virajjasani commented on a change in pull request #2044: URL: https://github.com/apache/hbase/pull/2044#discussion_r452738026
########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java ########## @@ -827,26 +828,34 @@ protected double scale(double min, double max, double value) { */ static class MoveCostFunction extends CostFunction { private static final String MOVE_COST_KEY = "hbase.master.balancer.stochastic.moveCost"; + private static final String MOVE_COST_OFFPEAK_KEY = "hbase.master.balancer.stochastic.moveCost.offpeak"; private static final String MAX_MOVES_PERCENT_KEY = "hbase.master.balancer.stochastic.maxMovePercent"; - private static final float DEFAULT_MOVE_COST = 7; + @VisibleForTesting + protected static final float DEFAULT_MOVE_COST = 7; + protected static final float DEFAULT_MOVE_COST_OFFPEAK = 3; Review comment: Can we please avoid `@VisibleForTesting` and make them private? On the other hand, use default value directly in test cases. If default values change here and test is not updated, it is anyways going to fail. ########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java ########## @@ -827,26 +828,34 @@ protected double scale(double min, double max, double value) { */ static class MoveCostFunction extends CostFunction { private static final String MOVE_COST_KEY = "hbase.master.balancer.stochastic.moveCost"; + private static final String MOVE_COST_OFFPEAK_KEY = "hbase.master.balancer.stochastic.moveCost.offpeak"; private static final String MAX_MOVES_PERCENT_KEY = "hbase.master.balancer.stochastic.maxMovePercent"; - private static final float DEFAULT_MOVE_COST = 7; + @VisibleForTesting + protected static final float DEFAULT_MOVE_COST = 7; + protected static final float DEFAULT_MOVE_COST_OFFPEAK = 3; private static final int DEFAULT_MAX_MOVES = 600; private static final float DEFAULT_MAX_MOVE_PERCENT = 0.25f; private final float maxMovesPercent; + private final Configuration conf; MoveCostFunction(Configuration conf) { super(conf); - - // Move cost multiplier should be the same cost or higher than the rest of the costs to ensure - // that large benefits are need to overcome the cost of a move. - this.setMultiplier(conf.getFloat(MOVE_COST_KEY, DEFAULT_MOVE_COST)); + this.conf = conf; // What percent of the number of regions a single run of the balancer can move. maxMovesPercent = conf.getFloat(MAX_MOVES_PERCENT_KEY, DEFAULT_MAX_MOVE_PERCENT); } @Override protected double cost() { + // Move cost multiplier should be the same cost or higher than the rest of the costs to ensure + // that large benefits are need to overcome the cost of a move. + if (OffPeakHours.getInstance(conf).isOffPeakHour()) { + this.setMultiplier(conf.getFloat(MOVE_COST_OFFPEAK_KEY, DEFAULT_MOVE_COST_OFFPEAK)); + } else { + this.setMultiplier(conf.getFloat(MOVE_COST_KEY, DEFAULT_MOVE_COST)); + } Review comment: Why not keep this logic in `MoveCostFunction` constructor? ########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/StochasticLoadBalancer.java ########## @@ -827,26 +828,34 @@ protected double scale(double min, double max, double value) { */ static class MoveCostFunction extends CostFunction { private static final String MOVE_COST_KEY = "hbase.master.balancer.stochastic.moveCost"; + private static final String MOVE_COST_OFFPEAK_KEY = "hbase.master.balancer.stochastic.moveCost.offpeak"; Review comment: nit: please limit 100 chars in one line ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org