[ https://issues.jboss.org/browse/WFCORE-3948?page=com.atlassian.jira.plugi... ] Scott Marlow commented on WFCORE-3948: -------------------------------------- Assuming that ManifestClassPathProcessor, ManifestDependencyProcessor and DeploymentStructureDescriptorParser are running during the STRUCTURE phase, because they have to. If we introduced a STRUCTURE2 phase, we could expect ADDITIONAL_MODULES writing is done during the (first) STRUCTURE phase and by the time we reach the second STRUCTURE2 phase, it is safe to read the ADDITIONAL_MODULES. At least this could be a goal, that we could see if we could reach. Another high level idea, since the ManifestClassPathProcessor.deploy() is already synchronized, if ManifestDependencyProcessor.deploy() and DeploymentStructureDescriptorParser.deploy() were made to also synchronize on the same object, we would slow deployment time but I think wouldn't see the ConcurrentModificationException any more. Or slightly better performing idea, could be to use a ReadWriteLock, where ManifestClassPathProcessor, ManifestDependencyProcessor and DeploymentStructureDescriptorParser code that reads ADDITIONAL_MODULES, waits on a shared read lock and writes to ADDITIONAL_MODULES waits on an exclusive write lock. -- This message was sent by Atlassian Jira (v7.13.8#713008)