You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@activemq.apache.org by Lyubov Romanchuk <lu...@checkpoint.com> on 2014/06/29 16:16:08 UTC
[ActiveMQCPP 3.8.2|Linux] crash in
activemq::core::ConnectionAudit::isDuplicate
Hi,
We use activemqcpp library from the version 3.8.2.
Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
Could you please advise with this core - what may cause such crash, is it a known issue?
Here is the call stack from one of the cores:
* 1 Thread 32129 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
(gdb) bt
#0 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
#1 0x76108cad in std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> >, std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > >, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find (this=0x874ce14, __k=...) at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
#2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
#3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at decaf/util/StlMap.h:794
#4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0x32332d46, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
#5 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0xc0a7e88, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
#6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
#7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
#8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
#9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at decaf/lang/Thread.cpp:141
#10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
#11 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
#12 0x757f145b in start_thread () from /lib/libpthread.so.0
#13 0x7566024e in clone () from /lib/libc.so.6
(gdb) t 10
[Switching to thread 10 (Thread 32093)]#0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
(gdb) bt
#0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
#1 0x0849cd55 in _Unwind_Find_FDE ()
#2 0x0849a815 in ?? ()
#3 0x0849b0a8 in _Unwind_RaiseException ()
#4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
#5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
#6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at decaf/lang/Pointer.h:258
#7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0xb726488, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
#8 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0x4ff94730, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
#9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
#10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
#11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
#12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at decaf/lang/Thread.cpp:141
#13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:266
#14 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
#15 0x757f145b in start_thread () from /lib/libpthread.so.0
#16 0x7566024e in clone () from /lib/libc.so.6
Best regards,
Lyuba
Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
Posted by Timothy Bish <ta...@gmail.com>.
On 07/02/2014 04:19 AM, Lyubov Romanchuk wrote:
> Ok. But this function doesn't only check for duplicates it changes the members as well.
> And it means that ConnectionAudit::isDuplicate must be thread safe because may be called from different threads and as I see it's not.
>
>
> Software Developer | Check Point Software Technologies Ltd.
>
> ( Phone: +972 73 2264585
> * Email: lubar@checkpoint.com
> , Address: Ha'solelim 5 St. Tel Aviv 67897, Israel
>
>
> -----Original Message-----
> From: Timothy Bish [mailto:tabish121@gmail.com]
> Sent: Tuesday, July 01, 2014 6:23 PM
> To: dev@activemq.apache.org
> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
>
> On 07/01/2014 11:18 AM, Lyubov Romanchuk wrote:
>> But what is the purpose of checkForDuplicates? And which functionality will be disabled in case it's false.
>>
> Surprisingly it checks for duplicates and filter them out in cases where your client might receive a duplicate message from the broker such as failover disconnect / reconnect.
>
>> -----Original Message-----
>> From: Timothy Bish [mailto:tabish121@gmail.com]
>> Sent: Tuesday, July 01, 2014 6:08 PM
>> To: dev@activemq.apache.org
>> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
>> activemq::core::ConnectionAudit::isDuplicate
>>
>> On 07/01/2014 10:37 AM, Lyubov Romanchuk wrote:
>>> Hi,
>>>
>>> Thank you for the response.
>>> 1) It's very hard to support the test case for reproduction of this
>>> issue because I don't know the root cause of the core and we have
>>> too complicated environment in order to try to simulate this
>>> behaviour
>>> 2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
>>> 3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
>>>
>>> Best regards,
>>> Lyuba
>>>
>>> -----Original Message-----
>>> From: Timothy Bish [mailto:tabish121@gmail.com]
>>> Sent: Tuesday, July 01, 2014 12:20 AM
>>> To: dev@activemq.apache.org
>>> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
>>> activemq::core::ConnectionAudit::isDuplicate
>>>
>>> On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
>>>> Hi,
>>>> We use activemqcpp library from the version 3.8.2.
