Issue title: 3.4-SNAPSHOT, OperationTimeoutException, isOperationExecuting
 Issue body: HZ version: 3.4-SNAPSHOT - commit 5f9180b26e102b162e5ec047b2a5862de94676f5
Using smart clients

Enviroment
10 node cluster on 10 dedicate AWS boxes
20 dedicated Client Boxes,  64 clients per box,  Total of 1280 clients

Test
StringMapTest,
duration 5 mins

as a note, a lot of tests with a higher client load run successfully.  making this exception a rare occurrence

```
failures-2014-10-29__04_03_38.txt
Failure[
   message='Worked ran into an unhandled exception'
   type='Worker exception'
   agentAddress=116.69.203.115
   time=Wed Oct 29 04:06:41 UTC 2014
   workerAddress=116.69.203.115:5701
   workerId=worker-+1-229-581-4564-server
   test=TestCase{
          id=stringMap
        , class=com.hazelcast.stabilizer.tests.map.StringMapTest
        , probe-throughput=throughput
    }
   cause=com.hazelcast.core.OperationTimeoutException: No response for 120000 ms. Aborting invocation! BasicInvocationFuture{invocation=BasicInvocation{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=207, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[116.69.203.115]:5701}, done=false} Not all backups have completed  backups-expected:0 backups-completed: 1
    at com.hazelcast.spi.impl.BasicInvocationFuture.newOperationTimeoutException(BasicInvocationFuture.java:272)
    at com.hazelcast.spi.impl.BasicInvocationFuture.waitForResponse(BasicInvocationFuture.java:233)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:180)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)
    at ------ End remote and begin local stack-trace ------.(Unknown Source)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponse(BasicInvocationFuture.java:356)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponseOrThrowException(BasicInvocationFuture.java:289)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:181)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)

]
Failure[
   message='Worked ran into an unhandled exception'
   type='Worker exception'
   agentAddress=116.69.203.115
   time=Wed Oct 29 04:07:35 UTC 2014
   workerAddress=116.69.203.115:5701
   workerId=worker-+1-229-581-4564-server
   test=TestCase{
          id=stringMap
        , class=com.hazelcast.stabilizer.tests.map.StringMapTest
        , probe-throughput=throughput
    }
   cause=com.hazelcast.core.OperationTimeoutException: No response for 120000 ms. Aborting invocation! BasicInvocationFuture{invocation=BasicInvocation{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=150, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[116.69.203.115]:5701}, done=false} Not all backups have completed  backups-expected:0 backups-completed: 0
    at com.hazelcast.spi.impl.BasicInvocationFuture.newOperationTimeoutException(BasicInvocationFuture.java:272)
    at com.hazelcast.spi.impl.BasicInvocationFuture.waitForResponse(BasicInvocationFuture.java:233)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:180)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)
    at ------ End remote and begin local stack-trace ------.(Unknown Source)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponse(BasicInvocationFuture.java:356)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponseOrThrowException(BasicInvocationFuture.java:289)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:181)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)

]
```

From the logs of worker-+1-229-581-4564-server

```
WARN  2014-10-29 04:07:30,360 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] No response for 120000 ms. BasicInvocationFuture{invocation=BasicInvocatio
n{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=150, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.154.25
1.78]:5701}, done=false}
WARN  2014-10-29 04:07:30,361 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] Asking if operation execution has been started: BasicInvocationFuture{invo
cation=BasicInvocation{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=150, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, tar
get=Address[116.69.203.115]:5701}, done=false}
WARN  2014-10-29 04:07:35,363 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] While asking 'is-executing': BasicInvocationFuture{invocation=BasicInvocat
ion{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=150, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.154.
251.78]:5701}, done=false}
java.util.concurrent.TimeoutException: Call BasicInvocation{ serviceName='hz:impl:mapService', op=com.hazelcast.spi.impl.IsStillExecutingOperation@2f97c868, partitionId=-1, replicaIndex=0, tryCount=0,
 tryPauseMillis=0, invokeCount=1, callTimeout=5000, target=Address[116.69.203.115]:5701} encountered a timeout
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponse(BasicInvocationFuture.java:321)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponseOrThrowException(BasicInvocationFuture.java:289)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:181)
    at com.hazelcast.spi.impl.BasicInvocationFuture.isOperationExecuting(BasicInvocationFuture.java:390)
    at com.hazelcast.spi.impl.BasicInvocationFuture.waitForResponse(BasicInvocationFuture.java:228)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:180)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)
WARN  2014-10-29 04:07:35,365 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] 'is-executing': false -> BasicInvocationFuture{invocation=BasicInvocation{
 serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=150, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.154.251.
78]:5701}, done=false}
```

