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Posted to commits@hbase.apache.org by gi...@apache.org on 2018/10/24 14:55:01 UTC
[27/51] [partial] hbase-site git commit: Published site at
3fe8649b2c9ba1271c25e8f476548907e4c7a90d.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/8f09a71d/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.MoveCostFunction.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.MoveCostFunction.html b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.MoveCostFunction.html
index c7d99b2..9d1542c 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.MoveCostFunction.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.MoveCostFunction.html
@@ -382,1357 +382,1365 @@
<span class="sourceLineNo">374</span> for (int i = 0; i < this.curFunctionCosts.length; i++) {<a name="line.374"></a>
<span class="sourceLineNo">375</span> curFunctionCosts[i] = tempFunctionCosts[i];<a name="line.375"></a>
<span class="sourceLineNo">376</span> }<a name="line.376"></a>
-<span class="sourceLineNo">377</span> LOG.info("start StochasticLoadBalancer.balancer, initCost=" + currentCost + ", functionCost="<a name="line.377"></a>
-<span class="sourceLineNo">378</span> + functionCost());<a name="line.378"></a>
+<span class="sourceLineNo">377</span> double initCost = currentCost;<a name="line.377"></a>
+<span class="sourceLineNo">378</span> double newCost = currentCost;<a name="line.378"></a>
<span class="sourceLineNo">379</span><a name="line.379"></a>
-<span class="sourceLineNo">380</span> double initCost = currentCost;<a name="line.380"></a>
-<span class="sourceLineNo">381</span> double newCost = currentCost;<a name="line.381"></a>
-<span class="sourceLineNo">382</span><a name="line.382"></a>
-<span class="sourceLineNo">383</span> long computedMaxSteps;<a name="line.383"></a>
-<span class="sourceLineNo">384</span> if (runMaxSteps) {<a name="line.384"></a>
-<span class="sourceLineNo">385</span> computedMaxSteps = Math.max(this.maxSteps,<a name="line.385"></a>
-<span class="sourceLineNo">386</span> ((long)cluster.numRegions * (long)this.stepsPerRegion * (long)cluster.numServers));<a name="line.386"></a>
-<span class="sourceLineNo">387</span> } else {<a name="line.387"></a>
-<span class="sourceLineNo">388</span> computedMaxSteps = Math.min(this.maxSteps,<a name="line.388"></a>
-<span class="sourceLineNo">389</span> ((long)cluster.numRegions * (long)this.stepsPerRegion * (long)cluster.numServers));<a name="line.389"></a>
-<span class="sourceLineNo">390</span> }<a name="line.390"></a>
-<span class="sourceLineNo">391</span> // Perform a stochastic walk to see if we can get a good fit.<a name="line.391"></a>
-<span class="sourceLineNo">392</span> long step;<a name="line.392"></a>
-<span class="sourceLineNo">393</span><a name="line.393"></a>
-<span class="sourceLineNo">394</span> for (step = 0; step < computedMaxSteps; step++) {<a name="line.394"></a>
-<span class="sourceLineNo">395</span> Cluster.Action action = nextAction(cluster);<a name="line.395"></a>
-<span class="sourceLineNo">396</span><a name="line.396"></a>
-<span class="sourceLineNo">397</span> if (action.type == Type.NULL) {<a name="line.397"></a>
-<span class="sourceLineNo">398</span> continue;<a name="line.398"></a>
-<span class="sourceLineNo">399</span> }<a name="line.399"></a>
-<span class="sourceLineNo">400</span><a name="line.400"></a>
-<span class="sourceLineNo">401</span> cluster.doAction(action);<a name="line.401"></a>
-<span class="sourceLineNo">402</span> updateCostsWithAction(cluster, action);<a name="line.402"></a>
-<span class="sourceLineNo">403</span><a name="line.403"></a>
-<span class="sourceLineNo">404</span> newCost = computeCost(cluster, currentCost);<a name="line.404"></a>
-<span class="sourceLineNo">405</span><a name="line.405"></a>
-<span class="sourceLineNo">406</span> // Should this be kept?<a name="line.406"></a>
-<span class="sourceLineNo">407</span> if (newCost < currentCost) {<a name="line.407"></a>
