root / htools / Ganeti / HTools / Program / Hbal.hs @ 2a2e2610
History | View | Annotate | Download (14.8 kB)
1 |
{-| Cluster rebalancer. |
---|---|
2 |
|
3 |
-} |
4 |
|
5 |
{- |
6 |
|
7 |
Copyright (C) 2009, 2010, 2011, 2012 Google Inc. |
8 |
|
9 |
This program is free software; you can redistribute it and/or modify |
10 |
it under the terms of the GNU General Public License as published by |
11 |
the Free Software Foundation; either version 2 of the License, or |
12 |
(at your option) any later version. |
13 |
|
14 |
This program is distributed in the hope that it will be useful, but |
15 |
WITHOUT ANY WARRANTY; without even the implied warranty of |
16 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
17 |
General Public License for more details. |
18 |
|
19 |
You should have received a copy of the GNU General Public License |
20 |
along with this program; if not, write to the Free Software |
21 |
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
22 |
02110-1301, USA. |
23 |
|
24 |
-} |
25 |
|
26 |
module Ganeti.HTools.Program.Hbal (main, options) where |
27 |
|
28 |
import Control.Concurrent (threadDelay) |
29 |
import Control.Exception (bracket) |
30 |
import Control.Monad |
31 |
import Data.List |
32 |
import Data.Maybe (isJust, isNothing, fromJust) |
33 |
import Data.IORef |
34 |
import System.Exit |
35 |
import System.IO |
36 |
import System.Posix.Process |
37 |
import System.Posix.Signals |
38 |
|
39 |
import Text.Printf (printf, hPrintf) |
40 |
|
41 |
import qualified Ganeti.HTools.Container as Container |
42 |
import qualified Ganeti.HTools.Cluster as Cluster |
43 |
import qualified Ganeti.HTools.Group as Group |
44 |
import qualified Ganeti.HTools.Node as Node |
45 |
import qualified Ganeti.HTools.Instance as Instance |
46 |
|
47 |
import Ganeti.HTools.CLI |
48 |
import Ganeti.HTools.ExtLoader |
49 |
import Ganeti.HTools.Utils |
50 |
import Ganeti.HTools.Types |
51 |
import Ganeti.HTools.Loader |
52 |
|
53 |
import qualified Ganeti.Luxi as L |
54 |
import Ganeti.Jobs |
55 |
|
56 |
-- | Options list and functions. |
57 |
options :: [OptType] |
58 |
options = |
59 |
[ oPrintNodes |
60 |
, oPrintInsts |
61 |
, oPrintCommands |
62 |
, oDataFile |
63 |
, oEvacMode |
64 |
, oRapiMaster |
65 |
, oLuxiSocket |
66 |
, oIAllocSrc |
67 |
, oExecJobs |
68 |
, oGroup |
69 |
, oMaxSolLength |
70 |
, oVerbose |
71 |
, oQuiet |
72 |
, oOfflineNode |
73 |
, oMinScore |
74 |
, oMaxCpu |
75 |
, oMinDisk |
76 |
, oMinGain |
77 |
, oMinGainLim |
78 |
, oDiskMoves |
79 |
, oSelInst |
80 |
, oInstMoves |
81 |
, oDynuFile |
82 |
, oExTags |
83 |
, oExInst |
84 |
, oSaveCluster |
85 |
, oShowVer |
86 |
, oShowHelp |
87 |
] |
88 |
|
89 |
{- | Start computing the solution at the given depth and recurse until |
90 |
we find a valid solution or we exceed the maximum depth. |
91 |
|
92 |
-} |
93 |
iterateDepth :: Cluster.Table -- ^ The starting table |
94 |
-> Int -- ^ Remaining length |
95 |
-> Bool -- ^ Allow disk moves |
96 |
-> Bool -- ^ Allow instance moves |
97 |
-> Int -- ^ Max node name len |
98 |
-> Int -- ^ Max instance name len |
99 |
-> [MoveJob] -- ^ Current command list |
100 |
-> Score -- ^ Score at which to stop |
101 |
-> Score -- ^ Min gain limit |
102 |
