cluster-computing

I've got some code that looks very much like the sample in the Cluster documentation at http://nodejs.org/docs/v0.6.0/api/cluster.html , to wit: var cluster = require('cluster'); var server = require('./mycustomserver'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { var i; // Master process for (i = 0; i < numCPUs; i++) { cluster.fork(); } cluster.on('death', function (worker) { console.log('Worker ' + worker.pid + ' died'); }); } else { // Worker process server.createServer({port: 80}, function(err, result) { if (err) { throw err; } else { console.log('Thread listening on

I am searching for a java framework that would allow me to share a cache between multiple JVMs. What I would need is something like Hazelcast but without the "distributed" part. I want to be able to add an item in the cache and have it automatically synced to the other "group member" cache. If possible, I'd like the cache to be sync'd via a reliable multicast (or something similar). I've looked at Shoal but sadly the "Distributed State Cache" seems like an insufficient implementation for my needs. I've looked at JBoss Cache but it seems a little overkill for what I need to do. I've looked at

I'm planning on making a distributed database system using a shared-nothing architecture and multiversion concurrency control . Redundancy will be achieved through asynchronous replication (it's allowed to lose some recent changes in case of a failure, as long as the data in the system remains consistent). For each database entry, one node has the master copy (only that node has write access to it), in addition to which one or more nodes have secondary copies of the entry for scalability and redundancy purposes (the secondary copies are read-only). When the master copy of an entry is updated,

This is a rather simple question but I haven't been able to find an answer. I have a large number of jobs running in a cluster (>20) and I'd like to delete them all and start over. According to this site I should be able to just do: qdel -u netid to get rid of them all, but in my case that returns: qdel: invalid option -- 'u' usage: qdel [{ -a | -c | -p | -t | -W delay | -m message}] [<JOBID>[<JOBID>]|'all'|'ALL']... -a -c, -m, -p, -t, and -W are mutually exclusive which obviously indicates that the command does not work. Just to check, I did: qstat -u <username> and I do get a list of all my

What is the difference between Clustering and Load balancing ? I know it is a simple question.But I asked this question to several people, But no one gave reliable answer. Also I googled a lot and can't get an exact answer . Hope our Stack users will give the best answer for me. From Software journal blog an extract. Clustering has a formal meaning. A cluster is a group of resources that are trying to achieve a common objective, and are aware of one another. Clustering usually involves setting up the resources (servers usually) to exchange details on a particular channel (port) and keep

ZooKeeper is a highly available coordination service for data centers. It originated in the Hadoop project. One can implement locking, fail over, leader election, group membership and other coordination issues on top of it. Are there any alternatives to ZooKeeper? (free software of course) I've looked extensively at Zookeeper/ Curator , Eureka , etcd , and consul. Zookeeper/Curator and Eureka are in many ways the most polished and easiest to integrate if you are in the Java world. Etcd is pretty cool and very flexible, but It is really just a HA key store so you would have to write a lot of

(update 11/09/2017 question) this is my codes to cluster kmodes in R: library(klaR) setwd("D:/kmodes") data.to.cluster <- read.csv('kmodes.csv', header = TRUE, sep = ';') cluster.results <- kmodes(data.to.cluster[,2:5], 3, iter.max = 10, weighted = FALSE) plot(data.to.cluster[,2:5],col= cluster.results$cluster) the result is like this image : http://imgur.com/a/Y46yJ My sample data : https://drive.google.com/file/d/0B-Z58iD3By5wUzduOXUwUDh1OVU/view Is there a way to show total number in same coordinate? I mean when clustering if there are many value which is same as 1,1 (x,y) could we make r