BT

Grid Computing Overview

| by Stefan Tilkov Follow 5 Followers on May 25, 2006. Estimated reading time: less than one minute |
Tim Bray, co-inventor of XML and high profile blogger, has posted a useful overview of alternatives for Grid Computing, including:
Tim does not have kind words for WSRF:
Not only is my antipathy to the WS-* suite well-known, but the specs clustering around WSRF have always struck me as particularly offensive, since on the face of it they seem to re-implement HTTP (badly) on top of SOAP on top of HTTP.

Rate this Article

Adoption Stage
Style

Hello stranger!

You need to Register an InfoQ account or or login to post comments. But there's so much more behind being registered.

Get the most out of the InfoQ experience.

Tell us what you think

Allowed html: a,b,br,blockquote,i,li,pre,u,ul,p

Email me replies to any of my messages in this thread

Tangosol Coherence InvocableMap and Grid Features by Jason Carreira

He briefly mentions Tangosol, but he should have checked out their grid processing support:

wiki.tangosol.com/display/COH31UG/Scaling Out Your Data Grid Aggregations Linearly

Re: Tangosol Coherence InvocableMap and Grid Features by Cameron Purdy

Spaces in URLs .. ;-)

tinyurl.com/zobej

follow up by Cameron Purdy

(as posted originally on TSS)

Building "sigrid" may have been a fun exercise for Tim, but business application architects and developers are looking for some pretty specific things, such as:

1) stable state image, even during and after server failure
2) resiliency and consistency of operations across a distributed environment
3) guaranteed semantics, such as "once and only once" and "guaranteed delivery"
4) all or nothing semantics (e.g. no "partial failures")
5) automatonic processing (e.g. no manual recovery of transaction logs, no manual rollforwards and rollbacks)

Only after guaranteeing the various necessary qualities of service can one even earn the right to worry about scalability. One cannot later add correctness and deterministic behavior to a system. It is either designed in, or it is not.

Regarding the capabilities that were described in the article, the map/reduce capability and much more (but with the guarantees stated above) has been available in our Coherence product for a while now (Jason posted a link), as has the grid-wide batch and service invocation capabilities (since 2003). The truth is that Tim wanted to do something fun, so he made sure that there was nothing out there that would prevent him from deciding to have some fun ;-)

Here's the problem, though:

My problem is that I?ve been a Unix guy for twenty years and a Web guy for ten. My feeling is that if something says it?s a service, the right way to talk to it is to get a hostname/port-number combination, call it up, send a request, and wait for a response.


Tim is still thinking in 1980s terms. He is still thinking client/server, but he's trying to rename it as a grid.

Servers no longer have a hostname/port. In the grid, there is no such thing as a server. All you have is the grid. The servers within the grid are no more individually addressable and reachable than the CPUs within a particular server. If the grid needs to expose a service, it does so through a port on a load balancer that represents the grid as a whole.

Apologies to Sun, but:

The Grid is the Computer.

Peace,

Cameron Purdy
Tangosol Coherence: The Java Data Grid

Allowed html: a,b,br,blockquote,i,li,pre,u,ul,p

Email me replies to any of my messages in this thread

Allowed html: a,b,br,blockquote,i,li,pre,u,ul,p

Email me replies to any of my messages in this thread

3 Discuss
BT