-> Score -- ^ Min score gain |
103 |
-> Bool -- ^ Enable evacuation mode |
104 |
-> IO (Cluster.Table, [MoveJob]) -- ^ The resulting table |
105 |
-- and commands |
106 |
iterateDepth ini_tbl max_rounds disk_moves inst_moves nmlen imlen |
107 |
cmd_strs min_score mg_limit min_gain evac_mode = |
108 |
let Cluster.Table ini_nl ini_il _ _ = ini_tbl |
109 |
allowed_next = Cluster.doNextBalance ini_tbl max_rounds min_score |
110 |
m_fin_tbl = if allowed_next |
111 |
then Cluster.tryBalance ini_tbl disk_moves inst_moves |
112 |
evac_mode mg_limit min_gain |
113 |
else Nothing |
114 |
in case m_fin_tbl of |
115 |
Just fin_tbl -> |
116 |
do |
117 |
let (Cluster.Table _ _ _ fin_plc) = fin_tbl |
118 |
fin_plc_len = length fin_plc |
119 |
cur_plc@(idx, _, _, move, _) = head fin_plc |
120 |
(sol_line, cmds) = Cluster.printSolutionLine ini_nl ini_il |
121 |
nmlen imlen cur_plc fin_plc_len |
122 |
afn = Cluster.involvedNodes ini_il cur_plc |
123 |
upd_cmd_strs = (afn, idx, move, cmds):cmd_strs |
124 |
putStrLn sol_line |
125 |
hFlush stdout |
126 |
iterateDepth fin_tbl max_rounds disk_moves inst_moves |
127 |
nmlen imlen upd_cmd_strs min_score |
128 |
mg_limit min_gain evac_mode |
129 |
Nothing -> return (ini_tbl, cmd_strs) |
130 |
|
131 |
-- | Displays the cluster stats. |
132 |
printStats :: Node.List -> Node.List -> IO () |
133 |
printStats ini_nl fin_nl = do |
134 |
let ini_cs = Cluster.totalResources ini_nl |
135 |
fin_cs = Cluster.totalResources fin_nl |
136 |
printf "Original: mem=%d disk=%d\n" |
137 |
(Cluster.csFmem ini_cs) (Cluster.csFdsk ini_cs) :: IO () |
138 |
printf "Final: mem=%d disk=%d\n" |
139 |
(Cluster.csFmem fin_cs) (Cluster.csFdsk fin_cs) |
140 |
|
141 |
-- | Saves the rebalance commands to a text file. |
142 |
saveBalanceCommands :: Options -> String -> IO () |
143 |
saveBalanceCommands opts cmd_data = do |
144 |
let out_path = fromJust $ optShowCmds opts |
145 |
putStrLn "" |
146 |
if out_path == "-" |
147 |
then printf "Commands to run to reach the above solution:\n%s" |
148 |
(unlines . map (" " ++) . |
149 |
filter (/= " check") . |
150 |
lines $ cmd_data) |
151 |
else do |
152 |
writeFile out_path (shTemplate ++ cmd_data) |
153 |
printf "The commands have been written to file '%s'\n" out_path |
154 |
|
155 |
-- | Polls a set of jobs at a fixed interval until all are finished |
156 |
-- one way or another. |
157 |
waitForJobs :: L.Client -> [String] -> IO (Result [JobStatus]) |
158 |
waitForJobs client jids = do |
159 |
sts <- L.queryJobsStatus client jids |
160 |
case sts of |
161 |
Bad x -> return $ Bad x |
162 |
Ok s -> if any (<= JOB_STATUS_RUNNING) s |
163 |
then do |
164 |
-- TODO: replace hardcoded value with a better thing |
165 |
threadDelay (1000000 * 15) |
166 |
waitForJobs client jids |
167 |
else return $ Ok s |
168 |
|
169 |
-- | Check that a set of job statuses is all success. |
170 |
checkJobsStatus :: [JobStatus] -> Bool |
171 |
checkJobsStatus = all (== JOB_STATUS_SUCCESS) |
172 |
|
173 |
-- | Wrapper over execJobSet checking for early termination. |
174 |
execWrapper :: String -> Node.List |
175 |
-> Instance.List -> IORef Int -> [JobSet] -> IO Bool |
176 |
execWrapper _ _ _ _ [] = return True |
177 |
execWrapper master nl il cref alljss = do |
