root / htools / Ganeti / HTools / Types.hs @ 5f828ce4
History | View | Annotate | Download (8.9 kB)
1 |
{-# LANGUAGE TemplateHaskell #-} |
---|---|
2 |
|
3 |
{-| Some common types. |
4 |
|
5 |
-} |
6 |
|
7 |
{- |
8 |
|
9 |
Copyright (C) 2009, 2010, 2011 Google Inc. |
10 |
|
11 |
This program is free software; you can redistribute it and/or modify |
12 |
it under the terms of the GNU General Public License as published by |
13 |
the Free Software Foundation; either version 2 of the License, or |
14 |
(at your option) any later version. |
15 |
|
16 |
This program is distributed in the hope that it will be useful, but |
17 |
WITHOUT ANY WARRANTY; without even the implied warranty of |
18 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
19 |
General Public License for more details. |
20 |
|
21 |
You should have received a copy of the GNU General Public License |
22 |
along with this program; if not, write to the Free Software |
23 |
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
24 |
02110-1301, USA. |
25 |
|
26 |
-} |
27 |
|
28 |
module Ganeti.HTools.Types |
29 |
( Idx |
30 |
, Ndx |
31 |
, Gdx |
32 |
, NameAssoc |
33 |
, Score |
34 |
, Weight |
35 |
, GroupID |
36 |
, AllocPolicy(..) |
37 |
, allocPolicyFromRaw |
38 |
, allocPolicyToRaw |
39 |
, RSpec(..) |
40 |
, DynUtil(..) |
41 |
, zeroUtil |
42 |
, baseUtil |
43 |
, addUtil |
44 |
, subUtil |
45 |
, defVcpuRatio |
46 |
, defReservedDiskRatio |
47 |
, unitMem |
48 |
, unitCpu |
49 |
, unitDsk |
50 |
, unknownField |
51 |
, Placement |
52 |
, IMove(..) |
53 |
, DiskTemplate(..) |
54 |
, diskTemplateToRaw |
55 |
, diskTemplateFromRaw |
56 |
, MoveJob |
57 |
, JobSet |
58 |
, Result(..) |
59 |
, isOk |
60 |
, isBad |
61 |
, eitherToResult |
62 |
, Element(..) |
63 |
, FailMode(..) |
64 |
, FailStats |
65 |
, OpResult(..) |
66 |
, opToResult |
67 |
, connTimeout |
68 |
, queryTimeout |
69 |
, EvacMode(..) |
70 |
) where |
71 |
|
72 |
import Control.Monad |
73 |
import qualified Data.Map as M |
74 |
import qualified Text.JSON as JSON |
75 |
|
76 |
import qualified Ganeti.Constants as C |
77 |
import qualified Ganeti.THH as THH |
78 |
|
79 |
-- | The instance index type. |
80 |
type Idx = Int |
81 |
|
82 |
-- | The node index type. |
83 |
type Ndx = Int |
84 |
|
85 |
-- | The group index type. |
86 |
type Gdx = Int |
87 |
|
88 |
-- | The type used to hold name-to-idx mappings. |
89 |
type NameAssoc = M.Map String Int |
90 |
|
91 |
-- | A separate name for the cluster score type. |
92 |
type Score = Double |
93 |
|
94 |
-- | A separate name for a weight metric. |
95 |
type Weight = Double |
96 |
|
97 |
-- | The Group UUID type. |
98 |
type GroupID = String |
99 |
|
100 |
-- | The Group allocation policy type. |
101 |
-- |
102 |
-- Note that the order of constructors is important as the automatic |
103 |
-- Ord instance will order them in the order they are defined, so when |
104 |
-- changing this data type be careful about the interaction with the |
105 |
-- desired sorting order. |
106 |
$(THH.declareSADT "AllocPolicy" |
107 |
[ ("AllocPreferred", 'C.allocPolicyPreferred) |
108 |
, ("AllocLastResort", 'C.allocPolicyLastResort) |
109 |
, ("AllocUnallocable", 'C.allocPolicyUnallocable) |
110 |
]) |
111 |
$(THH.makeJSONInstance ''AllocPolicy) |
112 |
|
113 |
-- | The resource spec type. |
114 |
data RSpec = RSpec |
115 |
{ rspecCpu :: Int -- ^ Requested VCPUs |
116 |
, rspecMem :: Int -- ^ Requested memory |
117 |
, rspecDsk :: Int -- ^ Requested disk |
118 |
} deriving (Show, Read, Eq) |
119 |
|
120 |
-- | The dynamic resource specs of a machine (i.e. load or load |
