::Double
+ res_l = map Node.pRem nodes
+ res_cv = varianceCoeff res_l
+ offline_inst = sum . map (\n -> (length . Node.pList $ n) +
+ (length . Node.sList $ n)) $ offline
+ online_inst = sum . map (\n -> (length . Node.pList $ n) +
+ (length . Node.sList $ n)) $ nodes
+ off_score = if offline_inst == 0
+ then 0::Double
+ else fromIntegral offline_inst /
+ fromIntegral (offline_inst + online_inst)::Double
+ cpu_l = map Node.pCpu nodes
+ cpu_cv = varianceCoeff cpu_l
+ (c_load, m_load, d_load, n_load) = unzip4 $
+ map (\n ->
+ let DynUtil c1 m1 d1 n1 = Node.utilLoad n
+ DynUtil c2 m2 d2 n2 = Node.utilPool n
+ in (c1/c2, m1/m2, d1/d2, n1/n2)
+ ) nodes
+ in [ mem_cv, dsk_cv, n1_score, res_cv, off_score, cpu_cv
+ , varianceCoeff c_load, varianceCoeff m_load
+ , varianceCoeff d_load, varianceCoeff n_load]
+
+-- | Compute the /total/ variance.
+compCV :: Node.List -> Double
+compCV = sum . compDetailedCV
+
+-- | Compute online nodes from a Node.List
+getOnline :: Node.List -> [Node.Node]
+getOnline = filter (not . Node.offline) . Container.elems
+
+-- * hbal functions
-- | Compute best table. Note that the ordering of the arguments is important.
compareTables :: Table -> Table -> Table
compareTables a@(Table _ _ a_cv _) b@(Table _ _ b_cv _ ) =
if a_cv > b_cv then b else a
--- | Check if a given delta is worse then an existing solution.
-tooHighDelta :: Maybe Solution -> Int -> Int -> Bool
-tooHighDelta sol new_delta max_delta =
- if new_delta > max_delta && max_delta >=0 then
- True
- else
- case sol of
- Nothing -> False
- Just (Solution old_delta _) -> old_delta <= new_delta
-
-{-| Check if placement of instances still keeps the cluster N+1 compliant.
-
- This is the workhorse of the allocation algorithm: given the
- current node and instance maps, the list of instances to be
- placed, and the current solution, this will return all possible
- solution by recursing until all target instances are placed.
-
--}
-checkPlacement :: NodeList -- ^ The current node list
- -> [Instance.Instance] -- ^ List of instances still to place
- -> [Placement] -- ^ Partial solution until now
- -> Int -- ^ The delta of the partial solution
- -> Maybe Solution -- ^ The previous solution
- -> Int -- ^ Abort if the we go above this delta
- -> Maybe Solution -- ^ The new solution
-checkPlacement nl victims current current_delta prev_sol max_delta =
- let target = head victims
- opdx = Instance.pnode target
- osdx = Instance.snode target
- vtail = tail victims
- have_tail = (length vtail) > 0
- nodes = Container.elems nl
- iidx = Instance.idx target
- in
- foldl'
- (\ accu_p pri ->
- let
- pri_idx = Node.idx pri
- upri_delta = current_delta + nodeDelta pri_idx opdx osdx
- new_pri = Node.addPri pri target
- fail_delta1 = tooHighDelta accu_p upri_delta max_delta
- in
- if fail_delta1 || isNothing(new_pri) then accu_p
- else let pri_nl = Container.add pri_idx (fromJust new_pri) nl in
- foldl'
- (\ accu sec ->
- let
- sec_idx = Node.idx sec
- upd_delta = upri_delta +
- nodeDelta sec_idx opdx osdx
- fail_delta2 = tooHighDelta accu upd_delta max_delta
- new_sec = Node.addSec sec target pri_idx
- in
- if sec_idx == pri_idx || fail_delta2 ||
- isNothing new_sec then accu
- else let
- nx = Container.add sec_idx (fromJust new_sec) pri_nl
- upd_cv = compCV nx
- plc = (iidx, pri_idx, sec_idx, upd_cv)
- c2 = plc:current
- result =
- if have_tail then
- checkPlacement nx vtail c2 upd_delta
- accu max_delta
- else
- Just (Solution upd_delta c2)
- in compareSolutions accu result
- ) accu_p nodes
- ) prev_sol nodes
-
--- | Apply a move
-applyMove :: NodeList -> Instance.Instance
- -> IMove -> (Maybe NodeList, Instance.Instance, Int, Int)
+-- | Applies an instance move to a given node list and instance.