>>>> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
>>>> Could you please advise with this core - what may cause such crash, is it a known issue?
>>>>
>>>> Here is the call stack from one of the cores:
>>>>
>>>> * 1 Thread 32129 0x760417ab in
>>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>>> (gdb) bt
>>>> #0 0x760417ab in
>>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>>> #1 0x76108cad in
>>>> std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDesti
>>>> n ation, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>>> std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestinati
>>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter> const,
>>>> decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>>> decaf::util::concurrent::atomic::AtomicRefCounter> >,
>>>> std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::A
>>>> c tiveMQDestination,
>>>> decaf::util::concurrent::atomic::AtomicRefCounter>
>>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>>> decaf::util::concurrent::atomic::AtomicRefCounter> > >,
>>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>>> std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::Ac
>>>> t iveMQDestination,
>>>> decaf::util::concurrent::atomic::AtomicRefCounter>
>>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>>> decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find
>>>> (this=0x874ce14, __k=...) at
>>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
>>>> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
>>>> at
>>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
>>>> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate
>>>> (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at
>>>> decaf/util/StlMap.h:794
>>>> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>>> (this=0x8a74408, dispatcher=0x32332d46, message=...) at
>>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>>> #5 0x76141bb5 in
>>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>>> (this=0xc0a7e88, dispatch=...) at
>>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>>> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>>> (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
>>>> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>>> (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>>> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>>> (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
>>>> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at
>>>> decaf/lang/Thread.cpp:141
>>>> #10 0x76421c17 in (anonymous namespace)::runCallback
>>>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
>>>> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
>>>> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
>>>> #13 0x7566024e in clone () from /lib/libc.so.6
>>>> (gdb) t 10
>>>> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in
>>>> dl_iterate_phdr () from /lib/libc.so.6
>>>> (gdb) bt
>>>> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>>>> #1 0x0849cd55 in _Unwind_Find_FDE ()
>>>> #2 0x0849a815 in ?? ()
>>>> #3 0x0849b0a8 in _Unwind_RaiseException ()
>>>> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
>>>> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate
>>>> (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
>>>> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate
>>>> (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at
>>>> decaf/lang/Pointer.h:258
>>>> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>>> (this=0x8a74408, dispatcher=0xb726488, message=...) at
>>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>>> #8 0x76141bb5 in
>>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>>> (this=0x4ff94730, dispatch=...) at
>>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>>> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>>> (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
>>>> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>>> (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>>> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>>> (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
>>>> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at
>>>> decaf/lang/Thread.cpp:141
>>>> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8)
>>>> at decaf/internal/util/concurrent/Threading.cpp:266
>>>> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>>> (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
>>>> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
>>>> #16 0x7566024e in clone () from /lib/libc.so.6
>>>>
>>>> Best regards,
>>>> Lyuba
>>>>
>>> No know issue in this area. A test case to reproduce would be helpful.
>>>
>> You can set connection.checkForDuplicates=false on the URI or call
>> factory.setCheckForDuplicates(false) on your ActiveMQConnectionFactory instance to disable duplicate checking which should sort you out.
>>
>> --
>> Tim Bish
>> Sr Software Engineer | RedHat Inc.
>> tim.bish@redhat.com | www.fusesource.com | www.redhat.com
>> skype: tabish121 | twitter: @tabish121
>> blog: http://timbish.blogspot.com/
>>
>>
>>
>> Email secured by Check Point
>>
>
> --
> Tim Bish
> Sr Software Engineer | RedHat Inc.
> tim.bish@redhat.com | www.fusesource.com | www.redhat.com
> skype: tabish121 | twitter: @tabish121
> blog: http://timbish.blogspot.com/
>
>
> Email secured by Check Point
>
We welcome contributions so if you think you've found an issue go ahead
and dive in and see if you can work up a patch and test to cover the
scenario.