From the logs of worker-+1-229-581-4564-server

```
WARN  2014-10-29 04:06:36,024 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] No response for 120000 ms. BasicInvocationFuture{invocation=BasicInvocati
on{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=207, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.180.4
9.47]:5701}, done=false}
WARN  2014-10-29 04:06:36,025 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] Asking if operation execution has been started: BasicInvocationFuture{inv
ocation=BasicInvocation{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=207, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, ta
rget=Address[116.69.203.115]:5701}, done=false}
WARN  2014-10-29 04:06:41,028 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] While asking 'is-executing': BasicInvocationFuture{invocation=BasicInvoca
tion{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=207, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.180
.49.47]:5701}, done=false}
java.util.concurrent.TimeoutException: Call BasicInvocation{ serviceName='hz:impl:mapService', op=com.hazelcast.spi.impl.IsStillExecutingOperation@1dc39fc3, partitionId=-1, replicaIndex=0, tryCount=0,
 tryPauseMillis=0, invokeCount=1, callTimeout=5000, target=Address[116.69.203.115]:5701} encountered a timeout
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponse(BasicInvocationFuture.java:321)
    at com.hazelcast.spi.impl.BasicInvocationFuture.resolveApplicationResponseOrThrowException(BasicInvocationFuture.java:289)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:181)
    at com.hazelcast.spi.impl.BasicInvocationFuture.isOperationExecuting(BasicInvocationFuture.java:390)
    at com.hazelcast.spi.impl.BasicInvocationFuture.waitForResponse(BasicInvocationFuture.java:228)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:180)
    at com.hazelcast.spi.impl.BasicInvocationFuture.get(BasicInvocationFuture.java:160)
    at com.hazelcast.map.impl.proxy.MapProxySupport.invokeOperation(MapProxySupport.java:404)
    at com.hazelcast.map.impl.proxy.MapProxySupport.putInternal(MapProxySupport.java:365)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:102)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.put(MapProxyImpl.java:89)
    at com.hazelcast.stabilizer.tests.map.StringMapTest.warmup(StringMapTest.java:102)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.TestContainer.invoke(TestContainer.java:177)
    at com.hazelcast.stabilizer.worker.TestContainer.localWarmup(TestContainer.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.hazelcast.stabilizer.worker.MemberWorker$TestCommandRequestProcessingThread$2.doRun(MemberWorker.java:444)
    at com.hazelcast.stabilizer.worker.MemberWorker$CommandThread.run(MemberWorker.java:535)
WARN  2014-10-29 04:06:41,030 [Thread-5] com.hazelcast.spi.impl.BasicInvocation: [116.69.203.115]:5701 [workers] [3.4-SNAPSHOT] 'is-executing': false -> BasicInvocationFuture{invocation=BasicInvocation
{ serviceName='hz:impl:mapService', op=PutOperation{stringmap-stringMap}, partitionId=207, replicaIndex=0, tryCount=250, tryPauseMillis=500, invokeCount=1, callTimeout=60000, target=Address[10.180.49.
47]:5701}, done=false}
```

could not find any " com.hazelcast.util.HealthMonitor:"  statements logged in any logs.

 Comments: 
 Comment 0: Full Logs   This is a public link https://s3.amazonaws.com/stabilizer/issues3951/timeout.zip

 Comment 1: @gurbuzali, why such issue should be added into 3.4.1 milestone, could it not be resolved in 3.4 as 3.4 is going to be released this end of month ? we're caring about any issue related to performance or stability and thanks for caring about this.

 Comment 2: 3.4 stabilizer tests passed. If you experience again; then reopen.

{'source': 'GithubIssues', 'repo_name_with_owner': 'hazelcast/hazelcast', 'issue_id': 47289872, 'repo_stars': 5091.0}