root / src / Node.hs @ 38f63ae6
History | View | Annotate | Download (7 kB)
1 |
{-| Module describing a node. |
---|---|
2 |
|
3 |
All updates are functional (copy-based) and return a new node with |
4 |
updated value. |
5 |
-} |
6 |
|
7 |
module Node |
8 |
( |
9 |
Node(failN1, idx, f_mem, f_dsk, p_mem, p_dsk, slist, plist) |
10 |
-- * Constructor |
11 |
, create |
12 |
-- ** Finalization after data loading |
13 |
, buildPeers |
14 |
, setIdx |
15 |
-- * Instance (re)location |
16 |
, removePri |
17 |
, removeSec |
18 |
, addPri |
19 |
, addSec |
20 |
, setPri |
21 |
, setSec |
22 |
-- * Formatting |
23 |
, list |
24 |
) where |
25 |
|
26 |
import Data.List |
27 |
import Text.Printf (printf) |
28 |
|
29 |
import qualified Container |
30 |
import qualified Instance |
31 |
import qualified PeerMap |
32 |
|
33 |
import Utils |
34 |
|
35 |
data Node = Node { t_mem :: Double -- ^ total memory (Mib) |
36 |
, f_mem :: Int -- ^ free memory (MiB) |
37 |
, t_dsk :: Double -- ^ total disk space (MiB) |
38 |
, f_dsk :: 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 |
43 |
-- mapping |
44 |
, failN1:: Bool -- ^ whether the node has failed n1 |
45 |
, maxRes :: Int -- ^ maximum memory needed for |
46 |
-- failover by primaries of this node |
47 |
, p_mem :: Double |
48 |
, p_dsk :: Double |
49 |
} deriving (Show) |
50 |
|
51 |
{- | Create a new node. |
52 |
|
53 |
The index and the peers maps are empty, and will be need to be update |
54 |
later via the 'setIdx' and 'buildPeers' functions. |
55 |
|
56 |
-} |
57 |
create :: String -> String -> String -> String -> Node |
58 |
create mem_t_init mem_f_init dsk_t_init dsk_f_init = |
59 |
let mem_t = read mem_t_init |
60 |
mem_f = read mem_f_init |
61 |
dsk_t = read dsk_t_init |
62 |
dsk_f = read dsk_f_init |
63 |
in |
64 |
Node |
65 |
{ |
66 |
t_mem = read mem_t_init, |
67 |
f_mem = read mem_f_init, |
68 |
t_dsk = read dsk_t_init, |
69 |
f_dsk = read dsk_f_init, |
70 |
plist = [], |
71 |
slist = [], |
72 |
failN1 = True, |
73 |
idx = -1, |
74 |
peers = PeerMap.empty, |
75 |
maxRes = 0, |
76 |
p_mem = (fromIntegral mem_f) / (fromIntegral mem_t), |
77 |
p_dsk = (fromIntegral dsk_f) / (fromIntegral dsk_t) |
78 |
} |
79 |
|
80 |
-- | Changes the index. |
81 |
-- This is used only during the building of the data structures. |
82 |
setIdx :: Node -> Int -> Node |
83 |
setIdx t i = t {idx = i} |
84 |
|
85 |
-- | Given the rmem, free memory and disk, computes the failn1 status. |
86 |
computeFailN1 :: Int -> Int -> Int -> Bool |
87 |
computeFailN1 new_rmem new_mem new_dsk = |
88 |
new_mem <= new_rmem || new_dsk <= 0 |
89 |
|
90 |
-- | Computes the maximum reserved memory for peers from a peer map. |
91 |
computeMaxRes :: PeerMap.PeerMap -> PeerMap.Elem |
92 |
computeMaxRes new_peers = PeerMap.maxElem new_peers |
93 |
|
94 |
-- | Builds the peer map for a given node. |
95 |
buildPeers :: Node -> Container.Container Instance.Instance -> Int -> Node |
96 |
buildPeers t il num_nodes = |
97 |
let mdata = map |
98 |
(\i_idx -> let inst = Container.find i_idx il |
99 |
in (Instance.pnode inst, Instance.mem inst)) |
100 |
(slist t) |
101 |
pmap = PeerMap.accumArray (+) 0 (0, num_nodes - 1) mdata |
102 |
new_rmem = computeMaxRes pmap |
103 |
new_failN1 = computeFailN1 new_rmem (f_mem t) (f_dsk t) |
104 |
in t {peers=pmap, failN1 = new_failN1, maxRes = new_rmem} |
105 |
|
106 |
-- | Removes a primary instance. |
107 |
removePri :: Node -> Instance.Instance -> Node |
108 |
removePri t inst = |
109 |
let iname = Instance.idx inst |
110 |
new_plist = delete iname (plist t) |
111 |
new_mem = f_mem t + Instance.mem inst |
112 |
new_dsk = f_dsk t + Instance.dsk inst |
113 |
new_mp = (fromIntegral new_mem) / (t_mem t) |