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
RE: [ActiveMQCPP 3.8.2|Linux] crash in
activemq::core::ConnectionAudit::isDuplicate
Posted by Lyubov Romanchuk <lu...@checkpoint.com>.
Ok. But this function doesn't only check for duplicates it changes the members as well.
And it means that ConnectionAudit::isDuplicate must be thread safe because may be called from different threads and as I see it's not.
Software Developer | Check Point Software Technologies Ltd.
( Phone: +972 73 2264585
* Email: lubar@checkpoint.com
, Address: Ha'solelim 5 St. Tel Aviv 67897, Israel
-----Original Message-----
From: Timothy Bish [mailto:tabish121@gmail.com]
Sent: Tuesday, July 01, 2014 6:23 PM
To: dev@activemq.apache.org
Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
On 07/01/2014 11:18 AM, Lyubov Romanchuk wrote:
> But what is the purpose of checkForDuplicates? And which functionality will be disabled in case it's false.
>
Surprisingly it checks for duplicates and filter them out in cases where your client might receive a duplicate message from the broker such as failover disconnect / reconnect.
> -----Original Message-----
> From: Timothy Bish [mailto:tabish121@gmail.com]
> Sent: Tuesday, July 01, 2014 6:08 PM
> To: dev@activemq.apache.org
> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
> activemq::core::ConnectionAudit::isDuplicate
>
> On 07/01/2014 10:37 AM, Lyubov Romanchuk wrote:
>> Hi,
>>
>> Thank you for the response.
>> 1) It's very hard to support the test case for reproduction of this
>> issue because I don't know the root cause of the core and we have
>> too complicated environment in order to try to simulate this
>> behaviour
>> 2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
>> 3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
>>
>> Best regards,
>> Lyuba
>>
>> -----Original Message-----
>> From: Timothy Bish [mailto:tabish121@gmail.com]
>> Sent: Tuesday, July 01, 2014 12:20 AM
>> To: dev@activemq.apache.org
>> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
>> activemq::core::ConnectionAudit::isDuplicate
>>
>> On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
>>> Hi,
>>> We use activemqcpp library from the version 3.8.2.
>>> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
>>> Could you please advise with this core - what may cause such crash, is it a known issue?
>>>
>>> Here is the call stack from one of the cores:
>>>
>>> * 1 Thread 32129 0x760417ab in
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>> (gdb) bt
>>> #0 0x760417ab in
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>> #1 0x76108cad in
>>> std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDesti
>>> n ation, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>> std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestinati
>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter> const,
>>> decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> >,
>>> std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::A
>>> c tiveMQDestination,
>>> decaf::util::concurrent::atomic::AtomicRefCounter>
>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> > >,
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinati
>>> o n, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>> std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::Ac
>>> t iveMQDestination,
>>> decaf::util::concurrent::atomic::AtomicRefCounter>
>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find
>>> (this=0x874ce14, __k=...) at
>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
>>> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
>>> at
>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
>>> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate
>>> (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at
>>> decaf/util/StlMap.h:794
>>> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>> (this=0x8a74408, dispatcher=0x32332d46, message=...) at
>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>> #5 0x76141bb5 in
>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>> (this=0xc0a7e88, dispatch=...) at
>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>> (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
>>> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>> (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>> (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
>>> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at
>>> decaf/lang/Thread.cpp:141
>>> #10 0x76421c17 in (anonymous namespace)::runCallback
>>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
>>> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
>>> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
>>> #13 0x7566024e in clone () from /lib/libc.so.6
>>> (gdb) t 10
>>> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in
>>> dl_iterate_phdr () from /lib/libc.so.6
>>> (gdb) bt
>>> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>>> #1 0x0849cd55 in _Unwind_Find_FDE ()
>>> #2 0x0849a815 in ?? ()
>>> #3 0x0849b0a8 in _Unwind_RaiseException ()
>>> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
>>> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate
>>> (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
>>> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate
>>> (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at
>>> decaf/lang/Pointer.h:258
>>> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>> (this=0x8a74408, dispatcher=0xb726488, message=...) at
>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>> #8 0x76141bb5 in
>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>> (this=0x4ff94730, dispatch=...) at
>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>> (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
>>> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>> (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>> (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
>>> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at
>>> decaf/lang/Thread.cpp:141
>>> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8)
>>> at decaf/internal/util/concurrent/Threading.cpp:266
>>> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>> (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
>>> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
>>> #16 0x7566024e in clone () from /lib/libc.so.6
>>>
>>> Best regards,
>>> Lyuba
>>>
>> No know issue in this area. A test case to reproduce would be helpful.