+applyMove :: Node.List -> Instance.Instance
+ -> IMove -> OpResult (Node.List, Instance.Instance, Ndx, Ndx)
-- Failover (f)
applyMove nl inst Failover =
- let old_pdx = Instance.pnode inst
- old_sdx = Instance.snode inst
+ let old_pdx = Instance.pNode inst
+ old_sdx = Instance.sNode inst
old_p = Container.find old_pdx nl
old_s = Container.find old_sdx nl
int_p = Node.removePri old_p inst
new_nl = do -- Maybe monad
new_p <- Node.addPri int_s inst
new_s <- Node.addSec int_p inst old_sdx
- return $ Container.addTwo old_pdx new_s old_sdx new_p nl
- in (new_nl, Instance.setBoth inst old_sdx old_pdx, old_sdx, old_pdx)
+ let new_inst = Instance.setBoth inst old_sdx old_pdx
+ return (Container.addTwo old_pdx new_s old_sdx new_p nl,
+ new_inst, old_sdx, old_pdx)
+ in new_nl
-- Replace the primary (f:, r:np, f)
applyMove nl inst (ReplacePrimary new_pdx) =
- let old_pdx = Instance.pnode inst
- old_sdx = Instance.snode inst
+ let old_pdx = Instance.pNode inst
+ old_sdx = Instance.sNode inst
old_p = Container.find old_pdx nl
old_s = Container.find old_sdx nl
tgt_n = Container.find new_pdx nl
int_p = Node.removePri old_p inst
int_s = Node.removeSec old_s inst
new_nl = do -- Maybe monad
+ -- check that the current secondary can host the instance
+ -- during the migration
+ tmp_s <- Node.addPri int_s inst
+ let tmp_s' = Node.removePri tmp_s inst
new_p <- Node.addPri tgt_n inst
- new_s <- Node.addSec int_s inst new_pdx
- return $ Container.add new_pdx new_p $
- Container.addTwo old_pdx int_p old_sdx new_s nl
- in (new_nl, Instance.setPri inst new_pdx, new_pdx, old_sdx)
+ new_s <- Node.addSec tmp_s' inst new_pdx
+ let new_inst = Instance.setPri inst new_pdx
+ return (Container.add new_pdx new_p $
+ Container.addTwo old_pdx int_p old_sdx new_s nl,
+ new_inst, new_pdx, old_sdx)
+ in new_nl
-- Replace the secondary (r:ns)
applyMove nl inst (ReplaceSecondary new_sdx) =
- let old_pdx = Instance.pnode inst
- old_sdx = Instance.snode inst
+ let old_pdx = Instance.pNode inst
+ old_sdx = Instance.sNode inst
old_s = Container.find old_sdx nl
tgt_n = Container.find new_sdx nl
int_s = Node.removeSec old_s inst
+ new_inst = Instance.setSec inst new_sdx
new_nl = Node.addSec tgt_n inst old_pdx >>=
- \new_s -> return $ Container.addTwo new_sdx
- new_s old_sdx int_s nl
- in (new_nl, Instance.setSec inst new_sdx, old_pdx, new_sdx)
+ \new_s -> return (Container.addTwo new_sdx
+ new_s old_sdx int_s nl,
+ new_inst, old_pdx, new_sdx)
+ in new_nl
-- Replace the secondary and failover (r:np, f)
applyMove nl inst (ReplaceAndFailover new_pdx) =
- let old_pdx = Instance.pnode inst
- old_sdx = Instance.snode inst
+ let old_pdx = Instance.pNode inst
+ old_sdx = Instance.sNode inst
old_p = Container.find old_pdx nl
old_s = Container.find old_sdx nl
tgt_n = Container.find new_pdx nl
new_nl = do -- Maybe monad
new_p <- Node.addPri tgt_n inst
new_s <- Node.addSec int_p inst new_pdx
- return $ Container.add new_pdx new_p $
- Container.addTwo old_pdx new_s old_sdx int_s nl
- in (new_nl, Instance.setBoth inst new_pdx old_pdx, new_pdx, old_pdx)
+ let new_inst = Instance.setBoth inst new_pdx old_pdx
+ return (Container.add new_pdx new_p $
+ Container.addTwo old_pdx new_s old_sdx int_s nl,
+ new_inst, new_pdx, old_pdx)
+ in new_nl
-- Failver and replace the secondary (f, r:ns)
applyMove nl inst (FailoverAndReplace new_sdx) =
- let old_pdx = Instance.pnode inst
- old_sdx = Instance.snode inst
+ let old_pdx = Instance.pNode inst
+ old_sdx = Instance.sNode inst
old_p = Container.find old_pdx nl
old_s = Container.find old_sdx nl
tgt_n = Container.find new_sdx nl
new_nl = do -- Maybe monad
new_p <- Node.addPri int_s inst
new_s <- Node.addSec tgt_n inst old_sdx
- return $ Container.add new_sdx new_s $
- Container.addTwo old_sdx new_p old_pdx int_p nl
- in (new_nl, Instance.setBoth inst old_sdx new_sdx, old_sdx, new_sdx)
-
+ let new_inst = Instance.setBoth inst old_sdx new_sdx
+ return (Container.add new_sdx new_s $
+ Container.addTwo old_sdx new_p old_pdx int_p nl,
+ new_inst, old_sdx, new_sdx)
+ in new_nl
+
+-- | Tries to allocate an instance on one given node.
