detailyang commented on a change in pull request #2586: Optimize RoundRobinLoadBalance URL: https://github.com/apache/incubator-dubbo/pull/2586#discussion_r223175919
########## File path: dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/RoundRobinLoadBalance.java ########## @@ -21,83 +21,64 @@ import org.apache.dubbo.rpc.Invocation; import org.apache.dubbo.rpc.Invoker; -import java.util.LinkedHashMap; +import java.util.ArrayList; import java.util.List; -import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; /** * Round robin load balance. - * */ public class RoundRobinLoadBalance extends AbstractLoadBalance { public static final String NAME = "roundrobin"; private final ConcurrentMap<String, AtomicPositiveInteger> sequences = new ConcurrentHashMap<String, AtomicPositiveInteger>(); + private final ConcurrentMap<String, AtomicPositiveInteger> indexSeqs = new ConcurrentHashMap<String, AtomicPositiveInteger>(); + @Override protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation invocation) { String key = invokers.get(0).getUrl().getServiceKey() + "." + invocation.getMethodName(); int length = invokers.size(); // Number of invokers int maxWeight = 0; // The maximum weight int minWeight = Integer.MAX_VALUE; // The minimum weight - final LinkedHashMap<Invoker<T>, IntegerWrapper> invokerToWeightMap = new LinkedHashMap<Invoker<T>, IntegerWrapper>(); - int weightSum = 0; + final List<Invoker<T>> nonZeroWeightedInvokers = new ArrayList<>(); for (int i = 0; i < length; i++) { int weight = getWeight(invokers.get(i), invocation); maxWeight = Math.max(maxWeight, weight); // Choose the maximum weight minWeight = Math.min(minWeight, weight); // Choose the minimum weight if (weight > 0) { - invokerToWeightMap.put(invokers.get(i), new IntegerWrapper(weight)); - weightSum += weight; + nonZeroWeightedInvokers.add(invokers.get(i)); } } AtomicPositiveInteger sequence = sequences.get(key); if (sequence == null) { sequences.putIfAbsent(key, new AtomicPositiveInteger()); sequence = sequences.get(key); } - int currentSequence = sequence.getAndIncrement(); + if (maxWeight > 0 && minWeight < maxWeight) { - int mod = currentSequence % weightSum; - for (int i = 0; i < maxWeight; i++) { - for (Map.Entry<Invoker<T>, IntegerWrapper> each : invokerToWeightMap.entrySet()) { - final Invoker<T> k = each.getKey(); - final IntegerWrapper v = each.getValue(); - if (mod == 0 && v.getValue() > 0) { - return k; - } - if (v.getValue() > 0) { - v.decrement(); - mod--; - } + AtomicPositiveInteger indexSeq = indexSeqs.get(key); + if (indexSeq == null) { + indexSeqs.putIfAbsent(key, new AtomicPositiveInteger(-1)); + indexSeq = indexSeqs.get(key); + } + length = nonZeroWeightedInvokers.size(); + while (true) { + int index = indexSeq.incrementAndGet() % length; + int currentWeight; + if (index == 0) { + currentWeight = sequence.incrementAndGet() % maxWeight; + }else { Review comment: space need:) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on 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 With regards, Apache Git Services