>>
> You can set connection.checkForDuplicates=false on the URI or call
> factory.setCheckForDuplicates(false) on your ActiveMQConnectionFactory instance to disable duplicate checking which should sort you out.
>
> --
> Tim Bish
> Sr Software Engineer | RedHat Inc.
> tim.bish@redhat.com | www.fusesource.com | www.redhat.com
> skype: tabish121 | twitter: @tabish121
> blog: http://timbish.blogspot.com/
>
>
>
> Email secured by Check Point
>
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
Email secured by Check Point
Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
Posted by Timothy Bish <ta...@gmail.com>.
On 07/01/2014 11:18 AM, Lyubov Romanchuk wrote:
> But what is the purpose of checkForDuplicates? And which functionality will be disabled in case it's false.
>
Surprisingly it checks for duplicates and filter them out in cases where
your client might receive a duplicate message from the broker such as
failover disconnect / reconnect.
> -----Original Message-----
> From: Timothy Bish [mailto:tabish121@gmail.com]
> Sent: Tuesday, July 01, 2014 6:08 PM
> To: dev@activemq.apache.org
> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
>
> On 07/01/2014 10:37 AM, Lyubov Romanchuk wrote:
>> Hi,
>>
>> Thank you for the response.
>> 1) It's very hard to support the test case for reproduction of this
>> issue because I don't know the root cause of the core and we have too
>> complicated environment in order to try to simulate this behaviour
>> 2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
>> 3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
>>
>> Best regards,
>> Lyuba
>>
>> -----Original Message-----
>> From: Timothy Bish [mailto:tabish121@gmail.com]
>> Sent: Tuesday, July 01, 2014 12:20 AM
>> To: dev@activemq.apache.org
>> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
>> activemq::core::ConnectionAudit::isDuplicate
>>
>> On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
>>> Hi,
>>> We use activemqcpp library from the version 3.8.2.
>>> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
>>> Could you please advise with this core - what may cause such crash, is it a known issue?
>>>
>>> Here is the call stack from one of the cores:
>>>
>>> * 1 Thread 32129 0x760417ab in
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>>> n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>> (gdb) bt
>>> #0 0x760417ab in
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>>> n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>>> #1 0x76108cad in
>>> std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestin
>>> ation, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>> std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestinatio
>>> n, decaf::util::concurrent::atomic::AtomicRefCounter> const,
>>> decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> >,
>>> std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::Ac
>>> tiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>
>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> > >,
>>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>>> n, decaf::util::concurrent::atomic::AtomicRefCounter>,
>>> std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::Act
>>> iveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>
>>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>>> decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find
>>> (this=0x874ce14, __k=...) at
>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
>>> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
>>> at
>>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
>>> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate
>>> (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at
>>> decaf/util/StlMap.h:794
>>> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>> (this=0x8a74408, dispatcher=0x32332d46, message=...) at
>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>> #5 0x76141bb5 in
>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>> (this=0xc0a7e88, dispatch=...) at
>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>> (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