178 |
cancel <- readIORef cref |
179 |
if cancel > 0 |
180 |
then do |
181 |
hPrintf stderr "Exiting early due to user request, %d\ |
182 |
\ jobset(s) remaining." (length alljss)::IO () |
183 |
return True |
184 |
else execJobSet master nl il cref alljss |
185 |
|
186 |
-- | Execute an entire jobset. |
187 |
execJobSet :: String -> Node.List |
188 |
-> Instance.List -> IORef Int -> [JobSet] -> IO Bool |
189 |
execJobSet _ _ _ _ [] = return True |
190 |
execJobSet master nl il cref (js:jss) = do |
191 |
-- map from jobset (htools list of positions) to [[opcodes]] |
192 |
let jobs = map (\(_, idx, move, _) -> |
193 |
Cluster.iMoveToJob nl il idx move) js |
194 |
let descr = map (\(_, idx, _, _) -> Container.nameOf il idx) js |
195 |
putStrLn $ "Executing jobset for instances " ++ commaJoin descr |
196 |
jrs <- bracket (L.getClient master) L.closeClient |
197 |
(\client -> do |
198 |
jids <- L.submitManyJobs client jobs |
199 |
case jids of |
200 |
Bad x -> return $ Bad x |
201 |
Ok x -> do |
202 |
putStrLn $ "Got job IDs " ++ commaJoin x |
203 |
waitForJobs client x |
204 |
) |
205 |
case jrs of |
206 |
Bad x -> do |
207 |
hPutStrLn stderr $ "Cannot compute job status, aborting: " ++ show x |
208 |
return False |
209 |
Ok x -> if checkJobsStatus x |
210 |
then execWrapper master nl il cref jss |
211 |
else do |
212 |
hPutStrLn stderr $ "Not all jobs completed successfully: " ++ |
213 |
show x |
214 |
hPutStrLn stderr "Aborting." |
215 |
return False |
216 |
|
217 |
-- | Executes the jobs, if possible and desired. |
218 |
maybeExecJobs :: Options |
219 |
-> [a] |
220 |
-> Node.List |
221 |
-> Instance.List |
222 |
-> [JobSet] |
223 |
-> IO Bool |
224 |
maybeExecJobs opts ord_plc fin_nl il cmd_jobs = |
225 |
if optExecJobs opts && not (null ord_plc) |
226 |
then (case optLuxi opts of |
227 |
Nothing -> do |
228 |
hPutStrLn stderr "Execution of commands possible only on LUXI" |
229 |
return False |
230 |
Just master -> runJobSet master fin_nl il cmd_jobs) |
231 |
else return True |
232 |
|
233 |
-- | Signal handler for graceful termination. |
234 |
hangleSigInt :: IORef Int -> IO () |
235 |
hangleSigInt cref = do |
236 |
writeIORef cref 1 |
237 |
putStrLn ("Cancel request registered, will exit at" ++ |
238 |
" the end of the current job set...") |
239 |
|
240 |
-- | Signal handler for immediate termination. |
241 |
hangleSigTerm :: IORef Int -> IO () |
242 |
hangleSigTerm cref = do |
243 |
-- update the cref to 2, just for consistency |
244 |
writeIORef cref 2 |
245 |
putStrLn "Double cancel request, exiting now..." |
246 |
exitImmediately $ ExitFailure 2 |
247 |
|
248 |
-- | Runs a job set with handling of signals. |
249 |
runJobSet :: String -> Node.List -> Instance.List -> [JobSet] -> IO Bool |
250 |
runJobSet master fin_nl il cmd_jobs = do |
251 |
cref <- newIORef 0 |
252 |
mapM_ (\(hnd, sig) -> installHandler sig (Catch (hnd cref)) Nothing) |
253 |
[(hangleSigTerm, softwareTermination), (hangleSigInt, keyboardSignal)] |
254 |
execWrapper master fin_nl il cref cmd_jobs |
255 |
|
256 |
-- | Select the target node group. |
257 |
selectGroup :: Options -> Group.List -> Node.List -> Instance.List |
258 |
-> IO (String, (Node.List, Instance.List)) |
259 |
