On Tue, Apr 19, 2011 at 4:51 AM, David Schlosnagle <[email protected]> wrote: > I'd be interested to see what you find. Here are a few links [1] [2] [3] > from a few years back when I did a little investigation of isolating > multiple apps in a single JVM. For my needs I ended up with separate JVMs to > satisfy some other constraints (e.g. some components were focused on low > latency responses, while others were focused on pure throughput, so it made > sense to separate these and apply different GC policies). > [1] Secure and Reliable Java-Based Middleware - Challenges and > Solutions http://www.inf.usi.ch/faculty/binder/documents/ares06.pdf > [2] JSR 121: Application Isolation API > Specification http://jcp.org/en/jsr/detail?id=121 > [3] JSR 284: Resource Consumption Management > API http://jcp.org/en/jsr/detail?id=284
I was on the experts groups for both of these, and I built the reference implementation for JSR 121. The RI was a multi-process model built on the then-current JDK (this was 1.4 era IIRC, some time in 2002). JSR 284 was intended as a follow-on from 121 adding resource control as a layer on top of the latter's isolation and management mechanisms. I'm sorry to say that both JSRs are long since dead. At the time the main issues which seemed to be exercising Sun were memory footprint and startup time. A multi-process JVM didn't do anything to address those, quite the opposite in fact. And the Multitasking Virtual Machine (a Sun Labs project led by Grzegorz Czajkowski, now at Google) never had enough resources put behind it to make it into production. In fact that was the main theme of the process ... Sun were insufficiently committed to the project to put the resources into it to make it a success as part of a mainstream JVM, and nor were any of the other participants. I did the RI work as an EG member (I've never been a Sun employee) because we needed a concrete implementation to play with to validate the design of the API. This was very much pre-open-source Java times, however, and to get access to the JDK/JVM sources I had no option but to sign a IP assignment agreement which handed all the IP to Sun. Much to everybody's frustration, Sun refused to allow the resulting modified JVM to be distributed even to the other EG members. I didn't feel particularly motivated to contribute to any other JSRs after that ... Cheers, Miles -- Miles Sabin tel: +44 7813 944 528 gtalk: [email protected] skype: milessabin http://www.chuusai.com/ http://twitter.com/milessabin -- You received this message because you are subscribed to the Google Groups "JVM Languages" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jvm-languages?hl=en.