>>> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>> (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>> (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
>>> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at
>>> decaf/lang/Thread.cpp:141
>>> #10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8)
>>> at decaf/internal/util/concurrent/Threading.cpp:266
>>> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
>>> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
>>> #13 0x7566024e in clone () from /lib/libc.so.6
>>> (gdb) t 10
>>> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in
>>> dl_iterate_phdr () from /lib/libc.so.6
>>> (gdb) bt
>>> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>>> #1 0x0849cd55 in _Unwind_Find_FDE ()
>>> #2 0x0849a815 in ?? ()
>>> #3 0x0849b0a8 in _Unwind_RaiseException ()
>>> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
>>> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate
>>> (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
>>> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate
>>> (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at
>>> decaf/lang/Pointer.h:258
>>> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>>> (this=0x8a74408, dispatcher=0xb726488, message=...) at
>>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>>> #8 0x76141bb5 in
>>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>>> (this=0x4ff94730, dispatch=...) at
>>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>>> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>>> (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
>>> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>>> (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
>>> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>>> (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
>>> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at
>>> decaf/lang/Thread.cpp:141
>>> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8)
>>> at decaf/internal/util/concurrent/Threading.cpp:266
>>> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod
>>> (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
>>> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
>>> #16 0x7566024e in clone () from /lib/libc.so.6
>>>
>>> Best regards,
>>> Lyuba
>>>
>> No know issue in this area. A test case to reproduce would be helpful.
>>
> You can set connection.checkForDuplicates=false on the URI or call
> factory.setCheckForDuplicates(false) on your ActiveMQConnectionFactory instance to disable duplicate checking which should sort you out.
>
> --
> Tim Bish
> Sr Software Engineer | RedHat Inc.
> tim.bish@redhat.com | www.fusesource.com | www.redhat.com
> skype: tabish121 | twitter: @tabish121
> blog: http://timbish.blogspot.com/
>
>
>
> Email secured by Check Point
>
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
RE: [ActiveMQCPP 3.8.2|Linux] crash in
activemq::core::ConnectionAudit::isDuplicate
Posted by Lyubov Romanchuk <lu...@checkpoint.com>.
But what is the purpose of checkForDuplicates? And which functionality will be disabled in case it's false.
-----Original Message-----
From: Timothy Bish [mailto:tabish121@gmail.com]
Sent: Tuesday, July 01, 2014 6:08 PM
To: dev@activemq.apache.org
Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
On 07/01/2014 10:37 AM, Lyubov Romanchuk wrote:
> Hi,
>
> Thank you for the response.
> 1) It's very hard to support the test case for reproduction of this
> issue because I don't know the root cause of the core and we have too
> complicated environment in order to try to simulate this behaviour
> 2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
> 3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
>
> Best regards,
> Lyuba
>
> -----Original Message-----
> From: Timothy Bish [mailto:tabish121@gmail.com]
> Sent: Tuesday, July 01, 2014 12:20 AM
> To: dev@activemq.apache.org
> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in
> activemq::core::ConnectionAudit::isDuplicate
>
> On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
>> Hi,
>> We use activemqcpp library from the version 3.8.2.
>> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
>> Could you please advise with this core - what may cause such crash, is it a known issue?