+allocateOnSingle :: Node.List -> Instance.Instance -> Node.Node
+ -> OpResult AllocElement
+allocateOnSingle nl inst p =
+ let new_pdx = Node.idx p
+ new_inst = Instance.setBoth inst new_pdx Node.noSecondary
+ new_nl = Node.addPri p inst >>= \new_p ->
+ return (Container.add new_pdx new_p nl, new_inst, [new_p])
+ in new_nl
+
+-- | Tries to allocate an instance on a given pair of nodes.
+allocateOnPair :: Node.List -> Instance.Instance -> Node.Node -> Node.Node
+ -> OpResult AllocElement
+allocateOnPair nl inst tgt_p tgt_s =
+ let new_pdx = Node.idx tgt_p
+ new_sdx = Node.idx tgt_s
+ new_nl = do -- Maybe monad
+ new_p <- Node.addPri tgt_p inst
+ new_s <- Node.addSec tgt_s inst new_pdx
+ let new_inst = Instance.setBoth inst new_pdx new_sdx
+ return (Container.addTwo new_pdx new_p new_sdx new_s nl, new_inst,
+ [new_p, new_s])
+ in new_nl
+
+-- | Tries to perform an instance move and returns the best table
+-- between the original one and the new one.
checkSingleStep :: Table -- ^ The original table
-> Instance.Instance -- ^ The instance to move
-> Table -- ^ The current best table
checkSingleStep ini_tbl target cur_tbl move =
let
Table ini_nl ini_il _ ini_plc = ini_tbl
- (tmp_nl, new_inst, pri_idx, sec_idx) = applyMove ini_nl target move
+ tmp_resu = applyMove ini_nl target move
in
- if isNothing tmp_nl then cur_tbl
- else
- let tgt_idx = Instance.idx target
- upd_nl = fromJust tmp_nl
- upd_cvar = compCV upd_nl
- upd_il = Container.add tgt_idx new_inst ini_il
- upd_plc = (tgt_idx, pri_idx, sec_idx, upd_cvar):ini_plc
- upd_tbl = Table upd_nl upd_il upd_cvar upd_plc
- in
- compareTables cur_tbl upd_tbl
-
--- | Given the status of the current secondary as a valid new node
--- and the current candidate target node,
--- generate the possible moves for a instance.
-possibleMoves :: Bool -> Int -> [IMove]
+ case tmp_resu of
+ OpFail _ -> cur_tbl
+ OpGood (upd_nl, new_inst, pri_idx, sec_idx) ->
+ let tgt_idx = Instance.idx target
+ upd_cvar = compCV upd_nl
+ upd_il = Container.add tgt_idx new_inst ini_il
+ upd_plc = (tgt_idx, pri_idx, sec_idx, move, upd_cvar):ini_plc
+ upd_tbl = Table upd_nl upd_il upd_cvar upd_plc
+ in
+ compareTables cur_tbl upd_tbl
+
+-- | Given the status of the current secondary as a valid new node and
+-- the current candidate target node, generate the possible moves for
+-- a instance.