-<span class="sourceLineNo">408</span> currentCost = newCost;<a name="line.408"></a>
-<span class="sourceLineNo">409</span><a name="line.409"></a>
-<span class="sourceLineNo">410</span> // save for JMX<a name="line.410"></a>
-<span class="sourceLineNo">411</span> curOverallCost = currentCost;<a name="line.411"></a>
-<span class="sourceLineNo">412</span> for (int i = 0; i < this.curFunctionCosts.length; i++) {<a name="line.412"></a>
-<span class="sourceLineNo">413</span> curFunctionCosts[i] = tempFunctionCosts[i];<a name="line.413"></a>
-<span class="sourceLineNo">414</span> }<a name="line.414"></a>
-<span class="sourceLineNo">415</span> } else {<a name="line.415"></a>
-<span class="sourceLineNo">416</span> // Put things back the way they were before.<a name="line.416"></a>
-<span class="sourceLineNo">417</span> // TODO: undo by remembering old values<a name="line.417"></a>
-<span class="sourceLineNo">418</span> Action undoAction = action.undoAction();<a name="line.418"></a>
-<span class="sourceLineNo">419</span> cluster.doAction(undoAction);<a name="line.419"></a>
-<span class="sourceLineNo">420</span> updateCostsWithAction(cluster, undoAction);<a name="line.420"></a>
-<span class="sourceLineNo">421</span> }<a name="line.421"></a>
-<span class="sourceLineNo">422</span><a name="line.422"></a>
-<span class="sourceLineNo">423</span> if (EnvironmentEdgeManager.currentTime() - startTime ><a name="line.423"></a>
-<span class="sourceLineNo">424</span> maxRunningTime) {<a name="line.424"></a>
-<span class="sourceLineNo">425</span> break;<a name="line.425"></a>
-<span class="sourceLineNo">426</span> }<a name="line.426"></a>
-<span class="sourceLineNo">427</span> }<a name="line.427"></a>
-<span class="sourceLineNo">428</span> long endTime = EnvironmentEdgeManager.currentTime();<a name="line.428"></a>
-<span class="sourceLineNo">429</span><a name="line.429"></a>
-<span class="sourceLineNo">430</span> metricsBalancer.balanceCluster(endTime - startTime);<a name="line.430"></a>
-<span class="sourceLineNo">431</span><a name="line.431"></a>
-<span class="sourceLineNo">432</span> // update costs metrics<a name="line.432"></a>
-<span class="sourceLineNo">433</span> updateStochasticCosts(tableName, curOverallCost, curFunctionCosts);<a name="line.433"></a>
-<span class="sourceLineNo">434</span> if (initCost > currentCost) {<a name="line.434"></a>
-<span class="sourceLineNo">435</span> plans = createRegionPlans(cluster);<a name="line.435"></a>
-<span class="sourceLineNo">436</span> LOG.info("Finished computing new load balance plan. Computation took {}" +<a name="line.436"></a>
-<span class="sourceLineNo">437</span> " to try {} different iterations. Found a solution that moves " +<a name="line.437"></a>
-<span class="sourceLineNo">438</span> "{} regions; Going from a computed cost of {}" +<a name="line.438"></a>
-<span class="sourceLineNo">439</span> " to a new cost of {}", java.time.Duration.ofMillis(endTime - startTime),<a name="line.439"></a>
-<span class="sourceLineNo">440</span> step, plans.size(), initCost, currentCost);<a name="line.440"></a>
-<span class="sourceLineNo">441</span> return plans;<a name="line.441"></a>
-<span class="sourceLineNo">442</span> }<a name="line.442"></a>
-<span class="sourceLineNo">443</span> LOG.info("Could not find a better load balance plan. Tried {} different configurations in " +<a name="line.443"></a>
-<span class="sourceLineNo">444</span> "{}, and did not find anything with a computed cost less than {}", step,<a name="line.444"></a>
-<span class="sourceLineNo">445</span> java.time.Duration.ofMillis(endTime - startTime), initCost);<a name="line.445"></a>
-<span class="sourceLineNo">446</span> return null;<a name="line.446"></a>
-<span class="sourceLineNo">447</span> }<a name="line.447"></a>
-<span class="sourceLineNo">448</span><a name="line.448"></a>
-<span class="sourceLineNo">449</span> /**<a name="line.449"></a>
-<span class="sourceLineNo">450</span> * update costs to JMX<a name="line.450"></a>
