1 {-| Module describing a node.
3 All updates are functional (copy-based) and return a new node with
9 Node(failN1, idx, f_mem, f_disk, slist, plist)
12 -- ** Finalization after data loading
15 -- * Instance (re)location
27 import Text.Printf (printf)
29 import qualified Container
30 import qualified Instance
31 import qualified PeerMap
35 data Node = Node { t_mem :: Int -- ^ total memory (Mib)
36 , f_mem :: Int -- ^ free memory (MiB)
37 , t_disk :: Int -- ^ total disk space (MiB)
38 , f_disk :: Int -- ^ free disk space (MiB)
39 , plist :: [Int] -- ^ list of primary instance indices
40 , slist :: [Int] -- ^ list of secondary instance indices
41 , idx :: Int -- ^ internal index for book-keeping
42 , peers:: PeerMap.PeerMap -- ^ primary node to instance
44 , failN1:: Bool -- ^ whether the node has failed n1
45 , maxRes :: Int -- ^ maximum memory needed for
46 -- failover by primaries of this node
49 {- | Create a new node.
51 The index and the peers maps are empty, and will be need to be update
52 later via the 'setIdx' and 'buildPeers' functions.
55 create :: String -> String -> String -> String -> [Int] -> [Int] -> Node
56 create mem_t_init mem_f_init disk_t_init disk_f_init
57 plist_init slist_init = Node
59 t_mem = read mem_t_init,
60 f_mem = read mem_f_init,
61 t_disk = read disk_t_init,
62 f_disk = read disk_f_init,
67 peers = PeerMap.empty,
71 -- | Changes the index.
72 -- This is used only during the building of the data structures.
73 setIdx :: Node -> Int -> Node
74 setIdx t i = t {idx = i}
76 -- | Given the rmem, free memory and disk, computes the failn1 status.
77 computeFailN1 :: Int -> Int -> Int -> Bool
78 computeFailN1 new_rmem new_mem new_disk =
79 new_mem <= new_rmem || new_disk <= 0
82 -- | Computes the maximum reserved memory for peers from a peer map.
83 computeMaxRes :: PeerMap.PeerMap -> PeerMap.Elem
84 computeMaxRes new_peers = PeerMap.maxElem new_peers
86 -- | Builds the peer map for a given node.
87 buildPeers :: Node -> Container.Container Instance.Instance -> Int -> Node
88 buildPeers t il num_nodes =
90 (\i_idx -> let inst = Container.find i_idx il
91 in (Instance.pnode inst, Instance.mem inst))
93 pmap = PeerMap.accumArray (+) 0 (0, num_nodes - 1) mdata
94 new_rmem = computeMaxRes pmap
95 new_failN1 = computeFailN1 new_rmem (f_mem t) (f_disk t)
96 in t {peers=pmap, failN1 = new_failN1, maxRes = new_rmem}
98 -- | Removes a primary instance.
99 removePri :: Node -> Instance.Instance -> Node
101 let iname = Instance.idx inst
102 new_plist = delete iname (plist t)
103 new_mem = f_mem t + Instance.mem inst
104 new_disk = f_disk t + Instance.disk inst
105 new_failn1 = computeFailN1 (maxRes t) new_mem new_disk
106 in t {plist = new_plist, f_mem = new_mem, f_disk = new_disk,
109 -- | Removes a secondary instance.
110 removeSec :: Node -> Instance.Instance -> Node
112 let iname = Instance.idx inst
113 pnode = Instance.pnode inst
114 new_slist = delete iname (slist t)
115 new_disk = f_disk t + Instance.disk inst
117 old_peem = PeerMap.find pnode old_peers
118 new_peem = old_peem - (Instance.mem inst)
119 new_peers = PeerMap.add pnode new_peem old_peers
121 new_rmem = if old_peem < old_rmem then
124 computeMaxRes new_peers
125 new_failn1 = computeFailN1 new_rmem (f_mem t) new_disk
126 in t {slist = new_slist, f_disk = new_disk, peers = new_peers,
127 failN1 = new_failn1, maxRes = new_rmem}
129 -- | Adds a primary instance.
130 addPri :: Node -> Instance.Instance -> Maybe Node
132 let iname = Instance.idx inst
133 new_mem = f_mem t - Instance.mem inst
134 new_disk = f_disk t - Instance.disk inst
135 new_failn1 = computeFailN1 (maxRes t) new_mem new_disk in
139 let new_plist = iname:(plist t) in
140 Just t {plist = new_plist, f_mem = new_mem, f_disk = new_disk,
143 -- | Adds a secondary instance.
144 addSec :: Node -> Instance.Instance -> Int -> Maybe Node
146 let iname = Instance.idx inst
148 new_disk = f_disk t - Instance.disk inst
149 new_peem = PeerMap.find pdx old_peers + Instance.mem inst
150 new_peers = PeerMap.add pdx new_peem old_peers
151 new_rmem = max (maxRes t) new_peem
152 new_failn1 = computeFailN1 new_rmem (f_mem t) new_disk in
156 let new_slist = iname:(slist t) in
157 Just t {slist = new_slist, f_disk = new_disk,
158 peers = new_peers, failN1 = new_failn1,
161 -- | Simple converter to string.
162 str :: Node -> String
164 printf ("Node %d (mem=%5d MiB, disk=%5.2f GiB)\n Primaries:" ++
165 " %s\nSecondaries: %s")
166 (idx t) (f_mem t) ((f_disk t) `div` 1024)
167 (commaJoin (map show (plist t)))
168 (commaJoin (map show (slist t)))
170 -- | String converter for the node list functionality.
171 list :: String -> Node -> String
175 (mp, dp) = normUsed t
177 printf " %s(%d)\t%5d\t%5d\t%3d\t%3d\t%s\t%s\t%.5f\t%.5f"
178 n (idx t) (f_mem t) ((f_disk t) `div` 1024)
179 (length pl) (length sl)
180 (commaJoin (map show pl))
181 (commaJoin (map show sl))
184 -- | Normalize the usage status
185 -- This converts the used memory and disk values into a normalized integer
186 -- value, currently expresed as per mille of totals
188 normUsed :: Node -> (Double, Double)
190 let mp = (fromIntegral $ f_mem n) / (fromIntegral $ t_mem n)
191 dp = (fromIntegral $ f_disk n) / (fromIntegral $ t_disk n)