+possibleMoves :: Bool -- ^ Whether the secondary node is a valid new node
+ -> Ndx -- ^ Target node candidate
+ -> [IMove] -- ^ List of valid result moves
possibleMoves True tdx =
[ReplaceSecondary tdx,
ReplaceAndFailover tdx,
ReplaceAndFailover tdx]
-- | Compute the best move for a given instance.
-checkInstanceMove :: [Int] -- Allowed target node indices
- -> Table -- Original table
- -> Instance.Instance -- Instance to move
- -> Table -- Best new table for this instance
-checkInstanceMove nodes_idx ini_tbl target =
+checkInstanceMove :: [Ndx] -- ^ Allowed target node indices
+ -> Bool -- ^ Whether disk moves are allowed
+ -> Table -- ^ Original table
+ -> Instance.Instance -- ^ Instance to move
+ -> Table -- ^ Best new table for this instance
+checkInstanceMove nodes_idx disk_moves ini_tbl target =
let
- opdx = Instance.pnode target
- osdx = Instance.snode target
+ opdx = Instance.pNode target
+ osdx = Instance.sNode target
nodes = filter (\idx -> idx /= opdx && idx /= osdx) nodes_idx
use_secondary = elem osdx nodes_idx
aft_failover = if use_secondary -- if allowed to failover
then checkSingleStep ini_tbl target ini_tbl Failover
else ini_tbl
- all_moves = concatMap (possibleMoves use_secondary) nodes
+ all_moves = if disk_moves
+ then concatMap (possibleMoves use_secondary) nodes
+ else []
in
-- iterate over the possible nodes for this instance
foldl' (checkSingleStep ini_tbl target) aft_failover all_moves
-- | Compute the best next move.
-checkMove :: [Int] -- ^ Allowed target node indices
+checkMove :: [Ndx] -- ^ Allowed target node indices
+ -> Bool -- ^ Whether disk moves are allowed
-> Table -- ^ The current solution
-> [Instance.Instance] -- ^ List of instances still to move
-> Table -- ^ The new solution
-checkMove nodes_idx ini_tbl victims =
+checkMove nodes_idx disk_moves ini_tbl victims =
let Table _ _ _ ini_plc = ini_tbl
-- iterate over all instances, computing the best move
best_tbl =
foldl'
- (\ step_tbl elem ->
- if Instance.snode elem == Node.noSecondary then step_tbl
+ (\ step_tbl em ->
+ if Instance.sNode em == Node.noSecondary then step_tbl
else compareTables step_tbl $
- checkInstanceMove nodes_idx ini_tbl elem)
+ checkInstanceMove nodes_idx disk_moves ini_tbl em)
ini_tbl victims
Table _ _ _ best_plc = best_tbl
in
else
best_tbl
-{- | Auxiliary function for solution computation.
-
-We write this in an explicit recursive fashion in order to control
-early-abort in case we have met the min delta. We can't use foldr
-instead of explicit recursion since we need the accumulator for the
-abort decision.
-
--}
-advanceSolution :: [Maybe Removal] -- ^ The removal to process
- -> Int -- ^ Minimum delta parameter
- -> Int -- ^ Maximum delta parameter
- -> Maybe Solution -- ^ Current best solution
- -> Maybe Solution -- ^ New best solution
-advanceSolution [] _ _ sol = sol
-advanceSolution (Nothing:xs) m n sol = advanceSolution xs m n sol
-advanceSolution ((Just (Removal nx removed)):xs) min_d max_d prev_sol =
- let new_sol = checkPlacement nx removed [] 0 prev_sol max_d
- new_delta = solutionDelta $! new_sol
+-- | Run a balance move
+
+tryBalance :: Table -- ^ The starting table
+ -> Int -- ^ Remaining length
+ -> Bool -- ^ Allow disk moves
+ -> Score -- ^ Score at which to stop
+ -> Maybe Table -- ^ The resulting table and commands
+tryBalance ini_tbl max_rounds disk_moves min_score =
+ let Table ini_nl ini_il ini_cv ini_plc = ini_tbl
+ ini_plc_len = length ini_plc
+ allowed_next = (max_rounds < 0 || ini_plc_len < max_rounds) &&
+ ini_cv > min_score
in
- if new_delta >= 0 && new_delta <= min_d then
- new_sol
- else
- advanceSolution xs min_d max_d new_sol
-
--- | Computes the placement solution.