-<span class="sourceLineNo">451</span> */<a name="line.451"></a>
-<span class="sourceLineNo">452</span> private void updateStochasticCosts(TableName tableName, Double overall, Double[] subCosts) {<a name="line.452"></a>
-<span class="sourceLineNo">453</span> if (tableName == null) return;<a name="line.453"></a>
-<span class="sourceLineNo">454</span><a name="line.454"></a>
-<span class="sourceLineNo">455</span> // check if the metricsBalancer is MetricsStochasticBalancer before casting<a name="line.455"></a>
-<span class="sourceLineNo">456</span> if (metricsBalancer instanceof MetricsStochasticBalancer) {<a name="line.456"></a>
-<span class="sourceLineNo">457</span> MetricsStochasticBalancer balancer = (MetricsStochasticBalancer) metricsBalancer;<a name="line.457"></a>
-<span class="sourceLineNo">458</span> // overall cost<a name="line.458"></a>
-<span class="sourceLineNo">459</span> balancer.updateStochasticCost(tableName.getNameAsString(),<a name="line.459"></a>
-<span class="sourceLineNo">460</span> "Overall", "Overall cost", overall);<a name="line.460"></a>
-<span class="sourceLineNo">461</span><a name="line.461"></a>
-<span class="sourceLineNo">462</span> // each cost function<a name="line.462"></a>
-<span class="sourceLineNo">463</span> for (int i = 0; i < costFunctions.length; i++) {<a name="line.463"></a>
-<span class="sourceLineNo">464</span> CostFunction costFunction = costFunctions[i];<a name="line.464"></a>
-<span class="sourceLineNo">465</span> String costFunctionName = costFunction.getClass().getSimpleName();<a name="line.465"></a>
-<span class="sourceLineNo">466</span> Double costPercent = (overall == 0) ? 0 : (subCosts[i] / overall);<a name="line.466"></a>
-<span class="sourceLineNo">467</span> // TODO: cost function may need a specific description<a name="line.467"></a>
-<span class="sourceLineNo">468</span> balancer.updateStochasticCost(tableName.getNameAsString(), costFunctionName,<a name="line.468"></a>
-<span class="sourceLineNo">469</span> "The percent of " + costFunctionName, costPercent);<a name="line.469"></a>
-<span class="sourceLineNo">470</span> }<a name="line.470"></a>
-<span class="sourceLineNo">471</span> }<a name="line.471"></a>
-<span class="sourceLineNo">472</span> }<a name="line.472"></a>
-<span class="sourceLineNo">473</span><a name="line.473"></a>
-<span class="sourceLineNo">474</span> private String functionCost() {<a name="line.474"></a>
-<span class="sourceLineNo">475</span> StringBuilder builder = new StringBuilder();<a name="line.475"></a>
-<span class="sourceLineNo">476</span> for (CostFunction c:costFunctions) {<a name="line.476"></a>
-<span class="sourceLineNo">477</span> builder.append(c.getClass().getSimpleName());<a name="line.477"></a>
-<span class="sourceLineNo">478</span> builder.append(" : (");<a name="line.478"></a>
-<span class="sourceLineNo">479</span> builder.append(c.getMultiplier());<a name="line.479"></a>
-<span class="sourceLineNo">480</span> builder.append(", ");<a name="line.480"></a>
-<span class="sourceLineNo">481</span> builder.append(c.cost());<a name="line.481"></a>
-<span class="sourceLineNo">482</span> builder.append("); ");<a name="line.482"></a>
-<span class="sourceLineNo">483</span> }<a name="line.483"></a>
-<span class="sourceLineNo">484</span> return builder.toString();<a name="line.484"></a>
-<span class="sourceLineNo">485</span> }<a name="line.485"></a>
-<span class="sourceLineNo">486</span><a name="line.486"></a>
-<span class="sourceLineNo">487</span> /**<a name="line.487"></a>
-<span class="sourceLineNo">488</span> * Create all of the RegionPlan's needed to move from the initial cluster state to the desired<a name="line.488"></a>
-<span class="sourceLineNo">489</span> * state.<a name="line.489"></a>
-<span class="sourceLineNo">490</span> *<a name="line.490"></a>
-<span class="sourceLineNo">491</span> * @param cluster The state of the cluster<a name="line.491"></a>