selectGroup opts gl nlf ilf = do |
260 |
let ngroups = Cluster.splitCluster nlf ilf |
261 |
when (length ngroups > 1 && isNothing (optGroup opts)) $ do |
262 |
hPutStrLn stderr "Found multiple node groups:" |
263 |
mapM_ (hPutStrLn stderr . (" " ++) . Group.name . |
264 |
flip Container.find gl . fst) ngroups |
265 |
hPutStrLn stderr "Aborting." |
266 |
exitWith $ ExitFailure 1 |
267 |
|
268 |
case optGroup opts of |
269 |
Nothing -> do |
270 |
let (gidx, cdata) = head ngroups |
271 |
grp = Container.find gidx gl |
272 |
return (Group.name grp, cdata) |
273 |
Just g -> case Container.findByName gl g of |
274 |
Nothing -> do |
275 |
hPutStrLn stderr $ "Node group " ++ g ++ |
276 |
" not found. Node group list is:" |
277 |
mapM_ (hPutStrLn stderr . (" " ++) . Group.name ) (Container.elems gl) |
278 |
hPutStrLn stderr "Aborting." |
279 |
exitWith $ ExitFailure 1 |
280 |
Just grp -> |
281 |
case lookup (Group.idx grp) ngroups of |
282 |
Nothing -> |
283 |
-- This will only happen if there are no nodes assigned |
284 |
-- to this group |
285 |
return (Group.name grp, (Container.empty, Container.empty)) |
286 |
Just cdata -> return (Group.name grp, cdata) |
287 |
|
288 |
-- | Do a few checks on the cluster data. |
289 |
checkCluster :: Int -> Node.List -> Instance.List -> IO () |
290 |
checkCluster verbose nl il = do |
291 |
-- nothing to do on an empty cluster |
292 |
when (Container.null il) $ do |
293 |
printf "Cluster is empty, exiting.\n"::IO () |
294 |
exitWith ExitSuccess |
295 |
|
296 |
-- hbal doesn't currently handle split clusters |
297 |
let split_insts = Cluster.findSplitInstances nl il |
298 |
unless (null split_insts) $ do |
299 |
hPutStrLn stderr "Found instances belonging to multiple node groups:" |
300 |
mapM_ (\i -> hPutStrLn stderr $ " " ++ Instance.name i) split_insts |
301 |
hPutStrLn stderr "Aborting." |
302 |
exitWith $ ExitFailure 1 |
303 |
|
304 |
printf "Loaded %d nodes, %d instances\n" |
305 |
(Container.size nl) |
306 |
(Container.size il)::IO () |
307 |
|
308 |
let csf = commonSuffix nl il |
309 |
when (not (null csf) && verbose > 1) $ |
310 |
printf "Note: Stripping common suffix of '%s' from names\n" csf |
311 |
|
312 |
-- | Do a few checks on the selected group data. |
313 |
checkGroup :: Int -> String -> Node.List -> Instance.List -> IO () |
314 |
checkGroup verbose gname nl il = do |
315 |
printf "Group size %d nodes, %d instances\n" |
316 |
(Container.size nl) |
317 |
(Container.size il)::IO () |
318 |
|
319 |
putStrLn $ "Selected node group: " ++ gname |
320 |
|
321 |
let (bad_nodes, bad_instances) = Cluster.computeBadItems nl il |
322 |
unless (verbose == 0) $ printf |
323 |
"Initial check done: %d bad nodes, %d bad instances.\n" |
324 |
(length bad_nodes) (length bad_instances) |
325 |
|
326 |
when (length bad_nodes > 0) $ |
327 |
putStrLn "Cluster is not N+1 happy, continuing but no guarantee \ |
328 |
\that the cluster will end N+1 happy." |
329 |
|
330 |
-- | Check that we actually need to rebalance. |
331 |
checkNeedRebalance :: Options -> Score -> IO () |
332 |
checkNeedRebalance opts ini_cv = do |
333 |
let min_cv = optMinScore opts |
334 |
when (ini_cv < min_cv) $ do |
335 |
printf "Cluster is already well balanced (initial score %.6g,\n\ |
336 |
