HBASE-13965 Stochastic Load Balancer JMX Metrics (Lei Chen)

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/Filter.java

@@ -181,6 +181,10 @@ public abstract class Filter {
      * Seek to next key which is given as hint by the filter.
      */
     SEEK_NEXT_USING_HINT,
+    /**
+     * Include KeyValue and done with row, seek to next.
+     */
+    INCLUDE_AND_SEEK_NEXT_ROW,
 }
 
   /**

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FilterWrapper.java

@@ -134,7 +134,8 @@ final public class FilterWrapper extends Filter {
   public enum FilterRowRetCode {
     NOT_CALLED,
     INCLUDE,     // corresponds to filter.filterRow() returning false
-    EXCLUDE      // corresponds to filter.filterRow() returning true
+    EXCLUDE,     // corresponds to filter.filterRow() returning true
+    INCLUDE_THIS_FAMILY  // exclude other families
   }
   public FilterRowRetCode filterRowCellsWithRet(List<Cell> kvs) throws IOException {
     //To fix HBASE-6429,

hbase-common/src/main/java/org/apache/hadoop/hbase/HConstants.java

@@ -124,6 +124,12 @@ public final class HConstants {
   /** Config for pluggable load balancers */
   public static final String HBASE_MASTER_LOADBALANCER_CLASS = "hbase.master.loadbalancer.class";
 
+  /** Config for balancing the cluster by table */
+  public static final String HBASE_MASTER_LOADBALANCE_BYTABLE = "hbase.master.loadbalance.bytable";
+
+  /** The name of the ensemble table */
+  public static final String ENSEMBLE_TABLE_NAME = "hbase:ensemble";
+
   /** Config for pluggable region normalizer */
   public static final String HBASE_MASTER_NORMALIZER_CLASS =
     "hbase.master.normalizer.class";

hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java

@@ -34,6 +34,7 @@ import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -1256,12 +1257,14 @@ public class HMaster extends HRegionServer implements MasterServices, Server {
         this.assignmentManager.getRegionStates().getAssignmentsByTable();
 
       List<RegionPlan> plans = new ArrayList<RegionPlan>();
+
       //Give the balancer the current cluster state.
       this.balancer.setClusterStatus(getClusterStatus());
-      for (Map<ServerName, List<HRegionInfo>> assignments : assignmentsByTable.values()) {
+      for (Entry<TableName, Map<ServerName, List<HRegionInfo>>> e : assignmentsByTable.entrySet()) {
-        List<RegionPlan> partialPlans = this.balancer.balanceCluster(assignments);
+        List<RegionPlan> partialPlans = this.balancer.balanceCluster(e.getKey(), e.getValue());
         if (partialPlans != null) plans.addAll(partialPlans);
       }
+
       long cutoffTime = System.currentTimeMillis() + maximumBalanceTime;
       int rpCount = 0;  // number of RegionPlans balanced so far
       long totalRegPlanExecTime = 0;

hbase-server/src/main/java/org/apache/hadoop/hbase/master/LoadBalancer.java

@@ -31,6 +31,7 @@ import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.Stoppable;
+import org.apache.hadoop.hbase.TableName;
 
 /**
  * Makes decisions about the placement and movement of Regions across
@@ -64,6 +65,15 @@ public interface LoadBalancer extends Configurable, Stoppable, ConfigurationObse
    */
   void setMasterServices(MasterServices masterServices);
 
+  /**
+   * Perform the major balance operation
+   * @param tableName
+   * @param clusterState
+   * @return List of plans
+   */
+  List<RegionPlan> balanceCluster(TableName tableName, Map<ServerName,
+      List<HRegionInfo>> clusterState) throws HBaseIOException;
+
   /**
    * Perform the major balance operation
    * @param clusterState