121 |
-- capacity, as opposed to size). |
122 |
data DynUtil = DynUtil |
123 |
{ cpuWeight :: Weight -- ^ Standardised CPU usage |
124 |
, memWeight :: Weight -- ^ Standardised memory load |
125 |
, dskWeight :: Weight -- ^ Standardised disk I\/O usage |
126 |
, netWeight :: Weight -- ^ Standardised network usage |
127 |
} deriving (Show, Read, Eq) |
128 |
|
129 |
-- | Initial empty utilisation. |
130 |
zeroUtil :: DynUtil |
131 |
zeroUtil = DynUtil { cpuWeight = 0, memWeight = 0 |
132 |
, dskWeight = 0, netWeight = 0 } |
133 |
|
134 |
-- | Base utilisation (used when no actual utilisation data is |
135 |
-- supplied). |
136 |
baseUtil :: DynUtil |
137 |
baseUtil = DynUtil { cpuWeight = 1, memWeight = 1 |
138 |
, dskWeight = 1, netWeight = 1 } |
139 |
|
140 |
-- | Sum two utilisation records. |
141 |
addUtil :: DynUtil -> DynUtil -> DynUtil |
142 |
addUtil (DynUtil a1 a2 a3 a4) (DynUtil b1 b2 b3 b4) = |
143 |
DynUtil (a1+b1) (a2+b2) (a3+b3) (a4+b4) |
144 |
|
145 |
-- | Substracts one utilisation record from another. |
146 |
subUtil :: DynUtil -> DynUtil -> DynUtil |
147 |
subUtil (DynUtil a1 a2 a3 a4) (DynUtil b1 b2 b3 b4) = |
148 |
DynUtil (a1-b1) (a2-b2) (a3-b3) (a4-b4) |
149 |
|
150 |
-- | The description of an instance placement. It contains the |
151 |
-- instance index, the new primary and secondary node, the move being |
152 |
-- performed and the score of the cluster after the move. |
153 |
type Placement = (Idx, Ndx, Ndx, IMove, Score) |
154 |
|
155 |
-- | An instance move definition. |
156 |
data IMove = Failover -- ^ Failover the instance (f) |
157 |
| ReplacePrimary Ndx -- ^ Replace primary (f, r:np, f) |
158 |
| ReplaceSecondary Ndx -- ^ Replace secondary (r:ns) |
159 |
| ReplaceAndFailover Ndx -- ^ Replace secondary, failover (r:np, f) |
160 |
| FailoverAndReplace Ndx -- ^ Failover, replace secondary (f, r:ns) |
161 |
deriving (Show, Read) |
162 |
|
163 |
-- | Instance disk template type. |
164 |
$(THH.declareSADT "DiskTemplate" |
165 |
[ ("DTDiskless", 'C.dtDiskless) |
166 |
, ("DTFile", 'C.dtFile) |
167 |
, ("DTSharedFile", 'C.dtSharedFile) |
168 |
, ("DTPlain", 'C.dtPlain) |
169 |
, ("DTBlock", 'C.dtBlock) |
170 |
, ("DTDrbd8", 'C.dtDrbd8) |
171 |
]) |
172 |
$(THH.makeJSONInstance ''DiskTemplate) |
173 |
|
174 |
-- | Formatted solution output for one move (involved nodes and |
175 |
-- commands. |
176 |
type MoveJob = ([Ndx], Idx, IMove, [String]) |
177 |
|
178 |
-- | Unknown field in table output. |
179 |
unknownField :: String |
180 |
unknownField = "<unknown field>" |
181 |
|
182 |
-- | A list of command elements. |
183 |
type JobSet = [MoveJob] |
184 |
|
185 |
-- | Connection timeout (when using non-file methods). |
186 |
connTimeout :: Int |
187 |
connTimeout = 15 |
188 |
|
189 |
-- | The default timeout for queries (when using non-file methods). |
190 |
queryTimeout :: Int |
191 |
queryTimeout = 60 |
192 |
|
193 |
-- | Default vcpu-to-pcpu ratio (randomly chosen value). |
194 |
defVcpuRatio :: Double |
195 |
defVcpuRatio = 64 |
196 |
|
197 |
-- | Default max disk usage ratio. |
198 |
defReservedDiskRatio :: Double |
199 |
defReservedDiskRatio = 0 |
200 |
|
201 |
-- | Base memory unit. |
202 |
unitMem :: Int |
203 |
unitMem = 64 |
204 |
|
205 |
-- | Base disk unit. |
206 |
unitDsk :: Int |
207 |
unitDsk = 256 |
208 |
|
209 |
-- | Base vcpus unit. |
210 |
unitCpu :: Int |
211 |
unitCpu = 1 |
212 |
|
213 |
-- | This is similar to the JSON library Result type - /very/ similar, |
214 |
-- but we want to use it in multiple places, so we abstract it into a |
215 |
-- mini-library here. |
216 |
