There is not memory leak. Your memory graph show that memory not active using. Likely you use a big object\map\etc in memory. GC don't stop working because level of free memory is low. You need to extra memory or change GC trigger.

2016-04-11 7:31 GMT+03:00 sam mohel <>:

​@spico there is what i got after ruuning code again in local mode , how can i know if there is memory leak or not ?

On Fri, Apr 8, 2016 at 1:45 AM, sam mohel <> wrote:
sorry it's supposed to use hashmap.remove() to not to make it reach to heapsize  right !

On Fri, Apr 8, 2016 at 1:43 AM, sam mohel <> wrote:
Really thanks for your patience , what i got about hashmap you mentioned that it's supposed not to use hashmap.remove();
Right ?

On Thu, Apr 7, 2016 at 10:45 AM, Spico Florin <> wrote:
  By release the hashmap, I mean that you need to remove the keys at some points. Meaning hashMap.remove(key). If you just use hashMap.put() in the nextTuple method of the spout or in the execute method of the bolt, and never use the hashMap.remove() and your hashMap is a field in the Bolt or Spout class, then your map will grow and you'll reach your heap Size. 
 The issue that yo have with the jvisualvm is that you have installed only the Java Runtime Evironment (only the java vm) but not the the JDK (Java Development Kit) . Please install the JDK. 
After installing look at hashmap classes. Check the memory size for them. Run GC and check if the memort size for them grows. If they grow even after GC then you could have a memory leak.

I hope that it helps.

On Wed, Apr 6, 2016 at 8:49 AM, sam mohel <> wrote:
i used this command  java -XX:+PrintFlagsFinal -version | grep HeapSize
and got

uintx ErgoHeapSizeLimit                         = 0               {product}          
    uintx HeapSizePerGCThread                       = 87241520        {product}          
    uintx InitialHeapSize                          := 63056640        {product}          
    uintx LargePageHeapSizeThreshold                = 134217728       {product}          
    uintx MaxHeapSize                              := 1010827264      {product}

On Wed, Apr 6, 2016 at 12:44 AM, sam mohel <> wrote:
sorry i forgot to mention that my ram is 3.8 GB and i used hahsmap in the code but i don't know what do you mean by release it ?

On Wed, Apr 6, 2016 at 12:20 AM, sam mohel <> wrote:
@ florin thanks for replying , i installed tool but got when i ran it
i checked update-alternatives --config java
There are 3 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
  0            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1071      auto mode
* 1            /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java   1061      manual mode
  2            /usr/lib/jvm/java-6-oracle/jre/bin/java          1062      manual mode
  3            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1071      manual mode

On Sun, Apr 3, 2016 at 9:19 PM, Spico Florin <> wrote:
before increasing the ram (by rpoviding in command line arguments the jvm options java -Xmx) try to use a profile tool such as jvisualvm jprobe to see if you have amemory leak. do you use a cache (for example hashmap where you store some data but never relese it). how much ram do you have on your machine? check your default heap size with the help of this link
regards florin

On Sunday, April 3, 2016, sam mohel <> wrote:
> do you mean in storm.yaml ? or where ?
> On Sun, Apr 3, 2016 at 11:56 AM, Andrey Dudin <> wrote:
>> Try to extra more RAM for this topology.
>> -Xms and -Xmx options
>> 2016-04-03 1:32 GMT+03:00 sam mohel <>:
>>> i'm facing problem with topology i ran it in local mode and got
>>> Async loop died!java.lang.OutOfMemoryError: GC overhead limit exceeded
>>> Can you help on this ? if there is any data you need for helping just tell me
>>> Thanks in advance
>> --
>> С уважением Дудин Андрей

С уважением Дудин Андрей