diff --git a/redisson/src/main/java/org/redisson/RedissonKeys.java b/redisson/src/main/java/org/redisson/RedissonKeys.java
index 3361b8ce021..1aae2191273 100644
--- a/redisson/src/main/java/org/redisson/RedissonKeys.java
+++ b/redisson/src/main/java/org/redisson/RedissonKeys.java
@@ -23,7 +23,6 @@
 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.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
@@ -207,7 +206,7 @@ public RFuture<Long> deleteByPatternAsync(final String pattern) {
         final RPromise<Long> result = commandExecutor.getConnectionManager().newPromise();
         final AtomicReference<Throwable> failed = new AtomicReference<Throwable>();
         final AtomicLong count = new AtomicLong();
-        Set<MasterSlaveEntry> entries = commandExecutor.getConnectionManager().getEntrySet();
+        Collection<MasterSlaveEntry> entries = commandExecutor.getConnectionManager().getEntrySet();
         final AtomicLong executed = new AtomicLong(entries.size());
         final FutureListener<Long> listener = new FutureListener<Long>() {
             @Override
@@ -301,14 +300,13 @@ private RFuture<Long> executeAsync(RedisStrictCommand<Long> command, String ...
         Map<MasterSlaveEntry, List<String>> range2key = new HashMap<MasterSlaveEntry, List<String>>();
         for (String key : keys) {
             int slot = commandExecutor.getConnectionManager().calcSlot(key);
-            for (MasterSlaveEntry entry : commandExecutor.getConnectionManager().getEntrySet()) {
-                List<String> list = range2key.get(entry);
-                if (list == null) {
-                    list = new ArrayList<String>();
-                    range2key.put(entry, list);
-                }
-                list.add(key);
+            MasterSlaveEntry entry = commandExecutor.getConnectionManager().getEntry(slot);
+            List<String> list = range2key.get(entry);
+            if (list == null) {
+                list = new ArrayList<String>();
+                range2key.put(entry, list);
             }
+            list.add(key);
         }
 
         final RPromise<Long> result = commandExecutor.getConnectionManager().newPromise();
diff --git a/redisson/src/main/java/org/redisson/cluster/ClusterConnectionManager.java b/redisson/src/main/java/org/redisson/cluster/ClusterConnectionManager.java
index bb3e7d3521a..4eb0a1977b6 100644
--- a/redisson/src/main/java/org/redisson/cluster/ClusterConnectionManager.java
+++ b/redisson/src/main/java/org/redisson/cluster/ClusterConnectionManager.java
@@ -568,8 +568,8 @@ private void checkSlotsChange(ClusterServersConfig cfg, Collection<ClusterPartit
         }
 
         for (Integer slot : removedSlots) {
-            MasterSlaveEntry entry = removeMaster(slot);
-            entry.removeSlotRange(slot);
+            MasterSlaveEntry entry = getEntry(slot);
+            removeMaster(slot);
             if (entry.getSlotRanges().isEmpty()) {
                 entry.shutdownMasterAsync();
                 log.info("{} master and slaves for it removed", entry.getClient().getAddr());
@@ -584,12 +584,11 @@ private void checkSlotsChange(ClusterServersConfig cfg, Collection<ClusterPartit
         }
         for (final Integer slot : addedSlots) {
             ClusterPartition partition = find(newPartitions, slot);
-            for (MasterSlaveEntry entry : getEntrySet()) {
-                if (entry.getClient().getAddr().equals(partition.getMasterAddr())) {
-                    addEntry(slot, entry);
-                    lastPartitions.put(slot, partition);
-                    break;
-                }
+            MasterSlaveEntry entry = getEntry(partition.getMasterAddr());
+            if (entry != null && entry.getClient().getAddr().equals(partition.getMasterAddr())) {
+                addEntry(slot, entry);
+                lastPartitions.put(slot, partition);
+                break;
             }
         }
     }
@@ -611,7 +610,6 @@ private void checkSlotsMigration(Collection<ClusterPartition> newPartitions, Str
                 MasterSlaveEntry entry = getEntry(currentPartition.getMasterAddr());
 