-- |
217 |
-- The failure value for this monad is simply a string. |
218 |
data Result a |
219 |
= Bad String |
220 |
| Ok a |
221 |
deriving (Show, Read, Eq) |
222 |
|
223 |
instance Monad Result where |
224 |
(>>=) (Bad x) _ = Bad x |
225 |
(>>=) (Ok x) fn = fn x |
226 |
return = Ok |
227 |
fail = Bad |
228 |
|
229 |
instance MonadPlus Result where |
230 |
mzero = Bad "zero Result when used as MonadPlus" |
231 |
-- for mplus, when we 'add' two Bad values, we concatenate their |
232 |
-- error descriptions |
233 |
(Bad x) `mplus` (Bad y) = Bad (x ++ "; " ++ y) |
234 |
(Bad _) `mplus` x = x |
235 |
x@(Ok _) `mplus` _ = x |
236 |
|
237 |
-- | Simple checker for whether a 'Result' is OK. |
238 |
isOk :: Result a -> Bool |
239 |
isOk (Ok _) = True |
240 |
isOk _ = False |
241 |
|
242 |
-- | Simple checker for whether a 'Result' is a failure. |
243 |
isBad :: Result a -> Bool |
244 |
isBad = not . isOk |
245 |
|
246 |
-- | Converter from Either String to 'Result'. |
247 |
eitherToResult :: Either String a -> Result a |
248 |
eitherToResult (Left s) = Bad s |
249 |
eitherToResult (Right v) = Ok v |
250 |
|
251 |
-- | Reason for an operation's falure. |
252 |
data FailMode = FailMem -- ^ Failed due to not enough RAM |
253 |
| FailDisk -- ^ Failed due to not enough disk |
254 |
| FailCPU -- ^ Failed due to not enough CPU capacity |
255 |
| FailN1 -- ^ Failed due to not passing N1 checks |
256 |
| FailTags -- ^ Failed due to tag exclusion |
257 |
deriving (Eq, Enum, Bounded, Show, Read) |
258 |
|
259 |
-- | List with failure statistics. |
260 |
type FailStats = [(FailMode, Int)] |
261 |
|
262 |
-- | Either-like data-type customized for our failure modes. |
263 |
-- |
264 |
-- The failure values for this monad track the specific allocation |
265 |
-- failures, so this is not a general error-monad (compare with the |
266 |
-- 'Result' data type). One downside is that this type cannot encode a |
267 |
-- generic failure mode, hence 'fail' for this monad is not defined |
268 |
-- and will cause an exception. |
269 |
data OpResult a = OpFail FailMode -- ^ Failed operation |
270 |
| OpGood a -- ^ Success operation |
271 |
deriving (Show, Read) |
272 |
|
273 |
instance Monad OpResult where |
274 |
(OpGood x) >>= fn = fn x |
275 |
(OpFail y) >>= _ = OpFail y |
276 |
return = OpGood |
277 |
|
278 |
-- | Conversion from 'OpResult' to 'Result'. |
279 |
opToResult :: OpResult a -> Result a |
280 |
opToResult (OpFail f) = Bad $ show f |
281 |
opToResult (OpGood v) = Ok v |
282 |
|
283 |
-- | A generic class for items that have updateable names and indices. |
284 |
class Element a where |
285 |
-- | Returns the name of the element |
286 |
nameOf :: a -> String |
287 |
-- | Returns all the known names of the element |
288 |
allNames :: a -> [String] |
289 |
-- | Returns the index of the element |
290 |
idxOf :: a -> Int |
291 |
-- | Updates the alias of the element |
292 |
setAlias :: a -> String -> a |
293 |
-- | Compute the alias by stripping a given suffix (domain) from |
294 |
-- the name |
295 |
computeAlias :: String -> a -> a |
296 |
computeAlias dom e = setAlias e alias |
297 |
where alias = take (length name - length dom) name |
298 |
name = nameOf e |
299 |
-- | Updates the index of the element |
300 |
setIdx :: a -> Int -> a |
301 |
|
302 |
-- | The iallocator node-evacuate evac_mode type. |
303 |
$(THH.declareSADT "EvacMode" |
304 |
[ ("ChangePrimary", 'C.iallocatorNevacPri) |
305 |
, ("ChangeSecondary", 'C.iallocatorNevacSec) |
306 |
, ("ChangeAll", 'C.iallocatorNevacAll) |
307 |
]) |
308 |
$(THH.makeJSONInstance ''EvacMode) |