To quote Servlet spec SRV.7.7.3 "Within an application marked as distributable, all requests that are part of a session must be handled by one JVM at a time." I read that as "Concurrent requests must be dispatched to the same JVM - otherwise all bets are off."
So any upstream load balancing in a cluster must use some sort of session affinity, and in the same JVM the internalized session id is guaranteed to be unique. Cheers, Alfred. -----Original Message----- From: Joerg Heinicke [mailto:[EMAIL PROTECTED] Sent: Montag, 23. Mai 2005 20:45 To: dev@cocoon.apache.org Subject: Re: Synchronization on session object (was svn commit: r169856 - /cocoon/branches/BRANCH_2_1_X/src/java/org/apache/cocoon/environment/htt p/HttpRequest.java) On 13.05.2005 11:37, Nathaniel Alfred wrote: > I think synchronized(session) should never be used as vehicle to > coordinate concurrent requests because there is no convincing guarantee > that it is always working as expected. > > Joerg, if you want to do it in your usercode, I don't mind, but please > don't use it in common Cocoon code. My propesed alternative of > synchronized(session.getId().intern()) may look obscure but at least > it is guaranteed to work. I think we don't get a final answer to whether synchronized(session) is supposed to work or not. Your main concern seems to be complex environments like clusters. But how is session.getId().intern() supposed to work? Have the cluster nodes running by different JVMs and it does neither work. Or am I wrong? Joerg This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. No confidentiality or privilege is waived or lost by any mistransmission. If you receive this message in error, please notify the sender urgently and then immediately delete the message and any copies of it from your system. Please also immediately destroy any hardcopies of the message. You must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message if you are not the intended recipient. The sender's company reserves the right to monitor all e-mail communications through their networks. Any views expressed in this message are those of the individual sender, except where the message states otherwise and the sender is authorised to state them to be the views of the sender's company.
