Re: NioEndpoint closes connection upon timeout
Reich, Matthias wrote: -Original Message- From: Filip Hanik - Dev Lists [mailto:[EMAIL PROTECTED] Sent: Tuesday, May 08, 2007 11:00 AM However, the Javadoc of enum EventSubType says: TIMEOUT - the connection timed out (sub type of ERROR); note that this ERROR type is not fatal, and the connection will not be closed unless the servlet uses the close method of the event. hmm, not sure I agree with the docs. let me check on that. in the meantime, why don't you set a much higher timeout value for the NIO connector you can do this on a per-connection basis. just do event.setTimeout during the BEGIN event. Filip My servlet does not close the event in case of a TIMEOUT, you're servlet SHOULD ALWAYS call event.close upon any type of error. Well, there is still no common understanding about what a TIMEOUT really means within the code base and the documentation. E.g. the Javadoc for CometEvent says: ERROR - Error will be called by the container in the case where an IO exception or a similar unrecoverable error occurs on the connection. Fields that have been initialized in the begin method should be reset. After this event has been processed, the request and response objects, as well as all their dependent objects will be recycled and used to process other requests. However, the CoyoteAdapter does *not* treat a timeout as an error and does *not* recycle any objects, and this behavior works fine with Apr connector - i.e. the Servlet can decide if this is an error situation and close the event if appropriate. No matter what the final meaning of a timeout will be - the behavior should be the same for both connectors, i.e. either both connectors should close the connection upon a timeout, or both should keep it open. yes, I agree, I made the modification to the NIO connector to handle it the same way as APR. basically, the connection stays open, and if Keep Alive is turned on, you can reuse it for another HTTP request. This means that it is now the developers responsibility to notify the client that the connection is no longer a "comet" connection. My personal preference is that TIMEOUT is an error and should close the connection, but for the sake of consistency, both connectors should now behave in the same manner. Filip Matthias - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: NioEndpoint closes connection upon timeout
> -Original Message- > From: Filip Hanik - Dev Lists [mailto:[EMAIL PROTECTED] > Sent: Tuesday, May 08, 2007 11:00 AM > > > > However, the Javadoc of enum EventSubType says: > > > > TIMEOUT - the connection timed out (sub type of ERROR); > note that this > > ERROR type is not fatal, and the connection will not be > closed unless > > the servlet uses the close method of the event. > > > hmm, not sure I agree with the docs. let me check on that. > in the meantime, why don't you set a much higher timeout value > for the NIO connector you can do this on a per-connection basis. > just do event.setTimeout during the BEGIN event. > > Filip > > My servlet does not close the event in case of a TIMEOUT, > > > you're servlet SHOULD ALWAYS call event.close upon any type of error. Well, there is still no common understanding about what a TIMEOUT really means within the code base and the documentation. E.g. the Javadoc for CometEvent says: ERROR - Error will be called by the container in the case where an IO exception or a similar unrecoverable error occurs on the connection. Fields that have been initialized in the begin method should be reset. After this event has been processed, the request and response objects, as well as all their dependent objects will be recycled and used to process other requests. However, the CoyoteAdapter does *not* treat a timeout as an error and does *not* recycle any objects, and this behavior works fine with Apr connector - i.e. the Servlet can decide if this is an error situation and close the event if appropriate. No matter what the final meaning of a timeout will be - the behavior should be the same for both connectors, i.e. either both connectors should close the connection upon a timeout, or both should keep it open. Matthias - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: NioEndpoint closes connection upon timeout
Reich, Matthias wrote: The NioEndpoint seems to close a connection during the timeout handling. My client reacts to a connection failure with a resubmit of the last request, and I see this in the log: 07.05.2007 22:08:14 comettest.CometServlet event WARNUNG: BEGIN(16) POST /comettest/comet/request?action=poll&count=1 07.05.2007 22:08:35 comettest.CometServlet event WARNUNG: ERROR/TIMEOUT(16) POST /comettest/comet/request?action=poll&count=1 07.05.2007 22:08:35 comettest.CometServlet event WARNUNG: BEGIN(17) POST /comettest/comet/request?action=poll&count=1 I had a look into the code and found that NioEndpoint.timeout calls cancelledKey(key, SocketStatus.TIMEOUT,true); Method cancelledKey processes the timeout event and then closes the channel. However, the Javadoc of enum EventSubType says: TIMEOUT - the connection timed out (sub type of ERROR); note that this ERROR type is not fatal, and the connection will not be closed unless the servlet uses the close method of the event. hmm, not sure I agree with the docs. let me check on that. in the meantime, why don't you set a much higher timeout value for the NIO connector you can do this on a per-connection basis. just do event.setTimeout during the BEGIN event. Filip My servlet does not close the event in case of a TIMEOUT, and thus the CoyoteAdapter won't recycle the processor. The consequence is that Tomcat runs out of memory after a while if my asynchronous response provider thread often waits longer than the connection timeout before sending an answer. you're servlet SHOULD ALWAYS call event.close upon any type of error. According to a note which was still present in the Tomcat 5.5 server.xml file, I tried to set the connectionTimeout value to 0 to disable connection timeouts, but that does no longer seem to work with Tomcat 6, at least not with the Nio connector. see the note about per-connection timeout, also, you can set socket.soTimeout see the documentation Thus, I think this behavior of the NioEndpoint must be considered a bug. (Also, the Apr connector does not close the connection upon a TIMEOUT event.) If it should not be possible to provide a short term solution which keeps the connection open, perhaps the behavior of NioEndpoint.timeout can be modified to signal a DISCONNECT instead of a TIMEOUT, even if it was the server and not the client that disconnected. This would allow the Servlet and the CoyoteAdapter to clean up more properly. Matthias - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