>>
>> Here is the call stack from one of the cores:
>>
>> * 1 Thread 32129 0x760417ab in
>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>> n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>> (gdb) bt
>> #0 0x760417ab in
>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>> n, decaf::util::concurrent::atomic::AtomicRefCounter>::operator()
>> (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>> #1 0x76108cad in
>> std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestin
>> ation, decaf::util::concurrent::atomic::AtomicRefCounter>,
>> std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestinatio
>> n, decaf::util::concurrent::atomic::AtomicRefCounter> const,
>> decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>> decaf::util::concurrent::atomic::AtomicRefCounter> >,
>> std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::Ac
>> tiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>
>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>> decaf::util::concurrent::atomic::AtomicRefCounter> > >,
>> decaf::lang::PointerComparator<activemq::commands::ActiveMQDestinatio
>> n, decaf::util::concurrent::atomic::AtomicRefCounter>,
>> std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::Act
>> iveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>
>> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit,
>> decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find
>> (this=0x874ce14, __k=...) at
>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
>> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
>> at
>> /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
>> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate
>> (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at
>> decaf/util/StlMap.h:794
>> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>> (this=0x8a74408, dispatcher=0x32332d46, message=...) at
>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>> #5 0x76141bb5 in
>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>> (this=0xc0a7e88, dispatch=...) at
>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>> (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
>> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>> (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
>> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>> (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
>> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at
>> decaf/lang/Thread.cpp:141
>> #10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8)
>> at decaf/internal/util/concurrent/Threading.cpp:266
>> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod
>> (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
>> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
>> #13 0x7566024e in clone () from /lib/libc.so.6
>> (gdb) t 10
>> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in
>> dl_iterate_phdr () from /lib/libc.so.6
>> (gdb) bt
>> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>> #1 0x0849cd55 in _Unwind_Find_FDE ()
>> #2 0x0849a815 in ?? ()
>> #3 0x0849b0a8 in _Unwind_RaiseException ()
>> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
>> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate
>> (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
>> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate
>> (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at
>> decaf/lang/Pointer.h:258
>> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate
>> (this=0x8a74408, dispatcher=0xb726488, message=...) at
>> decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>> #8 0x76141bb5 in
>> activemq::core::kernels::ActiveMQConsumerKernel::dispatch
>> (this=0x4ff94730, dispatch=...) at
>> activemq/core/kernels/ActiveMQSessionKernel.h:330
>> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch
>> (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
>> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate
>> (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
>> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run
>> (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
>> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at
>> decaf/lang/Thread.cpp:141
>> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8)
>> at decaf/internal/util/concurrent/Threading.cpp:266
>> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod
>> (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
>> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
>> #16 0x7566024e in clone () from /lib/libc.so.6
>>
>> Best regards,
>> Lyuba
>>
> No know issue in this area. A test case to reproduce would be helpful.
>
You can set connection.checkForDuplicates=false on the URI or call
factory.setCheckForDuplicates(false) on your ActiveMQConnectionFactory instance to disable duplicate checking which should sort you out.
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
Email secured by Check Point
Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
Posted by Timothy Bish <ta...@gmail.com>.
On 07/01/2014 10:37 AM, Lyubov Romanchuk wrote:
> Hi,
>
> Thank you for the response.
> 1) It's very hard to support the test case for reproduction of this issue because I don't know the root cause of the core and we have too complicated environment in order to try to simulate this behaviour
> 2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
> 3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
>
> Best regards,
> Lyuba
>
> -----Original Message-----
> From: Timothy Bish [mailto:tabish121@gmail.com]
> Sent: Tuesday, July 01, 2014 12:20 AM
> To: dev@activemq.apache.org
> Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
>
> On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
>> Hi,
>> We use activemqcpp library from the version 3.8.2.
>> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
>> Could you please advise with this core - what may cause such crash, is it a known issue?
>>
>> Here is the call stack from one of the cores:
>>
>> * 1 Thread 32129 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>> (gdb) bt
>> #0 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
>> #1 0x76108cad in std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> >, std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > >, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find (this=0x874ce14, __k=...) at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
>> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
>> at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
>> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at decaf/util/StlMap.h:794
>> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0x32332d46, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>> #5 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0xc0a7e88, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
>> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
>> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
>> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
>> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at decaf/lang/Thread.cpp:141
>> #10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
>> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
>> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
>> #13 0x7566024e in clone () from /lib/libc.so.6
>> (gdb) t 10
>> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>> (gdb) bt
>> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
>> #1 0x0849cd55 in _Unwind_Find_FDE ()
>> #2 0x0849a815 in ?? ()
>> #3 0x0849b0a8 in _Unwind_RaiseException ()
>> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
>> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
>> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at decaf/lang/Pointer.h:258
>> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0xb726488, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
>> #8 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0x4ff94730, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
>> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
>> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
>> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
>> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at decaf/lang/Thread.cpp:141
>> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:266
>> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
>> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
>> #16 0x7566024e in clone () from /lib/libc.so.6
>>
>> Best regards,
>> Lyuba
>>
> No know issue in this area. A test case to reproduce would be helpful.