-solutionFromRemovals :: [Maybe Removal] -- ^ The list of (possible) removals
- -> Int -- ^ Minimum delta parameter
- -> Int -- ^ Maximum delta parameter
- -> Maybe Solution -- ^ The best solution found
-solutionFromRemovals removals min_delta max_delta =
- advanceSolution removals min_delta max_delta Nothing
-
-{- | Computes the solution at the given depth.
-
-This is a wrapper over both computeRemovals and
-solutionFromRemovals. In case we have no solution, we return Nothing.
-
--}
-computeSolution :: NodeList -- ^ The original node data
- -> [Instance.Instance] -- ^ The list of /bad/ instances
- -> Int -- ^ The /depth/ of removals
- -> Int -- ^ Maximum number of removals to process
- -> Int -- ^ Minimum delta parameter
- -> Int -- ^ Maximum delta parameter
- -> Maybe Solution -- ^ The best solution found (or Nothing)
-computeSolution nl bad_instances depth max_removals min_delta max_delta =
- let
- removals = computeRemovals nl bad_instances depth
- removals' = capRemovals removals max_removals
- in
- solutionFromRemovals removals' min_delta max_delta
-
--- Solution display functions (pure)
+ if allowed_next
+ then let all_inst = Container.elems ini_il
+ node_idx = map Node.idx . filter (not . Node.offline) $
+ Container.elems ini_nl
+ fin_tbl = checkMove node_idx disk_moves ini_tbl all_inst
+ (Table _ _ fin_cv _) = fin_tbl
+ in
+ if fin_cv < ini_cv
+ then Just fin_tbl -- this round made success, try deeper
+ else Nothing
+ else Nothing
+
+-- * Allocation functions
+
+-- | Build failure stats out of a list of failures
+collapseFailures :: [FailMode] -> FailStats
+collapseFailures flst =
+ map (\k -> (k, length $ filter ((==) k) flst)) [minBound..maxBound]
+
+-- | Update current Allocation solution and failure stats with new
+-- elements
+concatAllocs :: AllocSolution -> OpResult AllocElement -> AllocSolution
+concatAllocs (flst, cntok, sols) (OpFail reason) = (reason:flst, cntok, sols)
+
+concatAllocs (flst, cntok, osols) (OpGood ns@(nl, _, _)) =
+ let nscore = compCV nl
+ -- Choose the old or new solution, based on the cluster score
+ nsols = case osols of
+ Nothing -> Just (nscore, ns)
+ Just (oscore, _) ->
+ if oscore < nscore
+ then osols
+ else Just (nscore, ns)
+ nsuc = cntok + 1
+ -- Note: we force evaluation of nsols here in order to keep the
+ -- memory profile low - we know that we will need nsols for sure
+ -- in the next cycle, so we force evaluation of nsols, since the
+ -- foldl' in the caller will only evaluate the tuple, but not the
+ -- elements of the tuple
+ in nsols `seq` nsuc `seq` (flst, nsuc, nsols)
+
+-- | Try to allocate an instance on the cluster.
+tryAlloc :: (Monad m) =>
+ Node.List -- ^ The node list
+ -> Instance.List -- ^ The instance list
+ -> Instance.Instance -- ^ The instance to allocate
+ -> Int -- ^ Required number of nodes
+ -> m AllocSolution -- ^ Possible solution list
+tryAlloc nl _ inst 2 =
+ let all_nodes = getOnline nl
+ all_pairs = liftM2 (,) all_nodes all_nodes
+ ok_pairs = filter (\(x, y) -> Node.idx x /= Node.idx y) all_pairs
+ sols = foldl' (\cstate (p, s) ->
+ concatAllocs cstate $ allocateOnPair nl inst p s
+ ) ([], 0, Nothing) ok_pairs
+ in return sols
+
+tryAlloc nl _ inst 1 =
+ let all_nodes = getOnline nl
+ sols = foldl' (\cstate ->
+ concatAllocs cstate . allocateOnSingle nl inst
+ ) ([], 0, Nothing) all_nodes
+ in return sols
+
+tryAlloc _ _ _ reqn = fail $ "Unsupported number of allocation \
+ \destinations required (" ++ show reqn ++
+ "), only two supported"
+
+-- | Try to allocate an instance on the cluster.
