Javaspaces for Cloud Computing

[Chris Marino]

Gang, what's the word on Javaspaces these days? I don't follow the Java
universe very closely so not sure what's going on with it. I've come
across some papers that talk about using Javaspaces for grid computing,
but they all seem a little dated. Also, I often see Jini mentioned
along with Javaspaces. Not sure why they seem to be coupled, but they
often reference each other's specs.

Javaspaces? Hot, or not?
Jini? Hot, or not?

Anyone here have an opinion on this? Any links would be appreciated as
well.

Thanks in advance.
CM

[Konstantin Ignatyev]

GigaSpaces is very nice implementation and we have mostly positive
experience with it.
I do not know if it is hot, but definitely it is quite capable and
viable platform.

--
Konstantin Ignatyev

PS: If this is a typical day on planet earth, humans will add fifteen
million tons of carbon to the atmosphere, destroy 115 square miles of
tropical rainforest, create seventy-two miles of desert, eliminate
between forty to one hundred species, erode seventy-one million tons
of topsoil, add 2,700 tons of CFCs to the stratosphere, and increase
their population by 263,000

Bowers, C.A. The Culture of Denial: Why the Environmental Movement
Needs a Strategy for Reforming Universities and Public Schools. New
York: State University of New York Press, 1997: (4) (5) (p.206)

[Alan Williamson]

There is the open source alternative to Gigaspaces, if all you want is
basically a JVM that runs as a single 'node' over a wide network

http://www.terracotta.org/

It is significantly easier to setup and manage than Gigaspaces, but they
both have their place to play

--
AW2.0 Ltd - The Cloud Experts
web http://www.aw20.co.uk/
blog http://www.aw20.co.uk/news.cfm

[Ray Voight]

Check into Gigaspaces

Jini has/had great expectations. But I've not tracked its commercialization in some time.

[Konstantin Ignatyev]

Depends on how you are doing that and use case. If you are not
allergic to Maven then setting GS and developing/deploying on GS is
quite convenient.

And for our use cases GS is more transparent and controllable than Terracotta.

However we could get similar results for our use case with using
GridGain + EhCache..., but that will require bunch of custom plumbing
code for monitoring, deployments, etc.

And the solution will be only for the use case, with GS we already
looking into expanding use of other nice GS features, like JMS API.

Anyway, original question was about JINI, and not Terracotta, nor
GridGain implement JINI, while GS is based on JINI.

[Owen Taylor]

The reason Jini and JavaSpaces are mentioned together is that JavaSpaces is a part of the larger Jini definition of valuable distributed services and how they should interact

Check out this website for terrific information on JavaSpaces and Jini: <a href="http://www.dancres.org/blitz/>The Blitz project</a>

JavaSpaces is also alive and well in the form of GigaSpaces which uses a clustered JavaSpaces implementation to provide :
1) access to a large amount of objects stored in memory "what is the state of Account xyz"
2) coordination between services in the form of events  "tell me when Account xyz changes"
3) implementation of transport of service requests and responses in a fault-tolerant and scalable fashion "send this call to an available service and deliver the results to me and be unhindered by failures along the way"

GigaSpaces has done a bunch of other stuff to wrap their JavaSpace in familiar APIs so you can query the space using SQL where clauses and regular expressions, and also use such things as JMS and the Map API
You can also share objects through the space with C++ and .NET services/clients.
 
GigaSpaces is relevant to cloud computing because it allows the application to be decoupled from the physical realities of the runtime environment.  Things like location and number and type of machines are not important to a software service written using GigaSpaces and if they change, the functional behavior of the service will not be changed.  (however, the latency and throughput of the service may change dramatically as the number, location and/or type of machines change)

GigaSpaces uses other aspects of Jini as well as the open source project RIO <a href="https://rio.dev.java.net/overview.html">link</a> to provide rich service management and dynamic discovery so that as new services come online they do so in an automated and proper fashion.

You can read my blog post on the behavior of services deployed into GigaSpaces <a href="http://www.jroller.com/owentaylor/entry/dynamic_service_deployment>here</a>


HTH
Owen.

On Wed, Nov 12, 2008 at 9:15 PM, Chris Marino <christophe...@gmail.com> wrote:

[bytesemantics]

I witnessed a demo of the latest GigaSpaces offering at a GigaSpaces
User Conference back in Septemer this year.

They demonstrated the management of services from a wireless laptop
running the GigaSpaces UI client - connecting to deployed services on
Amazon EC2. They deliberately failed one of the services and forced
migration of the service to another Amazon EC2 instance.

It seemed very straightforward.

Owen is correct in that GigaSpaces uses Rio (both of which are based
on Jini -> now hosted as the Apache Incubator project ->Apache River).

If you want to host a Rio based solution on Amazon EC2 - you could
always follow this:
http://blog.elastic-grid.com/elastic-grid/how-to-start-rio-on-amazon-ec2/


Cheers
Paul