Jrebel version update#
With a careful design this lazy approach neither sacrifices the update flexibility nor introduces unnecessary object validity checks or access indirections.Įvaluation experiments show that Javelus can reduce the updating pausing time by one to two orders of magnitude without introducing observable overheads before and after the dynamic updating. Instead of updating everything at once when the running application is suspended, Javelus only updates the changed code during the suspension, and migrates stale objects on-demand after the application is resumed. In this paper we present Javelus, a Java HotSpot VM-based Java DSU system with very short pausing time. State-of-the-art Java DSU systems are unsatisfactory as they may cause a non-negligible system pause during updating.
Jrebel version software#
Dynamic software updating (DSU) migrates a running software system to a new version without stopping it. Shutting down a running system before updating it is a normal practice, but the service unavailability can be annoying and sometimes unacceptable. In-use software systems are destined to change in order to fix bugs or add new features. Our Runtime Code Updates scheme has been integrated into the Smalltalk/X IDE, thus providing interactive environment where a developer can modify a Java application while it is running. Beside changes to the fields and methods which are already supported by the tools such as JRebel or Javaleon, we also support unrestricted changes to the class and interface hierarchy. We have modified STX:LIBJAVA – an implementation of Java virtual machine within Smalltalk/X – to support arbitrary changes to the running code. Current virtual machines for Java programming language do not support non-trivial updates to the running code. Furthermore, there are applications which cannot be stopped, such as air traffic control systems or telephone switches. Such a feature is often used so the developer can modify an application without the necessity to restart the application and recover desired state after restart. Runtime Code Update is a technique to update a program while it is running.