+tryReloc :: (Monad m) =>
+ Node.List -- ^ The node list
+ -> Instance.List -- ^ The instance list
+ -> Idx -- ^ The index of the instance to move
+ -> Int -- ^ The number of nodes required
+ -> [Ndx] -- ^ Nodes which should not be used
+ -> m AllocSolution -- ^ Solution list
+tryReloc nl il xid 1 ex_idx =
+ let all_nodes = getOnline nl
+ inst = Container.find xid il
+ ex_idx' = Instance.pNode inst:ex_idx
+ valid_nodes = filter (not . flip elem ex_idx' . Node.idx) all_nodes
+ valid_idxes = map Node.idx valid_nodes
+ sols1 = foldl' (\cstate x ->
+ let em = do
+ (mnl, i, _, _) <-
+ applyMove nl inst (ReplaceSecondary x)
+ return (mnl, i, [Container.find x mnl])
+ in concatAllocs cstate em
+ ) ([], 0, Nothing) valid_idxes
+ in return sols1
+
+tryReloc _ _ _ reqn _ = fail $ "Unsupported number of relocation \
+ \destinations required (" ++ show reqn ++
+ "), only one supported"
+
+-- * Formatting functions
-- | Given the original and final nodes, computes the relocation description.
-computeMoves :: String -- ^ The instance name
+computeMoves :: Instance.Instance -- ^ The instance to be moved
+ -> String -- ^ The instance name
-> String -- ^ Original primary
-> String -- ^ Original secondary
-> String -- ^ New primary
-- either @/f/@ for failover or @/r:name/@ for replace
-- secondary, while the command list holds gnt-instance
-- commands (without that prefix), e.g \"@failover instance1@\"
-computeMoves i a b c d =
- if c == a then {- Same primary -}
- if d == b then {- Same sec??! -}
- ("-", [])
+computeMoves i inam a b c d
+ -- same primary
+ | c == a =
+ if d == b
+ then {- Same sec??! -} ("-", [])
else {- Change of secondary -}
- (printf "r:%s" d,
- [printf "replace-disks -n %s %s" d i])
- else
- if c == b then {- Failover and ... -}
- if d == a then {- that's all -}
- ("f", [printf "migrate -f %s" i])
- else
- (printf "f r:%s" d,
- [printf "migrate -f %s" i,
- printf "replace-disks -n %s %s" d i])
- else
- if d == a then {- ... and keep primary as secondary -}
- (printf "r:%s f" c,
- [printf "replace-disks -n %s %s" c i,
- printf "migrate -f %s" i])
- else
- if d == b then {- ... keep same secondary -}
- (printf "f r:%s f" c,
- [printf "migrate -f %s" i,
- printf "replace-disks -n %s %s" c i,
- printf "migrate -f %s" i])
-
- else {- Nothing in common -}
- (printf "r:%s f r:%s" c d,
- [printf "replace-disks -n %s %s" c i,
- printf "migrate -f %s" i,
- printf "replace-disks -n %s %s" d i])
-
-{-| Converts a placement to string format -}
-printSolutionLine :: NodeList
- -> InstanceList
- -> Int
- -> Int
- -> Placement
- -> Int
+ (printf "r:%s" d, [rep d])
+ -- failover and ...
+ | c == b =
+ if d == a
+ then {- that's all -} ("f", [mig])
+ else (printf "f r:%s" d, [mig, rep d])
+ -- ... and keep primary as secondary
+ | d == a =
+ (printf "r:%s f" c, [rep c, mig])
+ -- ... keep same secondary
+ | d == b =
+ (printf "f r:%s f" c, [mig, rep c, mig])
+ -- nothing in common -
+ | otherwise =
+ (printf "r:%s f r:%s" c d, [rep c, mig, rep d])
+ where morf = if Instance.running i then "migrate" else "failover"
+ mig = printf "%s -f %s" morf inam::String
+ rep n = printf "replace-disks -n %s %s" n inam
+
+-- | Converts a placement to string format.
