Re: FTP poller stalls...

Fri, 30 Mar 2007 00:23:53 -0800 

No, there are only 5 pollers, so there still is a problem.
I was just being curious as to how these connection pools work...

Guillaume Nodet wrote:

Opps. yes, for sure  ...
But for a single poller, only one call should be made concurrently.
Do you have 23 + 8 pollers ?
And in this case, each poller has its own FTP connection pool,
so there's no reason why they would all be blocked ...


On 3/30/07, Gert Vanthienen <[EMAIL PROTECTED]> wrote:


Guillaume,

Isn't the poll method called concurrently when multiple <ftp:poller/>s
exist?

Gert

Guillaume Nodet wrote:
> Hi Guert !
>
> Yeah, I guess the accept operation on the socket should timeout somehow, 
> but this would be an enhancement in commons-net (maybe they know what
> to do for handling such problems ...).
> Another way would be to improve the pooling strategy with timeouts,
> aso ...
>
> But what seems weird is that there are 8 threads blocked in the poll
> method,
> which should not be called concurrently.  So there is at least a bug
> there
> -- please raise a JIRA for this one :-)
>
> On 3/30/07, Gert Vanthienen <[EMAIL PROTECTED]> wrote:
>>
>> L.S.,
>>
>>
>> After some time of well-behaved operations, the FTP poller stalls...
>> Below, you find a set of thread dumps.  If I interpret this data
>> correctly, the poller threads are waiting on a network operation to
>> complete, causing the connection pool to become empty --threads waiting >> on GenericObjectPool.borrowObject()--. How do I avoid this? Is there 
a
>> way to set a time-out somewhere?  Or is this a bug and should I raise
an
>> issue for this --and attach a patch afterwards ;) -- ?
>>
>>
>> Regards,
>>
>> Gert
>>
>>
>>
>> 1 thread performing timed wait (which is good)
>> -----------------------------------------------
>> Name: pool-component.servicemix-ftp-thread-1
>> State: TIMED_WAITING on
>> [EMAIL PROTECTED]
>> Total blocked: 0  Total waited: 429.516
>>
>> Stack trace:
>>     java.lang.Object.wait(Native Method)
>>     java.lang.Object.wait(Object.java:432)
>>
>> edu.emory.mathcs.backport.java.util.concurrent.TimeUnit.timedWait(
>> TimeUnit.java:301)
>>
>> edu.emory.mathcs.backport.java.util.concurrent.locks.CondVar.await(
>> CondVar.java:103)
>>
>> edu.emory.mathcs.backport.java.util.concurrent.ArrayBlockingQueue.poll( 
>> ArrayBlockingQueue.java:345)
>>
>> org.apache.servicemix.jbi.messaging.DeliveryChannelImpl.accept(
>> DeliveryChannelImpl.java:252)
>>
>> org.apache.servicemix.common.AsyncBaseLifeCycle.pollDeliveryChannel(
>> AsyncBaseLifeCycle.java:266)
>>
>> org.apache.servicemix.common.AsyncBaseLifeCycle$1.run(
>> AsyncBaseLifeCycle.java:252)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.runTask 
>>
>> (ThreadPoolExecutor.java:665)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.run 
>>
>> (ThreadPoolExecutor.java:690)
>>     java.lang.Thread.run(Thread.java:595)
>>
>> 8 threads that are waiting on some kind of network operation
>> -------------------------------------------------------------
>> Name: pool-component.servicemix-ftp-thread-9
>> State: RUNNABLE
>> Total blocked: 742.403  Total waited: 35.249
>>
>> Stack trace:
>>     java.net.PlainSocketImpl.socketAccept(Native Method)
>>     java.net.PlainSocketImpl.accept(PlainSocketImpl.java:384)
>>     java.net.ServerSocket.implAccept(ServerSocket.java:450)
>>     java.net.ServerSocket.accept(ServerSocket.java:421)
>>
>> org.apache.commons.net.ftp.FTPClient._openDataConnection_(
FTPClient.java
>> :502)
>>
>> org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java 
>> :2390)
>>
>> org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java 
>> :2364)
>> org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2141) 
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.pollFileOrDirectory(
>> FtpPollerEndpoint.java:211)
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.pollFileOrDirectory(
>> FtpPollerEndpoint.java:203)
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.poll(FtpPollerEndpoint.java 
>> :78)
>>
>>
>>
org.apache.servicemix.common.endpoints.PollingEndpoint$PollSchedulerTask$1.run 
>>
>> (PollingEndpoint.java:155)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.runTask 
>>
>> (ThreadPoolExecutor.java:665)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.run 
>>
>> (ThreadPoolExecutor.java:690)
>>     java.lang.Thread.run(Thread.java:595)
>>
>> 23 threads that are waiting to get a connection from the pool
>> -------------------------------------------------------------
>> Name: pool-component.servicemix-ftp-thread-32
>> State: WAITING on [EMAIL PROTECTED] 
>> Total blocked: 301  Total waited: 17
>>
>> Stack trace:
>>     java.lang.Object.wait(Native Method)
>>     java.lang.Object.wait(Object.java:474)
>>
>> org.apache.commons.pool.impl.GenericObjectPool.borrowObject(
>> GenericObjectPool.java:748)
>>
>> org.apache.servicemix.ftp.SocketClientPoolSupport.borrowClient(
>> SocketClientPoolSupport.java:61)
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.borrowClient(
>> FtpPollerEndpoint.java:323)
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.pollFileOrDirectory(
>> FtpPollerEndpoint.java:200)
>>
>> org.apache.servicemix.ftp.FtpPollerEndpoint.poll(FtpPollerEndpoint.java 
>> :78)
>>
>>
>>
org.apache.servicemix.common.endpoints.PollingEndpoint$PollSchedulerTask$1.run 
>>
>> (PollingEndpoint.java:155)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.runTask 
>>
>> (ThreadPoolExecutor.java:665)
>>
>>
>>
edu.emory.mathcs.backport.java.util.concurrent.ThreadPoolExecutor$Worker.run 
>>
>> (ThreadPoolExecutor.java:690)
>>     java.lang.Thread.run(Thread.java:595)
>>
>>
>>
>
>

Reply via email to