>
You can set connection.checkForDuplicates=false on the URI or call
factory.setCheckForDuplicates(false) on your ActiveMQConnectionFactory
instance to disable duplicate checking which should sort you out.
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
RE: [ActiveMQCPP 3.8.2|Linux] crash in
activemq::core::ConnectionAudit::isDuplicate
Posted by Lyubov Romanchuk <lu...@checkpoint.com>.
Hi,
Thank you for the response.
1) It's very hard to support the test case for reproduction of this issue because I don't know the root cause of the core and we have too complicated environment in order to try to simulate this behaviour
2) It seems like ConnectionAudit::isDuplicate is not thread safe but may be called from different threads.
3) And I'm not sure that I understand correctly the purposes of isDuplicate. Could you please explain what is it used for and if it's configurable?
Best regards,
Lyuba
-----Original Message-----
From: Timothy Bish [mailto:tabish121@gmail.com]
Sent: Tuesday, July 01, 2014 12:20 AM
To: dev@activemq.apache.org
Subject: Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
> Hi,
> We use activemqcpp library from the version 3.8.2.
> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
> Could you please advise with this core - what may cause such crash, is it a known issue?
>
> Here is the call stack from one of the cores:
>
> * 1 Thread 32129 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
> (gdb) bt
> #0 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
> #1 0x76108cad in std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> >, std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > >, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find (this=0x874ce14, __k=...) at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
> at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at decaf/util/StlMap.h:794
> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0x32332d46, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
> #5 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0xc0a7e88, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at decaf/lang/Thread.cpp:141
> #10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
> #13 0x7566024e in clone () from /lib/libc.so.6
> (gdb) t 10
> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
> (gdb) bt
> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
> #1 0x0849cd55 in _Unwind_Find_FDE ()
> #2 0x0849a815 in ?? ()
> #3 0x0849b0a8 in _Unwind_RaiseException ()
> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at decaf/lang/Pointer.h:258
> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0xb726488, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
> #8 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0x4ff94730, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at decaf/lang/Thread.cpp:141
> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:266
> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
> #16 0x7566024e in clone () from /lib/libc.so.6
>
> Best regards,
> Lyuba
>
No know issue in this area. A test case to reproduce would be helpful.
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/
Email secured by Check Point
Re: [ActiveMQCPP 3.8.2|Linux] crash in activemq::core::ConnectionAudit::isDuplicate
Posted by Timothy Bish <ta...@gmail.com>.
On 06/29/2014 10:16 AM, Lyubov Romanchuk wrote:
> Hi,
> We use activemqcpp library from the version 3.8.2.
> Sometimes there is a crash in activemq::core::ConnectionAudit::isDuplicate.
> Could you please advise with this core - what may cause such crash, is it a known issue?
>
> Here is the call stack from one of the cores:
>
> * 1 Thread 32129 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
> (gdb) bt
> #0 0x760417ab in decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>::operator() (this=0x874ce1c, left=..., right=...) at decaf/lang/Pointer.h:243
> #1 0x76108cad in std::_Rb_tree<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> >, std::_Select1st<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > >, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, std::allocator<std::pair<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> const, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter> > > >::find (this=0x874ce14, __k=...) at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_tree.h:669
> #2 0x76100316 in decaf::util::StlMap<decaf::lang::Pointer<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::Pointer<activemq::core::ActiveMQMessageAudit, decaf::util::concurrent::atomic::AtomicRefCounter>, decaf::lang::PointerComparator<activemq::commands::ActiveMQDestination, decaf::util::concurrent::atomic::AtomicRefCounter> >::containsKey (this=0x874ce10, key=...)
