Fixed - `RMultimap.sizeInMemory()` method doesn't take in account size of all associated objects #3034

redisson/src/main/java/org/redisson/RedissonMultimap.java

@@ -54,6 +54,20 @@ public abstract class RedissonMultimap<K, V> extends RedissonExpirable implement
         prefix = suffixName(getName(), "");
     }
 
+    @Override
+    public RFuture<Long> sizeInMemoryAsync() {
+        return commandExecutor.evalWriteAsync(getName(), StringCodec.INSTANCE, RedisCommands.EVAL_LONG,
+                "local keys = redis.call('hgetall', KEYS[1]); " +
+                "local size = 0; " +
+                "for i, v in ipairs(keys) do " +
+                    "if i % 2 == 0 then " +
+                        "local name = ARGV[1] .. v; " +
+                        "size = size + redis.call('memory', 'usage', name); " +
+                    "end;" +
+                "end; " +
+                "return size; ", Arrays.asList(getName()), prefix);
+    }
+
     @Override
     public RLock getFairLock(K key) {
         String lockName = getLockByMapKey(key, "fairlock");

redisson/src/test/java/org/redisson/RedissonListMultimapTest.java

@@ -3,6 +3,7 @@ package org.redisson;
 import org.junit.Test;
 import org.redisson.api.RList;
 import org.redisson.api.RListMultimap;
+import org.redisson.api.RSetMultimap;
 
 import java.io.Serializable;
 import java.util.*;
@@ -113,6 +114,16 @@ public class RedissonListMultimapTest extends BaseTest {
 
     }
 
+    @Test
+    public void testSizeInMemory() {
+        RListMultimap<String, String> list = redisson.getListMultimap("test");
+        list.put("1", "2");
+        assertThat(list.sizeInMemory()).isEqualTo(160);
+
+        list.put("1", "3");
+        assertThat(list.sizeInMemory()).isEqualTo(166);
+    }
+
     @Test
     public void testDelete() {
         RListMultimap<String, String> testList = redisson.getListMultimap( "test" );

redisson/src/test/java/org/redisson/RedissonSetMultimapTest.java

@@ -214,6 +214,15 @@ public class RedissonSetMultimapTest extends BaseTest {
         assertThat(multimap1.keySize()).isEqualTo(0);
     }
 
+    @Test
+    public void testSizeInMemory() {
+        RSetMultimap<String, String> set = redisson.getSetMultimap("test");
+        set.put("1", "2");
+        assertThat(set.sizeInMemory()).isEqualTo(229);
+
+        set.put("1", "3");
+        assertThat(set.sizeInMemory()).isEqualTo(259);
+    }
     
     @Test
     public void testSize() {