diff --git a/cluster2/src/main/java/io/scalecube/cluster2/gossip/Gossip.java b/cluster2/src/main/java/io/scalecube/cluster2/gossip/Gossip.java
index 516b4ce6..90af588c 100644
--- a/cluster2/src/main/java/io/scalecube/cluster2/gossip/Gossip.java
+++ b/cluster2/src/main/java/io/scalecube/cluster2/gossip/Gossip.java
@@ -37,10 +37,6 @@ public Gossip(UUID gossiperId, long sequenceId, byte[] message, long infectionPe
     this.infectionPeriod = infectionPeriod;
   }
 
-  public String gossipId() {
-    return gossiperId + "-" + sequenceId;
-  }
-
   public UUID gossiperId() {
     return gossiperId;
   }
diff --git a/cluster2/src/main/java/io/scalecube/cluster2/gossip/GossipProtocol.java b/cluster2/src/main/java/io/scalecube/cluster2/gossip/GossipProtocol.java
index 6b6c2402..c94ba1d1 100644
--- a/cluster2/src/main/java/io/scalecube/cluster2/gossip/GossipProtocol.java
+++ b/cluster2/src/main/java/io/scalecube/cluster2/gossip/GossipProtocol.java
@@ -15,12 +15,13 @@
 import io.scalecube.cluster2.sbe.MessageHeaderDecoder;
 import java.time.Duration;
 import java.util.ArrayList;
-import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.UUID;
 import java.util.function.Supplier;
 import org.agrona.MutableDirectBuffer;
+import org.agrona.collections.ArrayListUtil;
+import org.agrona.collections.IntArrayList;
 import org.agrona.collections.Object2ObjectHashMap;
 import org.agrona.concurrent.EpochClock;
 import org.agrona.concurrent.UnsafeBuffer;
@@ -44,11 +45,11 @@ public class GossipProtocol extends AbstractAgent {
   private long currentPeriod = 0;
   private long gossipCounter = 0;
   private final Map<UUID, SequenceIdCollector> sequenceIdCollectors = new Object2ObjectHashMap<>();
-  private final Map<String, Gossip> gossips = new Object2ObjectHashMap<>();
-  private final List<Member> remoteMembers = new ArrayList<>();
-  private final List<Member> gossipMembers = new ArrayList<>();
-  private final List<Gossip> gossipsToSend = new ArrayList<>();
-  private final List<String> gossipsToRemove = new ArrayList<>();
+  private final ArrayList<Gossip> gossips = new ArrayList<>();
+  private final ArrayList<Member> remoteMembers = new ArrayList<>();
+  private final ArrayList<Member> gossipMembers = new ArrayList<>();
+  private final IntArrayList gossipsToSend = new IntArrayList();
+  private final IntArrayList gossipsToRemove = new IntArrayList();
 
   public GossipProtocol(
       Transport transport,
@@ -87,16 +88,19 @@ protected void onTick() {
 
     nextGossipMembers();
 
-    for (int i = 0, n = gossipMembers.size(); i < n; i++) {
-      spreadGossips(period, gossipMembers.get(i));
+    for (int n = gossipMembers.size() - 1, i = n; i >= 0; i--) {
+      final Member member = gossipMembers.get(i);
+      ArrayListUtil.fastUnorderedRemove(gossipMembers, i);
+      spreadGossips(period, member);
     }
 
     // Sweep gossips
 
     nextGossipsToRemove(period);
 
-    for (int i = 0, n = gossipsToRemove.size(); i < n; i++) {
-      gossips.remove(gossipsToRemove.get(i));
+    for (int n = gossipsToRemove.size() - 1, i = n; i >= 0; i--) {
+      final int index = gossipsToRemove.fastUnorderedRemove(i);
+      ArrayListUtil.fastUnorderedRemove(gossips, index);
     }
   }
 