\minimum score %.6g).\nNothing to do, exiting\n" |
337 |
ini_cv min_cv:: IO () |
338 |
exitWith ExitSuccess |
339 |
|
340 |
-- | Main function. |
341 |
main :: Options -> [String] -> IO () |
342 |
main opts args = do |
343 |
unless (null args) $ do |
344 |
hPutStrLn stderr "Error: this program doesn't take any arguments." |
345 |
exitWith $ ExitFailure 1 |
346 |
|
347 |
let verbose = optVerbose opts |
348 |
shownodes = optShowNodes opts |
349 |
showinsts = optShowInsts opts |
350 |
|
351 |
ini_cdata@(ClusterData gl fixed_nl ilf ctags ipol) <- loadExternalData opts |
352 |
|
353 |
when (verbose > 1) $ do |
354 |
putStrLn $ "Loaded cluster tags: " ++ intercalate "," ctags |
355 |
putStrLn $ "Loaded cluster ipolicy: " ++ show ipol |
356 |
|
357 |
nlf <- setNodeStatus opts fixed_nl |
358 |
checkCluster verbose nlf ilf |
359 |
|
360 |
maybeSaveData (optSaveCluster opts) "original" "before balancing" ini_cdata |
361 |
|
362 |
(gname, (nl, il)) <- selectGroup opts gl nlf ilf |
363 |
|
364 |
checkGroup verbose gname nl il |
365 |
|
366 |
maybePrintInsts showinsts "Initial" (Cluster.printInsts nl il) |
367 |
|
368 |
maybePrintNodes shownodes "Initial cluster" (Cluster.printNodes nl) |
369 |
|
370 |
let ini_cv = Cluster.compCV nl |
371 |
ini_tbl = Cluster.Table nl il ini_cv [] |
372 |
min_cv = optMinScore opts |
373 |
|
374 |
checkNeedRebalance opts ini_cv |
375 |
|
376 |
if verbose > 2 |
377 |
then printf "Initial coefficients: overall %.8f\n%s" |
378 |
ini_cv (Cluster.printStats " " nl)::IO () |
379 |
else printf "Initial score: %.8f\n" ini_cv |
380 |
|
381 |
putStrLn "Trying to minimize the CV..." |
382 |
let imlen = maximum . map (length . Instance.alias) $ Container.elems il |
383 |
nmlen = maximum . map (length . Node.alias) $ Container.elems nl |
384 |
|
385 |
(fin_tbl, cmd_strs) <- iterateDepth ini_tbl (optMaxLength opts) |
386 |
(optDiskMoves opts) |
387 |
(optInstMoves opts) |
388 |
nmlen imlen [] min_cv |
389 |
(optMinGainLim opts) (optMinGain opts) |
390 |
(optEvacMode opts) |
391 |
let (Cluster.Table fin_nl fin_il fin_cv fin_plc) = fin_tbl |
392 |
ord_plc = reverse fin_plc |
393 |
sol_msg = case () of |
394 |
_ | null fin_plc -> printf "No solution found\n" |
395 |
| verbose > 2 -> |
396 |
printf "Final coefficients: overall %.8f\n%s" |
397 |
fin_cv (Cluster.printStats " " fin_nl) |
398 |
| otherwise -> |
399 |
printf "Cluster score improved from %.8f to %.8f\n" |
400 |
ini_cv fin_cv ::String |
401 |
|
402 |
putStr sol_msg |
403 |
|
404 |
unless (verbose == 0) $ |
405 |
printf "Solution length=%d\n" (length ord_plc) |
406 |
|
407 |
let cmd_jobs = Cluster.splitJobs cmd_strs |
408 |
|
409 |
when (isJust $ optShowCmds opts) $ |
410 |
saveBalanceCommands opts $ Cluster.formatCmds cmd_jobs |
411 |
|
412 |
maybeSaveData (optSaveCluster opts) "balanced" "after balancing" |
413 |
ini_cdata { cdNodes = fin_nl, cdInstances = fin_il } |
414 |
|
415 |
maybePrintInsts showinsts "Final" (Cluster.printInsts fin_nl fin_il) |
416 |
|
417 |
maybePrintNodes shownodes "Final cluster" (Cluster.printNodes fin_nl) |
418 |
|
419 |
when (verbose > 3) $ printStats nl fin_nl |
420 |
|
421 |
eval <- maybeExecJobs opts ord_plc fin_nl il cmd_jobs |
422 |
unless eval (exitWith (ExitFailure 1)) |