hbase-server/src/main/java/org/apache/hadoop/hbase/master/RegionStates.java

@@ -953,13 +953,14 @@ public class RegionStates {
     Map<TableName, Map<ServerName, List<HRegionInfo>>> result =
       new HashMap<TableName, Map<ServerName,List<HRegionInfo>>>();
     synchronized (this) {
-      if (!server.getConfiguration().getBoolean("hbase.master.loadbalance.bytable", false)) {
+      if (!server.getConfiguration().getBoolean(
+            HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE, false)) {
         Map<ServerName, List<HRegionInfo>> svrToRegions =
           new HashMap<ServerName, List<HRegionInfo>>(serverHoldings.size());
         for (Map.Entry<ServerName, Set<HRegionInfo>> e: serverHoldings.entrySet()) {
           svrToRegions.put(e.getKey(), new ArrayList<HRegionInfo>(e.getValue()));
         }
-        result.put(TableName.valueOf("ensemble"), svrToRegions);
+        result.put(TableName.valueOf(HConstants.ENSEMBLE_TABLE_NAME), svrToRegions);
       } else {
         for (Map.Entry<ServerName, Set<HRegionInfo>> e: serverHoldings.entrySet()) {
           for (HRegionInfo hri: e.getValue()) {

hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.java

@@ -45,7 +45,6 @@ import org.apache.hadoop.hbase.RegionLoad;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
-import org.apache.hadoop.hbase.conf.ConfigurationObserver;
 import org.apache.hadoop.hbase.master.LoadBalancer;
 import org.apache.hadoop.hbase.master.MasterServices;
 import org.apache.hadoop.hbase.master.RackManager;
@@ -81,6 +80,21 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
     }
   }
   
+  /**
+   * The constructor that uses the basic MetricsBalancer
+   */
+  protected BaseLoadBalancer() {
+    metricsBalancer = new MetricsBalancer();
+  }
+  
+  /**
+   * This Constructor accepts an instance of MetricsBalancer, 
+   * which will be used instead of creating a new one
+   */
+  protected BaseLoadBalancer(MetricsBalancer metricsBalancer) {
+    this.metricsBalancer = (metricsBalancer != null) ? metricsBalancer : new MetricsBalancer();
+  }
+
   /**
    * An efficient array based implementation similar to ClusterState for keeping
    * the status of the cluster in terms of region assignment and distribution.
@@ -803,7 +817,7 @@ public abstract class BaseLoadBalancer implements LoadBalancer {
     "hbase.balancer.tablesOnMaster";
 
   protected final Set<String> tablesOnMaster = new HashSet<String>();
-  protected final MetricsBalancer metricsBalancer = new MetricsBalancer();
+  protected MetricsBalancer metricsBalancer = null;
   protected ClusterStatus clusterStatus = null;
   protected ServerName masterServerName;
   protected MasterServices services;

hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/FavoredNodeLoadBalancer.java

@@ -28,11 +28,13 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.NamespaceDescriptor;
 import org.apache.hadoop.hbase.ServerLoad;
 import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.master.RackManager;
 import org.apache.hadoop.hbase.master.RegionPlan;
 import org.apache.hadoop.hbase.master.ServerManager;
@@ -345,4 +347,10 @@ public class FavoredNodeLoadBalancer extends BaseLoadBalancer {
       globalFavoredNodesAssignmentPlan.updateFavoredNodesMap(region, favoredNodesForRegion);
     }
   }
+
+  @Override
+  public List<RegionPlan> balanceCluster(TableName tableName,
+      Map<ServerName, List<HRegionInfo>> clusterState) throws HBaseIOException {
+    return balanceCluster(clusterState);
+  }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/MetricsBalancer.java

@@ -25,9 +25,17 @@ import org.apache.hadoop.hbase.CompatibilitySingletonFactory;
  */
 public class MetricsBalancer {
 
-  private final MetricsBalancerSource source;
+  private MetricsBalancerSource source = null;
 
   public MetricsBalancer() {
+    initSource();
+  }
+  
+  /**
+   * A function to instantiate the metrics source. This function can be overridden in its 
+   * subclasses to provide extended sources
+   */
+  protected void initSource() {
     source = CompatibilitySingletonFactory.getInstance(MetricsBalancerSource.class);
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/SimpleLoadBalancer.java