> at /packages/gnu-3.2.3-20.linux30/include/c++/3.2.3/bits/stl_map.h:345
> #3 0x760fb57a in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0xc0a7e94, message=...) at decaf/util/StlMap.h:794
> #4 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0x32332d46, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
> #5 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0xc0a7e88, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
> #6 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0x32332d46, dispatch=...) at decaf/lang/Pointer.h:258
> #7 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0x5a5676a0) at activemq/core/ActiveMQSessionExecutor.cpp:181
> #8 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0x5a6935e0) at activemq/threads/DedicatedTaskRunner.cpp:141
> #9 0x7646285e in decaf::lang::Thread::run (this=0x32332d46) at decaf/lang/Thread.cpp:141
> #10 0x76421c17 in (anonymous namespace)::runCallback (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:266
> #11 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0x5abb66e8) at decaf/internal/util/concurrent/Threading.cpp:254
> #12 0x757f145b in start_thread () from /lib/libpthread.so.0
> #13 0x7566024e in clone () from /lib/libc.so.6
> (gdb) t 10
> [Switching to thread 10 (Thread 32093)]#0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
> (gdb) bt
> #0 0x756951b2 in dl_iterate_phdr () from /lib/libc.so.6
> #1 0x0849cd55 in _Unwind_Find_FDE ()
> #2 0x0849a815 in ?? ()
> #3 0x0849b0a8 in _Unwind_RaiseException ()
> #4 0x75762309 in __cxa_throw () from /usr/lib/libstdc++.so.5
> #5 0x760a6bb8 in activemq::core::ActiveMQMessageAudit::isDuplicate (this=0xbbef390, msgId=...) at decaf/util/HashMap.h:971
> #6 0x760faba1 in activemq::core::ConnectionAudit::isDuplicate (this=0x874cdf4, dispatcher=0x4ff9473c, message=...) at decaf/lang/Pointer.h:258
> #7 0x7603605c in activemq::core::ActiveMQConnection::isDuplicate (this=0x8a74408, dispatcher=0xb726488, message=...) at decaf/util/concurrent/atomic/AtomicRefCounter.h:46
> #8 0x76141bb5 in activemq::core::kernels::ActiveMQConsumerKernel::dispatch (this=0x4ff94730, dispatch=...) at activemq/core/kernels/ActiveMQSessionKernel.h:330
> #9 0x760e4b1b in activemq::core::ActiveMQSessionExecutor::dispatch (this=0xb726488, dispatch=...) at decaf/lang/Pointer.h:258
> #10 0x760e4e92 in activemq::core::ActiveMQSessionExecutor::iterate (this=0xb25f658) at activemq/core/ActiveMQSessionExecutor.cpp:181
> #11 0x762659b6 in activemq::threads::DedicatedTaskRunner::run (this=0xc073290) at activemq/threads/DedicatedTaskRunner.cpp:141
> #12 0x7646285e in decaf::lang::Thread::run (this=0xb726488) at decaf/lang/Thread.cpp:141
> #13 0x76421c17 in (anonymous namespace)::runCallback (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:266
> #14 0x76421b89 in (anonymous namespace)::threadEntryMethod (arg=0xb6ab2c8) at decaf/internal/util/concurrent/Threading.cpp:254
> #15 0x757f145b in start_thread () from /lib/libpthread.so.0
> #16 0x7566024e in clone () from /lib/libc.so.6
>
> Best regards,
> Lyuba
>
No know issue in this area. A test case to reproduce would be helpful.
--
Tim Bish
Sr Software Engineer | RedHat Inc.
tim.bish@redhat.com | www.fusesource.com | www.redhat.com
skype: tabish121 | twitter: @tabish121
blog: http://timbish.blogspot.com/