114 |
new_dp = (fromIntegral new_dsk) / (t_dsk t) |
115 |
new_failn1 = computeFailN1 (maxRes t) new_mem new_dsk |
116 |
in t {plist = new_plist, f_mem = new_mem, f_dsk = new_dsk, |
117 |
failN1 = new_failn1, p_mem = new_mp, p_dsk = new_dp} |
118 |
|
119 |
-- | Removes a secondary instance. |
120 |
removeSec :: Node -> Instance.Instance -> Node |
121 |
removeSec t inst = |
122 |
let iname = Instance.idx inst |
123 |
pnode = Instance.pnode inst |
124 |
new_slist = delete iname (slist t) |
125 |
new_dsk = f_dsk t + Instance.dsk inst |
126 |
old_peers = peers t |
127 |
old_peem = PeerMap.find pnode old_peers |
128 |
new_peem = old_peem - (Instance.mem inst) |
129 |
new_peers = PeerMap.add pnode new_peem old_peers |
130 |
old_rmem = maxRes t |
131 |
new_rmem = if old_peem < old_rmem then |
132 |
old_rmem |
133 |
else |
134 |
computeMaxRes new_peers |
135 |
new_failn1 = computeFailN1 new_rmem (f_mem t) new_dsk |
136 |
new_dp = (fromIntegral new_dsk) / (t_dsk t) |
137 |
in t {slist = new_slist, f_dsk = new_dsk, peers = new_peers, |
138 |
failN1 = new_failn1, maxRes = new_rmem, p_dsk = new_dp} |
139 |
|
140 |
-- | Adds a primary instance. |
141 |
addPri :: Node -> Instance.Instance -> Maybe Node |
142 |
addPri t inst = |
143 |
let iname = Instance.idx inst |
144 |
new_mem = f_mem t - Instance.mem inst |
145 |
new_dsk = f_dsk t - Instance.dsk inst |
146 |
new_failn1 = computeFailN1 (maxRes t) new_mem new_dsk in |
147 |
if new_failn1 then |
148 |
Nothing |
149 |
else |
150 |
let new_plist = iname:(plist t) |
151 |
new_mp = (fromIntegral new_mem) / (t_mem t) |
152 |
new_dp = (fromIntegral new_dsk) / (t_dsk t) |
153 |
in |
154 |
Just t {plist = new_plist, f_mem = new_mem, f_dsk = new_dsk, |
155 |
failN1 = new_failn1, p_mem = new_mp, p_dsk = new_dp} |
156 |
|
157 |
-- | Adds a secondary instance. |
158 |
addSec :: Node -> Instance.Instance -> Int -> Maybe Node |
159 |
addSec t inst pdx = |
160 |
let iname = Instance.idx inst |
161 |
old_peers = peers t |
162 |
new_dsk = f_dsk t - Instance.dsk inst |
163 |
new_peem = PeerMap.find pdx old_peers + Instance.mem inst |
164 |
new_peers = PeerMap.add pdx new_peem old_peers |
165 |
new_rmem = max (maxRes t) new_peem |
166 |
new_failn1 = computeFailN1 new_rmem (f_mem t) new_dsk in |
167 |
if new_failn1 then |
168 |
Nothing |
169 |
else |
170 |
let new_slist = iname:(slist t) |
171 |
new_dp = (fromIntegral new_dsk) / (t_dsk t) |
172 |
in |
173 |
Just t {slist = new_slist, f_dsk = new_dsk, |
174 |
peers = new_peers, failN1 = new_failn1, |
175 |
maxRes = new_rmem, p_dsk = new_dp} |
176 |
|
177 |
-- | Add a primary instance to a node without other updates |
178 |
setPri :: Node -> Int -> Node |
179 |
setPri t idx = t { plist = idx:(plist t) } |
180 |
|
181 |
-- | Add a secondary instance to a node without other updates |
182 |
setSec :: Node -> Int -> Node |
183 |
setSec t idx = t { slist = idx:(slist t) } |
184 |
|
185 |
-- | Simple converter to string. |
186 |
str :: Node -> String |
187 |
str t = |
188 |
printf ("Node %d (mem=%5d MiB, disk=%5.2f GiB)\n Primaries:" ++ |
189 |
" %s\nSecondaries: %s") |
190 |
(idx t) (f_mem t) ((f_dsk t) `div` 1024) |
191 |
(commaJoin (map show (plist t))) |
192 |
(commaJoin (map show (slist t))) |
193 |
|
194 |
-- | String converter for the node list functionality. |
195 |
list :: String -> Node -> String |
196 |
list n t = |
197 |
let pl = plist t |
198 |
sl = slist t |
199 |
mp = p_mem t |
200 |
dp = p_dsk t |
201 |
in |
202 |
printf " %s(%d)\t%5d\t%5d\t%3d\t%3d\t%s\t%s\t%.5f\t%.5f" |
203 |
n (idx t) (f_mem t) ((f_dsk t) `div` 1024) |
204 |
(length pl) (length sl) |
205 |
(commaJoin (map show pl)) |
206 |
(commaJoin (map show sl)) |
207 |
mp dp |