                 for (Integer slot : addedSlots) {
-                    entry.addSlotRange(slot);
                     addEntry(slot, entry);
                     lastPartitions.put(slot, currentPartition);
                 }
@@ -623,7 +621,6 @@ private void checkSlotsMigration(Collection<ClusterPartition> newPartitions, Str
                 removedSlots.removeAll(newPartition.getSlots());
                 for (Integer removeSlot : removedSlots) {
                     if (lastPartitions.remove(removeSlot, currentPartition)) {
-                        entry.removeSlotRange(removeSlot);
                         removeMaster(removeSlot);
                     }
                 }
diff --git a/redisson/src/main/java/org/redisson/command/CommandAsyncService.java b/redisson/src/main/java/org/redisson/command/CommandAsyncService.java
index 784d6a278f3..cadcecefd0a 100644
--- a/redisson/src/main/java/org/redisson/command/CommandAsyncService.java
+++ b/redisson/src/main/java/org/redisson/command/CommandAsyncService.java
@@ -16,11 +16,13 @@
 package org.redisson.command;
 
 import java.net.InetSocketAddress;
+import java.util.AbstractMap;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -71,9 +73,6 @@
 import io.netty.util.TimerTask;
 import io.netty.util.concurrent.Future;
 import io.netty.util.concurrent.FutureListener;
-import java.util.AbstractMap;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 
 /**
  *
@@ -198,7 +197,7 @@ public <T, R> RFuture<R> readAsync(InetSocketAddress client, String key, Codec c
     @Override
     public <T, R> RFuture<Collection<R>> readAllAsync(RedisCommand<T> command, Object... params) {
         final RPromise<Collection<R>> mainPromise = connectionManager.newPromise();
-        final Set<MasterSlaveEntry> nodes = connectionManager.getEntrySet();
+        final Collection<MasterSlaveEntry> nodes = connectionManager.getEntrySet();
         final List<R> results = new ArrayList<R>();
         final AtomicInteger counter = new AtomicInteger(nodes.size());
         FutureListener<R> listener = new FutureListener<R>() {
@@ -288,7 +287,7 @@ public <R, T> RFuture<R> readAllAsync(RedisCommand<T> command, SlotCallback<T, R
 
     private <T, R> RFuture<R> allAsync(boolean readOnlyMode, RedisCommand<T> command, final SlotCallback<T, R> callback, Object... params) {
         final RPromise<R> mainPromise = connectionManager.newPromise();
-        final Set<MasterSlaveEntry> nodes = connectionManager.getEntrySet();
+        final Collection<MasterSlaveEntry> nodes = connectionManager.getEntrySet();
         final AtomicInteger counter = new AtomicInteger(nodes.size());
         FutureListener<T> listener = new FutureListener<T>() {
             @Override
@@ -413,7 +412,7 @@ public <T, R> RFuture<R> evalWriteAllAsync(RedisCommand<T> command, SlotCallback
 
     public <T, R> RFuture<R> evalAllAsync(boolean readOnlyMode, RedisCommand<T> command, final SlotCallback<T, R> callback, String script, List<Object> keys, Object... params) {
         final RPromise<R> mainPromise = connectionManager.newPromise();
-        final Set<MasterSlaveEntry> entries = connectionManager.getEntrySet();
+        final Collection<MasterSlaveEntry> entries = connectionManager.getEntrySet();
         final AtomicInteger counter = new AtomicInteger(entries.size());
         FutureListener<T> listener = new FutureListener<T>() {
 
diff --git a/redisson/src/main/java/org/redisson/connection/ConnectionManager.java b/redisson/src/main/java/org/redisson/connection/ConnectionManager.java
index 6a6ee051753..b89edb115fe 100644
--- a/redisson/src/main/java/org/redisson/connection/ConnectionManager.java
+++ b/redisson/src/main/java/org/redisson/connection/ConnectionManager.java
@@ -18,7 +18,6 @@
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.util.Collection;
-import java.util.Set;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.TimeUnit;
 