@@ -30,9 +30,11 @@ import java.util.TreeMap;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.classification.InterfaceAudience;
+import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.master.RegionPlan;
 
 import com.google.common.collect.MinMaxPriorityQueue;
@@ -433,4 +435,10 @@ public class SimpleLoadBalancer extends BaseLoadBalancer {
     rp.setDestination(sn);
     regionsToReturn.add(rp);
   }
+
+  @Override
+  public List<RegionPlan> balanceCluster(TableName tableName,
+      Map<ServerName, List<HRegionInfo>> clusterState) throws HBaseIOException {
+    return balanceCluster(clusterState);
+  }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java

@@ -34,10 +34,13 @@ import org.apache.hadoop.hbase.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ClusterStatus;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
+import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.HTableDescriptor;
 import org.apache.hadoop.hbase.RegionLoad;
 import org.apache.hadoop.hbase.ServerLoad;
 import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.master.MasterServices;
 import org.apache.hadoop.hbase.master.RegionPlan;
 import org.apache.hadoop.hbase.master.balancer.BaseLoadBalancer.Cluster.Action;
@@ -102,6 +105,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
       "hbase.master.balancer.stochastic.maxRunningTime";
   protected static final String KEEP_REGION_LOADS =
       "hbase.master.balancer.stochastic.numRegionLoadsToRemember";
+  private static final String TABLE_FUNCTION_SEP = "_";
 
   private static final Random RANDOM = new Random(System.currentTimeMillis());
   private static final Log LOG = LogFactory.getLog(StochasticLoadBalancer.class);
@@ -117,12 +121,28 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
   private CandidateGenerator[] candidateGenerators;
   private CostFromRegionLoadFunction[] regionLoadFunctions;
   private CostFunction[] costFunctions;
+
+  // to save and report costs to JMX
+  private Double curOverallCost = 0d;
+  private Double[] tempFunctionCosts;
+  private Double[] curFunctionCosts;
+
   // Keep locality based picker and cost function to alert them
   // when new services are offered
   private LocalityBasedCandidateGenerator localityCandidateGenerator;
   private LocalityCostFunction localityCost;
   private RegionReplicaHostCostFunction regionReplicaHostCostFunction;
   private RegionReplicaRackCostFunction regionReplicaRackCostFunction;
+  private boolean isByTable = false;
+  private TableName tableName = null;
+  
+  /**
+   * The constructor that pass a MetricsStochasticBalancer to BaseLoadBalancer to replace its
+   * default MetricsBalancer
+   */
+  public StochasticLoadBalancer() {
+    super(new MetricsStochasticBalancer());
+  }
 
   @Override
   public void onConfigurationChange(Configuration conf) {
@@ -140,6 +160,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     maxRunningTime = conf.getLong(MAX_RUNNING_TIME_KEY, maxRunningTime);
 
     numRegionLoadsToRemember = conf.getInt(KEEP_REGION_LOADS, numRegionLoadsToRemember);
+    isByTable = conf.getBoolean(HConstants.HBASE_MASTER_LOADBALANCE_BYTABLE, isByTable);
 
     if (localityCandidateGenerator == null) {
       localityCandidateGenerator = new LocalityBasedCandidateGenerator(services);
@@ -178,6 +199,10 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
       regionLoadFunctions[2],
       regionLoadFunctions[3],
     };
+    
+    curFunctionCosts= new Double[costFunctions.length];
+    tempFunctionCosts= new Double[costFunctions.length];
+
   }
 
   @Override
@@ -192,6 +217,26 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     for(CostFromRegionLoadFunction cost : regionLoadFunctions) {
       cost.setClusterStatus(st);
     }
+
+    // update metrics size
+    try {
+      // by-table or ensemble mode
+      int tablesCount = isByTable ? services.getTableDescriptors().getAll().size() : 1;
+      int functionsCount = getCostFunctionNames().length;
+
+      updateMetricsSize(tablesCount * (functionsCount + 1)); // +1 for overall
+    } catch (Exception e) {
+      LOG.error("failed to get the size of all tables, exception = " + e.getMessage());
+    }
+  }
+  
+  /**
+   * Update the number of metrics that are reported to JMX
+   */
+  public void updateMetricsSize(int size) {
+    if (metricsBalancer instanceof MetricsStochasticBalancer) {
+        ((MetricsStochasticBalancer) metricsBalancer).updateMetricsSize(size);
+    }
   }
 