-<span class="sourceLineNo">492</span> * @return List of RegionPlan's that represent the moves needed to get to desired final state.<a name="line.492"></a>
-<span class="sourceLineNo">493</span> */<a name="line.493"></a>
-<span class="sourceLineNo">494</span> private List<RegionPlan> createRegionPlans(Cluster cluster) {<a name="line.494"></a>
-<span class="sourceLineNo">495</span> List<RegionPlan> plans = new LinkedList<>();<a name="line.495"></a>
-<span class="sourceLineNo">496</span> for (int regionIndex = 0;<a name="line.496"></a>
-<span class="sourceLineNo">497</span> regionIndex < cluster.regionIndexToServerIndex.length; regionIndex++) {<a name="line.497"></a>
-<span class="sourceLineNo">498</span> int initialServerIndex = cluster.initialRegionIndexToServerIndex[regionIndex];<a name="line.498"></a>
-<span class="sourceLineNo">499</span> int newServerIndex = cluster.regionIndexToServerIndex[regionIndex];<a name="line.499"></a>
-<span class="sourceLineNo">500</span><a name="line.500"></a>
-<span class="sourceLineNo">501</span> if (initialServerIndex != newServerIndex) {<a name="line.501"></a>
-<span class="sourceLineNo">502</span> RegionInfo region = cluster.regions[regionIndex];<a name="line.502"></a>
-<span class="sourceLineNo">503</span> ServerName initialServer = cluster.servers[initialServerIndex];<a name="line.503"></a>
-<span class="sourceLineNo">504</span> ServerName newServer = cluster.servers[newServerIndex];<a name="line.504"></a>
-<span class="sourceLineNo">505</span><a name="line.505"></a>
-<span class="sourceLineNo">506</span> if (LOG.isTraceEnabled()) {<a name="line.506"></a>
-<span class="sourceLineNo">507</span> LOG.trace("Moving Region " + region.getEncodedName() + " from server "<a name="line.507"></a>
-<span class="sourceLineNo">508</span> + initialServer.getHostname() + " to " + newServer.getHostname());<a name="line.508"></a>
-<span class="sourceLineNo">509</span> }<a name="line.509"></a>
-<span class="sourceLineNo">510</span> RegionPlan rp = new RegionPlan(region, initialServer, newServer);<a name="line.510"></a>
-<span class="sourceLineNo">511</span> plans.add(rp);<a name="line.511"></a>
-<span class="sourceLineNo">512</span> }<a name="line.512"></a>
-<span class="sourceLineNo">513</span> }<a name="line.513"></a>
-<span class="sourceLineNo">514</span> return plans;<a name="line.514"></a>
-<span class="sourceLineNo">515</span> }<a name="line.515"></a>
-<span class="sourceLineNo">516</span><a name="line.516"></a>
-<span class="sourceLineNo">517</span> /**<a name="line.517"></a>
-<span class="sourceLineNo">518</span> * Store the current region loads.<a name="line.518"></a>
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-<span class="sourceLineNo">521</span> // We create a new hashmap so that regions that are no longer there are removed.<a name="line.521"></a>
-<span class="sourceLineNo">522</span> // However we temporarily need the old loads so we can use them to keep the rolling average.<a name="line.522"></a>
-<span class="sourceLineNo">523</span> Map<String, Deque<BalancerRegionLoad>> oldLoads = loads;<a name="line.523"></a>
-<span class="sourceLineNo">524</span> loads = new HashMap<>();<a name="line.524"></a>
-<span class="sourceLineNo">525</span><a name="line.525"></a>
-<span class="sourceLineNo">526</span> clusterStatus.getLiveServerMetrics().forEach((ServerName sn, ServerMetrics sm) -> {<a name="line.526"></a>
-<span class="sourceLineNo">527</span> sm.getRegionMetrics().forEach((byte[] regionName, RegionMetrics rm) -> {<a name="line.527"></a>
-<span class="sourceLineNo">528</span> Deque<BalancerRegionLoad> rLoads = oldLoads.get(Bytes.toString(regionName));<a name="line.528"></a>
-<span class="sourceLineNo">529</span> if (rLoads == null) {<a name="line.529"></a>
-<span class="sourceLineNo">530</span> rLoads = new ArrayDeque<>(numRegionLoadsToRemember + 1);<a name="line.530"></a>
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-<span class="sourceLineNo">532</span> rLoads.remove();<a name="line.532"></a>
-<span class="sourceLineNo">533</span> }<a name="line.533"></a>