@@ -85,7 +84,7 @@ public interface ConnectionManager {
 
     Codec getCodec();
 
-    Set<MasterSlaveEntry> getEntrySet();
+    Collection<MasterSlaveEntry> getEntrySet();
     
     MasterSlaveEntry getEntry(int slot);
     
diff --git a/redisson/src/main/java/org/redisson/connection/MasterSlaveConnectionManager.java b/redisson/src/main/java/org/redisson/connection/MasterSlaveConnectionManager.java
index 5918060b9ad..69e357742aa 100644
--- a/redisson/src/main/java/org/redisson/connection/MasterSlaveConnectionManager.java
+++ b/redisson/src/main/java/org/redisson/connection/MasterSlaveConnectionManager.java
@@ -24,9 +24,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Map.Entry;
 import java.util.Queue;
-import java.util.Set;
 import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ExecutorService;
@@ -130,7 +128,8 @@ public boolean cancel() {
     
     protected MasterSlaveServersConfig config;
 
-    private final Map<Integer, MasterSlaveEntry> entries = PlatformDependent.newConcurrentHashMap();
+    private final Map<Integer, MasterSlaveEntry> slot2entry = PlatformDependent.newConcurrentHashMap();
+    private final Map<InetSocketAddress, MasterSlaveEntry> addr2entry = PlatformDependent.newConcurrentHashMap();
 
     private final RPromise<Boolean> shutdownPromise;
 
@@ -234,8 +233,9 @@ public Codec getCodec() {
         return codec;
     }
 
-    public Set<MasterSlaveEntry> getEntrySet() {
-        return new HashSet<MasterSlaveEntry>(entries.values());
+    @Override
+    public Collection<MasterSlaveEntry> getEntrySet() {
+        return addr2entry.values();
     }
     
     protected void initTimer(MasterSlaveServersConfig config) {
@@ -672,29 +672,34 @@ public boolean onStatus(PubSubType type, String channel) {
 
     @Override
     public MasterSlaveEntry getEntry(InetSocketAddress addr) {
-        // TODO optimize
-        for (Entry<Integer, MasterSlaveEntry> entry : entries.entrySet()) {
-            if (entry.getValue().getClient().getAddr().equals(addr)) {
-                return entry.getValue();
-            }
-        }
-        return null;
+        return addr2entry.get(addr);
     }
 
+    @Override
     public MasterSlaveEntry getEntry(int slot) {
-        return entries.get(slot);
+        return slot2entry.get(slot);
     }
     
-    protected void changeMaster(int slot, URI address) {
-        getEntry(slot).changeMaster(address);
+    protected final void changeMaster(int slot, URI address) {
+        MasterSlaveEntry entry = getEntry(slot);
+        addr2entry.remove(entry.getClient().getAddr());
+        entry.changeMaster(address);
+        addr2entry.put(entry.getClient().getAddr(), entry);
     }
 
-    protected void addEntry(Integer slot, MasterSlaveEntry entry) {
-        entries.put(slot, entry);
+    protected final void addEntry(Integer slot, MasterSlaveEntry entry) {
+        slot2entry.put(slot, entry);
+        entry.addSlotRange(slot);
+        addr2entry.put(entry.getClient().getAddr(), entry);
     }
 
     protected MasterSlaveEntry removeMaster(Integer slot) {
-        return entries.remove(slot);
+        MasterSlaveEntry entry = slot2entry.remove(slot);
+        entry.removeSlotRange(slot);
+        if (entry.getSlotRanges().isEmpty()) {
+            addr2entry.remove(entry.getClient().getAddr());
+        }
+        return entry;
     }
 
     @Override
@@ -812,7 +817,7 @@ public void shutdown(long quietPeriod, long timeout, TimeUnit unit) {
         shutdownPromise.trySuccess(true);
         shutdownLatch.awaitUninterruptibly();
 
-        for (MasterSlaveEntry entry : entries.values()) {
+        for (MasterSlaveEntry entry : getEntrySet()) {
             entry.shutdown();
         }