   @Override
@@ -211,6 +256,13 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     return false;
   }
 
+  @Override
+  public synchronized List<RegionPlan> balanceCluster(TableName tableName, Map<ServerName,
+    List<HRegionInfo>> clusterState) {
+    this.tableName = tableName;
+    return balanceCluster(clusterState);
+  }
+  
   /**
    * Given the cluster state this will try and approach an optimal balance. This
    * should always approach the optimal state given enough steps.
@@ -222,6 +274,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     if (plans != null || clusterState == null || clusterState.size() <= 1) {
       return plans;
     }
+
     if (masterServerName != null && clusterState.containsKey(masterServerName)) {
       if (clusterState.size() <= 2) {
         return null;
@@ -243,6 +296,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     //of all the regions in the table(s) (that's true today)
     // Keep track of servers to iterate through them.
     Cluster cluster = new Cluster(clusterState, loads, finder, rackManager);
+
     if (!needsBalance(cluster)) {
       return null;
     }
@@ -252,6 +306,10 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     initCosts(cluster);
 
     double currentCost = computeCost(cluster, Double.MAX_VALUE);
+    curOverallCost = currentCost;
+    for (int i = 0; i < this.curFunctionCosts.length; i++) {
+      curFunctionCosts[i] = tempFunctionCosts[i];
+    }
 
     double initCost = currentCost;
     double newCost = currentCost;
@@ -278,6 +336,12 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
       // Should this be kept?
       if (newCost < currentCost) {
         currentCost = newCost;
+
+        // save for JMX
+        curOverallCost = currentCost;
+        for (int i = 0; i < this.curFunctionCosts.length; i++) {
+          curFunctionCosts[i] = tempFunctionCosts[i];
+        }
       } else {
         // Put things back the way they were before.
         // TODO: undo by remembering old values
@@ -296,6 +360,8 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
 
     metricsBalancer.balanceCluster(endTime - startTime);
 
+    // update costs metrics
+    updateStochasticCosts(tableName, curOverallCost, curFunctionCosts);
     if (initCost > currentCost) {
       plans = createRegionPlans(cluster);
       if (LOG.isDebugEnabled()) {
@@ -305,6 +371,7 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
             + plans.size() + " regions; Going from a computed cost of "
             + initCost + " to a new cost of " + currentCost);
       }
+      
       return plans;
     }
     if (LOG.isDebugEnabled()) {
@@ -315,6 +382,32 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     return null;
   }
   
+  /**
+   * update costs to JMX
+   */
+  private void updateStochasticCosts(TableName tableName, Double overall, Double[] subCosts) {
+    if (tableName == null) return;
+
+    // check if the metricsBalancer is MetricsStochasticBalancer before casting
+    if (metricsBalancer instanceof MetricsStochasticBalancer) {
+      MetricsStochasticBalancer balancer = (MetricsStochasticBalancer) metricsBalancer;
+      // overall cost
+      balancer.updateStochasticCost(tableName.getNameAsString(), 
+        "Overall", "Overall cost", overall);
+
+      // each cost function
+      for (int i = 0; i < costFunctions.length; i++) {
+        CostFunction costFunction = costFunctions[i];
+        String costFunctionName = costFunction.getClass().getSimpleName();
+        Double costPercent = (overall == 0) ? 0 : (subCosts[i] / overall);
+        // TODO: cost function may need a specific description
+        balancer.updateStochasticCost(tableName.getNameAsString(), costFunctionName,
+          "The percent of " + costFunctionName, costPercent);
+      }
+    }
+  }
+
+
   /**
    * Create all of the RegionPlan's needed to move from the initial cluster state to the desired
    * state.
@@ -390,6 +483,20 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
     }
   }
 