@@ -124,9 +128,10 @@ private void nextGossipsToRemove(long period) {
     final int periodsToSweep =
         ClusterMath.gossipPeriodsToSweep(config.gossipRepeatMult(), remoteMembers.size() + 1);
 
-    for (final Gossip gossip : gossips.values()) {
+    for (int i = 0, n = gossips.size(); i < n; i++) {
+      final Gossip gossip = gossips.get(i);
       if (period > gossip.infectionPeriod() + periodsToSweep) {
-        gossipsToRemove.add(gossip.gossipId());
+        gossipsToRemove.addInt(i);
       }
     }
   }
@@ -150,8 +155,8 @@ private void spreadGossips(long period, Member member) {
     final String address = member.address();
     final UUID from = localMember.id();
 
-    for (int i = 0, n = gossipsToSend.size(); i < n; i++) {
-      final Gossip gossip = gossipsToSend.get(i);
+    for (int n = gossipsToSend.size() - 1, i = n; i >= 0; i--) {
+      final Gossip gossip = gossips.get(gossipsToSend.fastUnorderedRemove(i));
       transport.send(
           address, gossipRequestCodec.encode(from, gossip), 0, gossipRequestCodec.encodedLength());
     }
@@ -163,9 +168,10 @@ private void nextGossipsToSend(long period, Member member) {
     final int periodsToSpread =
         ClusterMath.gossipPeriodsToSpread(config.gossipRepeatMult(), remoteMembers.size() + 1);
 
-    for (final Gossip gossip : gossips.values()) {
+    for (int i = 0, n = gossips.size(); i < n; i++) {
+      final Gossip gossip = gossips.get(i);
       if (gossip.infectionPeriod() + periodsToSpread >= period && !gossip.isInfected(member.id())) {
-        gossipsToSend.add(gossip);
+        gossipsToSend.addInt(i);
       }
     }
   }
@@ -197,10 +203,8 @@ private void onGossipMessage(GossipMessageDecoder decoder) {
     final byte[] message = new byte[messageLength];
     decoder.getMessage(message, 0, messageLength);
 
-    final Gossip gossip = new Gossip(localMember.id(), sequenceId, message, period);
-
-    gossips.put(gossip.gossipId(), gossip);
-    ensureSequence(localMember.id()).add(gossip.sequenceId());
+    gossips.add(new Gossip(localMember.id(), sequenceId, message, period));
+    ensureSequence(localMember.id()).add(sequenceId);
   }
 
   private void onGossipRequest(GossipRequestDecoder decoder) {
@@ -217,13 +221,12 @@ private void onGossipRequest(GossipRequestDecoder decoder) {
     final byte[] message = new byte[messageLength];
     gossipDecoder.getMessage(message, 0, messageLength);
 
-    final String gossipId = gossiperId + "-" + sequenceId;
-    Gossip gossip = gossips.get(gossipId);
+    Gossip gossip = getGossip(gossiperId, sequenceId);
 
     if (ensureSequence(gossiperId).add(sequenceId)) {
       if (gossip == null) { // new gossip
         gossip = new Gossip(gossiperId, sequenceId, message, period);
-        gossips.put(gossipId, gossip);
+        gossips.add(gossip);
         emitGossipMessage(message);
       }
     }
@@ -233,6 +236,18 @@ private void onGossipRequest(GossipRequestDecoder decoder) {
     }
   }
 
+  private Gossip getGossip(UUID gossiperId, long sequenceId) {
+    Gossip result = null;
+    for (int n = gossips.size(), i = 0; i < n; i++) {
+      final Gossip gossip = gossips.get(i);
+      if (gossip.gossiperId() == gossiperId && gossip.sequenceId() == sequenceId) {
+        result = gossip;
+        break;
+      }
+    }
+    return result;
+  }
+
   private void emitGossipMessage(byte[] message) {
     unsafeBuffer.wrap(message);
     messageTx.transmit(1, unsafeBuffer, 0, unsafeBuffer.capacity());