-<span class="sourceLineNo">534</span> rLoads.add(new BalancerRegionLoad(rm));<a name="line.534"></a>
-<span class="sourceLineNo">535</span> loads.put(Bytes.toString(regionName), rLoads);<a name="line.535"></a>
-<span class="sourceLineNo">536</span> });<a name="line.536"></a>
-<span class="sourceLineNo">537</span> });<a name="line.537"></a>
-<span class="sourceLineNo">538</span><a name="line.538"></a>
-<span class="sourceLineNo">539</span> for(CostFromRegionLoadFunction cost : regionLoadFunctions) {<a name="line.539"></a>
-<span class="sourceLineNo">540</span> cost.setLoads(loads);<a name="line.540"></a>
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-<span class="sourceLineNo">546</span> c.init(cluster);<a name="line.546"></a>
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-<span class="sourceLineNo">549</span><a name="line.549"></a>
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-<span class="sourceLineNo">552</span> c.postAction(action);<a name="line.552"></a>
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-<span class="sourceLineNo">556</span> /**<a name="line.556"></a>
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-<span class="sourceLineNo">563</span> CostFunction c = costFunctions[i];<a name="line.563"></a>
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+<span class="sourceLineNo">381</span> if (runMaxSteps) {<a name="line.381"></a>
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+<span class="sourceLineNo">389</span> LOG.warn("calculatedMaxSteps:{} for loadbalancer's stochastic walk is larger than "<a name="line.389"></a>
+<span class="sourceLineNo">390</span> + "maxSteps:{}. Hence load balancing may not work well. Setting parameter "<a name="line.390"></a>
+<span class="sourceLineNo">391</span> + "\"hbase.master.balancer.stochastic.runMaxSteps\" to true can overcome this issue."<a name="line.391"></a>
+<span class="sourceLineNo">392</span> + "(This config change does not require service restart)", calculatedMaxSteps,<a name="line.392"></a>
+<span class="sourceLineNo">393</span> maxRunningTime);<a name="line.393"></a>
+<span class="sourceLineNo">394</span> }<a name="line.394"></a>
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+<span class="sourceLineNo">396</span> LOG.info("start StochasticLoadBalancer.balancer, initCost=" + currentCost + ", functionCost="<a name="line.396"></a>
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+<span class="sourceLineNo">440</span> // update costs metrics<a name="line.440"></a>
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+<span class="sourceLineNo">451</span> LOG.info("Could not find a better load balance plan. Tried {} different configurations in " +<a name="line.451"></a>
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+<span class="sourceLineNo">456</span><a name="line.456"></a>
+<span class="sourceLineNo">457</span> /**<a name="line.457"></a>
+<span class="sourceLineNo">458</span> * update costs to JMX<a name="line.458"></a>
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+<span class="sourceLineNo">462</span><a name="line.462"></a>
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+<span class="sourceLineNo">467</span> balancer.updateStochasticCost(tableName.getNameAsString(),<a name="line.467"></a>
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+<span class="sourceLineNo">469</span><a name="line.469"></a>
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+<span class="sourceLineNo">486</span> builder.append(" : (");<a name="line.486"></a>
+<span class="sourceLineNo">487</span> builder.append(c.getMultiplier());<a name="line.487"></a>
+<span class="sourceLineNo">488</span> builder.append(", ");<a name="line.488"></a>
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+<span class="sourceLineNo">516</span> + initialServer.getHostname() + " to " + newServer.getHostname());<a name="line.516"></a>
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