+printSolutionLine :: Node.List -- ^ The node list
+ -> Instance.List -- ^ The instance list
+ -> Int -- ^ Maximum node name length
+ -> Int -- ^ Maximum instance name length
+ -> Placement -- ^ The current placement
+ -> Int -- ^ The index of the placement in
+ -- the solution
-> (String, [String])
printSolutionLine nl il nmlen imlen plc pos =
let
pmlen = (2*nmlen + 1)
- (i, p, s, c) = plc
+ (i, p, s, _, c) = plc
inst = Container.find i il
inam = Instance.name inst
- npri = cNameOf nl p
- nsec = cNameOf nl s
- opri = cNameOf nl $ Instance.pnode inst
- osec = cNameOf nl $ Instance.snode inst
- (moves, cmds) = computeMoves inam opri osec npri nsec
- ostr = (printf "%s:%s" opri osec)::String
- nstr = (printf "%s:%s" npri nsec)::String
+ npri = Container.nameOf nl p
+ nsec = Container.nameOf nl s
+ opri = Container.nameOf nl $ Instance.pNode inst
+ osec = Container.nameOf nl $ Instance.sNode inst
+ (moves, cmds) = computeMoves inst inam opri osec npri nsec
+ ostr = printf "%s:%s" opri osec::String
+ nstr = printf "%s:%s" npri nsec::String
in
(printf " %3d. %-*s %-*s => %-*s %.8f a=%s"
pos imlen inam pmlen ostr
pmlen nstr c moves,
cmds)
-formatCmds :: [[String]] -> String
-formatCmds cmd_strs =
- unlines $
- concat $ map (\(a, b) ->
- (printf "echo step %d" (a::Int)):
- (printf "check"):
- (map ("gnt-instance " ++) b)) $
- zip [1..] cmd_strs
-
-{-| Converts a solution to string format -}
-printSolution :: NodeList
- -> InstanceList
+-- | Return the instance and involved nodes in an instance move.
+involvedNodes :: Instance.List -> Placement -> [Ndx]
+involvedNodes il plc =
+ let (i, np, ns, _, _) = plc
+ inst = Container.find i il
+ op = Instance.pNode inst
+ os = Instance.sNode inst
+ in nub [np, ns, op, os]
+
+-- | Inner function for splitJobs, that either appends the next job to
+-- the current jobset, or starts a new jobset.
+mergeJobs :: ([JobSet], [Ndx]) -> MoveJob -> ([JobSet], [Ndx])
+mergeJobs ([], _) n@(ndx, _, _, _) = ([[n]], ndx)
+mergeJobs (cjs@(j:js), nbuf) n@(ndx, _, _, _)
+ | null (ndx `intersect` nbuf) = ((n:j):js, ndx ++ nbuf)
+ | otherwise = ([n]:cjs, ndx)
+
+-- | Break a list of moves into independent groups. Note that this
+-- will reverse the order of jobs.
+splitJobs :: [MoveJob] -> [JobSet]
+splitJobs = fst . foldl mergeJobs ([], [])
+
+-- | Given a list of commands, prefix them with @gnt-instance@ and
+-- also beautify the display a little.
+formatJob :: Int -> Int -> (Int, MoveJob) -> [String]
+formatJob jsn jsl (sn, (_, _, _, cmds)) =
+ let out =
+ printf " echo job %d/%d" jsn sn:
+ printf " check":
+ map (" gnt-instance " ++) cmds
+ in if sn == 1
+ then ["", printf "echo jobset %d, %d jobs" jsn jsl] ++ out
+ else out
+
+-- | Given a list of commands, prefix them with @gnt-instance@ and
+-- also beautify the display a little.
+formatCmds :: [JobSet] -> String
+formatCmds =
+ unlines .
+ concatMap (\(jsn, js) -> concatMap (formatJob jsn (length js))
+ (zip [1..] js)) .
+ zip [1..]
+
+-- | Converts a solution to string format.
+printSolution :: Node.List
+ -> Instance.List
-> [Placement]
-> ([String], [[String]])
printSolution nl il sol =
let
- nmlen = cMaxNamelen nl
- imlen = cMaxNamelen il
+ nmlen = Container.maxNameLen nl
+ imlen = Container.maxNameLen il
in
- unzip $ map (uncurry $ printSolutionLine nl il nmlen imlen) $
- zip sol [1..]
+ unzip $ zipWith (printSolutionLine nl il nmlen imlen) sol [1..]
-- | Print the node list.
-printNodes :: NodeList -> String
+printNodes :: Node.List -> String
printNodes nl =
let snl = sortBy (compare `on` Node.idx) (Container.elems nl)
- m_name = maximum . map (length . Node.name) $ snl
- helper = Node.list m_name
- header = printf
- "%2s %-*s %5s %5s %5s %5s %5s %5s %5s %5s %3s %3s %7s %7s"
- " F" m_name "Name"
- "t_mem" "n_mem" "i_mem" "x_mem" "f_mem" "r_mem"
- "t_dsk" "f_dsk"
- "pri" "sec" "p_fmem" "p_fdsk"
- in unlines $ (header:map helper snl)
-
--- | Compute the mem and disk covariance.
