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https://issues.apache.org/jira/browse/DIRMINA-764?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13164962#comment-13164962
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Max Ng commented on DIRMINA-764:
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I am implementing a TCP server with 2.0.4 and runs into the same problem (a lot 
of reads, very few writes, OutOfMemoryError eventually). I am running Java 
1.6.0_29 on OS X Lion. Will this be fixed in 2.0.5?

If I want to throttle reads manually, what is the recommended approach? I would 
like to suspend all reads when memory usage exceed a threshold, forcing TCP 
flow control to kick in and stop the client from sending more data. Can 
IoEventQueueThrottle be used for this purpose? What does the threshold 
parameter in its constructor mean?
                
> DDOS possible in only a few seconds...
> --------------------------------------
>
>                 Key: DIRMINA-764
>                 URL: https://issues.apache.org/jira/browse/DIRMINA-764
>             Project: MINA
>          Issue Type: Bug
>    Affects Versions: 2.0.0-RC1
>            Reporter: Emmanuel Lecharny
>            Assignee: Emmanuel Lecharny
>            Priority: Blocker
>             Fix For: 2.0.5
>
>         Attachments: screenshot-1.jpg, screenshot-2.jpg
>
>
> We can kill a server in just a few seconds using the stress test found in 
> DIRMINA-762.
> If we inject messages with no delay, using 50 threads to do that, the 
> ProtocolCodecFilter$MessageWriteRequest is stuffed with hundred of thousands 
> messages waiting to be written back to the client, with no success.
> On the client side, we receive almost no messages :
> 0 messages/sec (total messages received 1)
> 2 messages/sec (total messages received 11)
> 8 messages/sec (total messages received 55)
> 8 messages/sec (total messages received 95)
> 9 messages/sec (total messages received 144)
> 3 messages/sec (total messages received 162)
> 1 messages/sec (total messages received 169)
> ...
> On the server side, the memory is totally swamped in 20 seconds, with no way 
> to recover :
> Exception in thread "pool-1-thread-1" java.lang.OutOfMemoryError: Java heap 
> space
> (see graph attached)
> On the server, ConcurrentLinkedQueue contain the messages to be written (in 
> my case, 724 499 Node are present). There are also 361629 
> DefaultWriteRequests, 361628 DefaultWriteFutures, 361625 SimpleBuffer, 361 
> 618 ProtocolCodecFilter$MessageWriteRequest and 361 614 
> ProtocolCodecFilter$EncodedWriteRequests.
> That mean we don't flush them to the client at all. 

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