From 245229055edd7727fc287c9683365cbac02b64ee Mon Sep 17 00:00:00 2001
From: haxiaolin <haxiaolin@apache.org>
Date: Mon, 28 Mar 2022 18:19:01 +0800
Subject: [PATCH] Revert "HBASE-26872 Load rate calculator for cost functions
 should be more precise (#4253)"

This reverts commit 568b335b443acc33975927d96297b332ae4b4287.
---
 .../CostFromRegionLoadAsRateFunction.java     |  4 +--
 .../balancer/TestStochasticLoadBalancer.java  | 28 ++-----------------
 2 files changed, 4 insertions(+), 28 deletions(-)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CostFromRegionLoadAsRateFunction.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CostFromRegionLoadAsRateFunction.java
index e6d0cf83174..88af49e1a06 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CostFromRegionLoadAsRateFunction.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/balancer/CostFromRegionLoadAsRateFunction.java
@@ -42,9 +42,9 @@ abstract class CostFromRegionLoadAsRateFunction extends CostFromRegionLoadFuncti
     double cost = 0;
     do {
       double current = getCostFromRl(iter.next());
-      cost += current >= previous ? current - previous : current;
+      cost += current - previous;
       previous = current;
     } while (iter.hasNext());
     return Math.max(0, cost / (regionLoadList.size() - 1));
   }
-}
+}
\ No newline at end of file
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancer.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancer.java
index bd80e15b2cd..9f9ac84dd21 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancer.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/master/balancer/TestStochasticLoadBalancer.java
@@ -23,6 +23,7 @@ import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -49,6 +50,7 @@ import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
+
 import org.apache.hbase.thirdparty.org.apache.commons.collections4.CollectionUtils;
 
 @Category({ MasterTests.class, MediumTests.class })
@@ -447,32 +449,6 @@ public class TestStochasticLoadBalancer extends BalancerTestBase {
     assertEquals(2.5, result, 0.01);
   }
 
-  @Test
-  public void testRegionLoadCostWhenDecrease() {
-    List<BalancerRegionLoad> regionLoads = new ArrayList<>();
-    // test region loads of [1,2,1,4]
-    for (int i = 1; i < 5; i++) {
-      int load = i == 3 ? 1 : i;
-      BalancerRegionLoad regionLoad = mock(BalancerRegionLoad.class);
-      when(regionLoad.getReadRequestsCount()).thenReturn((long)load);
-      when(regionLoad.getCpRequestsCount()).thenReturn((long)load);
-      regionLoads.add(regionLoad);
-    }
-
-    Configuration conf = HBaseConfiguration.create();
-    ReadRequestCostFunction readCostFunction =
-      new ReadRequestCostFunction(conf);
-    double rateResult = readCostFunction.getRegionLoadCost(regionLoads);
-    // read requests are treated as a rate so the average rate here is simply 1
-    assertEquals(1.67, rateResult, 0.01);
-
-    CPRequestCostFunction cpCostFunction =
-      new CPRequestCostFunction(conf);
-    rateResult = cpCostFunction.getRegionLoadCost(regionLoads);
-    // coprocessor requests are treated as a rate so the average rate here is simply 1
-    assertEquals(1.67, rateResult, 0.01);
-  }
-
   @Test
   public void testLosingRs() throws Exception {
     int numNodes = 3;