-compDetailedCV :: NodeList -> (Double, Double, Double, Double, Double)
-compDetailedCV nl =
- let
- all_nodes = Container.elems nl
- (offline, nodes) = partition Node.offline all_nodes
- mem_l = map Node.p_mem nodes
- dsk_l = map Node.p_dsk nodes
- mem_cv = varianceCoeff mem_l
- dsk_cv = varianceCoeff dsk_l
- n1_l = length $ filter Node.failN1 nodes
- n1_score = (fromIntegral n1_l) / (fromIntegral $ length nodes)
- res_l = map Node.p_rem nodes
- res_cv = varianceCoeff res_l
- offline_inst = sum . map (\n -> (length . Node.plist $ n) +
- (length . Node.slist $ n)) $ offline
- online_inst = sum . map (\n -> (length . Node.plist $ n) +
- (length . Node.slist $ n)) $ nodes
- off_score = (fromIntegral offline_inst) /
- (fromIntegral $ online_inst + offline_inst)
- in (mem_cv, dsk_cv, n1_score, res_cv, off_score)
-
--- | Compute the 'total' variance.
-compCV :: NodeList -> Double
-compCV nl =
- let (mem_cv, dsk_cv, n1_score, res_cv, off_score) = compDetailedCV nl
- in mem_cv + dsk_cv + n1_score + res_cv + off_score
-
-printStats :: NodeList -> String
+ header = ["F", "Name"
+ , "t_mem", "n_mem", "i_mem", "x_mem", "f_mem", "r_mem"
+ , "t_dsk", "f_dsk", "pcpu", "vcpu", "pri", "sec"
+ , "p_fmem", "p_fdsk", "r_cpu"
+ , "lCpu", "lMem", "lDsk", "lNet" ]
+ isnum = False:False:repeat True
+ in unlines . map ((:) ' ' . intercalate " ") $
+ formatTable (header:map Node.list snl) isnum
+
+-- | Print the instance list.
+printInsts :: Node.List -> Instance.List -> String
+printInsts nl il =
+ let sil = sortBy (compare `on` Instance.idx) (Container.elems il)
+ helper inst = [ (Instance.name inst)
+ , (Container.nameOf nl (Instance.pNode inst))
+ , (let sdx = Instance.sNode inst
+ in if sdx == Node.noSecondary
+ then ""
+ else Container.nameOf nl sdx) ]
+ header = ["Name", "Pri_node", "Sec_node"]
+ isnum = repeat False
+ in unlines . map ((:) ' ' . intercalate " ") $
+ formatTable (header:map helper sil) isnum
+
+-- | Shows statistics for a given node list.
+printStats :: Node.List -> String
printStats nl =
- let (mem_cv, dsk_cv, n1_score, res_cv, off_score) = compDetailedCV nl
- in printf "f_mem=%.8f, r_mem=%.8f, f_dsk=%.8f, n1=%.3f, uf=%.3f"
- mem_cv res_cv dsk_cv n1_score off_score
+ let dcvs = compDetailedCV nl
+ hd = zip (detailedCVNames ++ repeat "unknown") dcvs
+ formatted = map (\(header, val) ->
+ printf "%s=%.8f" header val::String) hd
+ in intercalate ", " formatted
+
+-- | Convert a placement into a list of OpCodes (basically a job).
+iMoveToJob :: String -> Node.List -> Instance.List
+ -> Idx -> IMove -> [OpCodes.OpCode]
+iMoveToJob csf nl il idx move =
+ let inst = Container.find idx il
+ iname = Instance.name inst ++ csf
+ lookNode n = Just (Container.nameOf nl n ++ csf)
+ opF = if Instance.running inst
+ then OpCodes.OpMigrateInstance iname True False
+ else OpCodes.OpFailoverInstance iname False
+ opR n = OpCodes.OpReplaceDisks iname (lookNode n)
+ OpCodes.ReplaceNewSecondary [] Nothing
+ in case move of
+ Failover -> [ opF ]
+ ReplacePrimary np -> [ opF, opR np, opF ]
+ ReplaceSecondary ns -> [ opR ns ]
+ ReplaceAndFailover np -> [ opR np, opF ]
+ FailoverAndReplace ns -> [ opF, opR ns ]
projects / ganeti-local / blobdiff