cluster-computing

问题 I have a question regarding speed & performance of using multiple virtualized nodes in a single machine VS single node on the single machine itself. which one will perform better? The reason why I ask this question is because I am currently learning hadoop on a single machine, and I see some tutorials on the internet that shows the use of multiple virtualized nodes in a single machine. Thank you in advance 回答1: There is always some overhead that comes with virtualization, so unless really

问题 Is there a way to programmatically determine which node in a SQL Server failover cluster is the active node ? Or at least determine whether the current machine is the active node? I have a Windows program which runs on both physical nodes in a failover cluster, but that should operate differently depending on whether it is running on the active node. Part of the reason is that this program should not run simultaneously on the inactive and the active node . (I've read a bit about making the

问题 I've a four-node Hadoop cluster on Softlayer. The master (NameNode) has a public IP address for external access and a private IP address for cluster access. The slave nodes (datanodes) have private IP address which I'm trying to connect to the master without the need of assigning public IP addresses to each slave node. I've realised that setting fs.defaultFS to the NameNode's public address allows for external access, except that the NameNode only listens to that address for incoming

问题 I've successfully setup a cluster of 2 JBoss AS 7 instances, and deployed the following SLSB: @Stateless @Remote(TestEJBRemote.class) @Clustered public class TestEJB implements TestEJBRemote { private static final long serialVersionUID = 1L; private static final Logger logger = Logger.getLogger(...); @Override public void test() { String nodeName = System.getProperty("jboss.node.name"); logger.info(nodeName); } } From the log files I can see that the bean is correctly deployed on the cluster.

问题 I have a Glassfish 3.1.2 that runs in a cluster and a EJB 3.1 application. And I need two kind of Scheduled Methods in my application: one kind that runs only once (on a single node) once a day and other kind that runs on all nodes (every 1-2 Minutes) -- They do NOT need to run a syncron way! The requirement is just that this kind run on every node. I have no clue how to start with this cluster - problem, is this possible with @Schedule (and how) or do I need something else? 回答1: I faced the

问题 I having a problem with clustering my application with Node.js, socket.io and node.js clusters. I using the socket.io-redis to share the information for all workers, but is not working. My code: var cluster = require('cluster'); var numCPUs = require('os').cpus().length; if (cluster.isMaster) { // Fork workers. for (var i = 0; i < numCPUs; i++) { cluster.fork(); } cluster.on('exit', function(worker, code, signal) { console.log('worker ' + worker.process.pid + ' died'); }); } else { ... var

问题 What is the difference between a Cluster and MPP supercomputer architecture? 回答1: In a cluster, each machine is largely independent of the others in terms of memory, disk, etc. They are interconnected using some variation on normal networking. The cluster exists mostly in the mind of the programmer and how s/he chooses to distribute the work. In a Massively Parallel Processor, there really is only one machine with thousands of CPUs tightly interconnected. MPPs have exotic memory architectures

问题 I’ve successfully used snowfall to setup a cluster on a single server with 16 processors. require(snowfall) if (sfIsRunning() == TRUE) sfStop() number.of.cpus <- 15 sfInit(parallel = TRUE, cpus = number.of.cpus) stopifnot( sfCpus() == number.of.cpus ) stopifnot( sfParallel() == TRUE ) # Print the hostname for each cluster member sayhello <- function() { info <- Sys.info()[c("nodename", "machine")] paste("Hello from", info[1], "with CPU type", info[2]) } names <- sfClusterCall(sayhello) print

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 3 years ago . 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) 回答1: I've looked

问题 Here in the DCOS documents it is stated that "Deciding where to run processes to best utilize cluster resources is hard, NP-hard in-fact." I don't deny that that sounds right, but is there a proof somewhere? 回答1: Best utilization of resources is variation of bin packaging problem: In the bin packing problem, objects of different volumes must be packed into a finite number of bins or containers each of volume V in a way that minimizes the number of bins used. In computational complexity theory