+  /**
+   * Get the names of the cost functions
+   */
+  public String[] getCostFunctionNames() {
+    if (costFunctions == null) return null;
+    String[] ret = new String[costFunctions.length];
+    for (int i = 0; i < costFunctions.length; i++) {
+      CostFunction c = costFunctions[i];
+      ret[i] = c.getClass().getSimpleName();
+    }
+
+    return ret;
+  }
+
   /**
    * This is the main cost function.  It will compute a cost associated with a proposed cluster
    * state.  All different costs will be combined with their multipliers to produce a double cost.
@@ -402,17 +509,25 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
   protected double computeCost(Cluster cluster, double previousCost) {
     double total = 0;
 
-    for (CostFunction c:costFunctions) {
+    for (int i = 0; i < costFunctions.length; i++) {
+      CostFunction c = costFunctions[i];
+      this.tempFunctionCosts[i] = 0.0;
+      
       if (c.getMultiplier() <= 0) {
         continue;
       }
 
-      total += c.getMultiplier() * c.cost();
+      Float multiplier = c.getMultiplier();
+      Double cost = c.cost();
+
+      this.tempFunctionCosts[i] = multiplier*cost;
+      total += this.tempFunctionCosts[i];
 
       if (total > previousCost) {
-        return total;
+        break;
       }
     }
+   
     return total;
   }
 
@@ -1318,7 +1433,8 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
 
     public RegionReplicaRackCostFunction(Configuration conf) {
       super(conf);
-      this.setMultiplier(conf.getFloat(REGION_REPLICA_RACK_COST_KEY, DEFAULT_REGION_REPLICA_RACK_COST_KEY));
+      this.setMultiplier(conf.getFloat(REGION_REPLICA_RACK_COST_KEY, 
+        DEFAULT_REGION_REPLICA_RACK_COST_KEY));
     }
 
     @Override
@@ -1390,4 +1506,11 @@ public class StochasticLoadBalancer extends BaseLoadBalancer {
       return rl.getStorefileSizeMB();
     }
   }
+  
+  /**
+   * A helper function to compose the attribute name from tablename and costfunction name
+   */
+  public static String composeAttributeName(String tableName, String costFunctionName) {
+    return tableName + TABLE_FUNCTION_SEP + costFunctionName;
+  }
 }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/ScanQueryMatcher.java

@@ -444,7 +444,17 @@ public class ScanQueryMatcher {
       colChecker = columns.checkVersions(cell, timestamp, typeByte,
           mvccVersion > maxReadPointToTrackVersions);
       //Optimize with stickyNextRow
-      stickyNextRow = colChecker == MatchCode.INCLUDE_AND_SEEK_NEXT_ROW ? true : stickyNextRow;
+      boolean seekNextRowFromEssential = filterResponse == ReturnCode.INCLUDE_AND_SEEK_NEXT_ROW &&
+          filter.isFamilyEssential(cell.getFamilyArray());
+      if (colChecker == MatchCode.INCLUDE_AND_SEEK_NEXT_ROW || seekNextRowFromEssential) {
+        stickyNextRow = true;
+      }
+      if (filterResponse == ReturnCode.INCLUDE_AND_SEEK_NEXT_ROW) {
+        if (colChecker != MatchCode.SKIP) {
+          return MatchCode.INCLUDE_AND_SEEK_NEXT_ROW;
+        }
+        return MatchCode.SEEK_NEXT_ROW;
+      }
       return (filterResponse == ReturnCode.INCLUDE_AND_NEXT_COL &&
           colChecker == MatchCode.INCLUDE) ? MatchCode.INCLUDE_AND_SEEK_NEXT_COL
           : colChecker;

hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestBaseLoadBalancer.java

@@ -38,6 +38,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
+import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
@@ -108,6 +109,12 @@ public class TestBaseLoadBalancer extends BalancerTestBase {
       return null;
     }
 
+    @Override
+    public List<RegionPlan> balanceCluster(TableName tableName,
+        Map<ServerName, List<HRegionInfo>> clusterState) throws HBaseIOException {
+      return null;
+    }
+
   }
 
   /**