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Questions tagged [cluster]

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0
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1answer
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Processing data in a cluster with multiple tasks

The goal is to provide a scaleable system implementing multiple data processing tasks which can be seen as a graph. Data objects will travel that graph. Most object will visit the same nodes in the ...
0
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1answer
88 views

Clustering Algorithm with max number of clusters

I'm looking for a clustering algorithm (ideally density based) that allows me to specify the maximum number of clusters (but not the exact number). All points must be assigned to a cluster, so I can't ...
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0answers
543 views

what's the maximum number of simultaneous java socket connections in the cluster?

we work within a cluster of 1 gb/s of bandwidth, we use java sockets to perform some data transfer between the cluster's nodes like broadcast and shuffle (nodes of the cluster exchange data) in the ...
2
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1answer
79 views

Validation layer of clustered WebApi solution

Currently I have a design problem, which I am not sure how exactly to solve and what would be the best approach. So what I have is a ASP.NET Core WebApi project which is actually clustered solution. ...
1
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1answer
49 views

should I use server cluster when my application does not work with session

I read about payara(glassfish) server cluster and find out that clustering with payara only replicate session in multiple servers. but I use jwt for my project so I don't use session at all. I ...
5
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1answer
267 views

Nodejs cluster: are there any downsides?

I was reading a litte about clusters in nodejs, and in all cases it was trivial to clusterize the application. In fact, it was so easy that I began to wonder: are there any cases that I shoudn't use ...
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0answers
273 views

Using a hardware load balancer for PostgreSQL / MySQL

I need to ensure high availability of my 3-tier architecture system. Currently I have the database mirrored by using MySQL Master-Master. All app boxes talk to the primary DB server In case of ...
3
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1answer
272 views

Clustering of points that minimizes overall average distance to given center

Given a situation like this: where the position of the triangles is given (it does not need to be calculated by an algorithm). I would like to find clusters of circles around the triangles. Each ...
1
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0answers
440 views

efficient graph clustering algorithm for weighted directed graphs based on node and edge weights

I'm looking for an algorithm to cluster weighted directed graphs that have weights on both edges and vertices. I'm using graphs with multiple weights(labels) on vertices and a weight on edges that ...
5
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2answers
552 views

Master-Slave Cluster - How to make sure the master is really dead for the slave to take over?

I have a in-house messaging system, similar to a message broker. We have one master message broker and one slave message broker. A message broker just receives messages and sends them to all nodes. ...
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0answers
77 views

Should mongoDB be run in a cluster?

I'm trying to implement an architecture that's similar to the coreos's production architecture (shown below) Should I run the database as a central service or one or more of the workers? I figured ...
3
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4answers
1k views

Failover for High Frequency Jobs

I have a job that runs at a fairly high frequency (~1x every second). This job needs to be executed constantly as long as the web app is running. However, I really only want 1 instance of the job ...
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0answers
95 views

algorithm for group reassignment of points

I have a list of clustered points but they are not in the cluster which has the center closest to them. The objective is to reassign them to minimize the total distance of each point to its cluster ...
0
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1answer
68 views

Using Euclidan Distance to intialize centroid of K-Means

I need to initialize centroid of K-Means using Euclidan distance. Is it possible? If so how the algorithm should be? I have been stuck for a while and couldn't figure it out. Thanks for your time.
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0answers
293 views

handling external events in a cluster environment

I have an app written with JSF and Spring using JPA+Hibernate which is running on a Glassfish4 server. Right now I have an Observer pattern which is listening for some Postgresql events. Let`s say ...
1
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1answer
674 views

Image segmentation - show or hide clusters

I'm trying to make a small program in c#, that will downsample image to specified amount of colors (using K-means). Then, user will be able to hide\show colored areas(clusters) in image. I've ...
3
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3answers
2k views

Design a Queuing Solution with Clustering and Multiple Consumers

It is a Design Problem which I am listing out here. I have different set of business operations that are carried out for different business entities. Operations: Operation A Operation B Operation ...
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2answers
1k views

Java Web Application in Cluster with Shared Database. How to Negotiate an Instance to do Updates? How to Notify Instances of Updates? [duplicate]

I have a Java web application, running in a cluster of Tomcat application servers and a shared SQL/JDBC database. Data from the database is cached in memory in each instance of the web app. My web ...
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2answers
314 views

How to minimize networking cost of distributed game database?

We've been working on a networked online game project which will run in near future and looking for a satisfying solution for our distributed game database. We didn't take networking costs into ...
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0answers
139 views

Session Management in distributable web-apps

I am working on a huge web application in which I need to add transparent failover feature. I understand the necessary steps to make a web application distributable, the most difficult thing being: to ...
0
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0answers
626 views

Embedded Tomcat Cluster

Can someone please explain with an example how an Embedded Tomcat Cluster works. Would a load balancer be necessary? Since we're using embedded tomcat, how would two separate jar files (each a ...
6
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2answers
2k views

How does Elastic Search approach the problem of distributed membership and consensus?

I already understand that Elastic Search is supposed to be deployed in a distributed topology, in that you can have multiple nodes for a cluster of ES instances. I like the API, and it looks ...
2
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1answer
415 views

Random forest ML algorithm suitable for use on cluster based HPC?

I need help in identifying a better algorithm. I have developed a script using pythons scipy package to analyse a rather large model that I wish to solve. The model contains over 12GB of data ...
2
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1answer
3k views

Session serialization in JavaEE environment

Please consider the following scenario: We are working on a JavaEE project for which the scalability starts to become an issue. Up until now, we were able to scale up but this is no longer an option. ...
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2answers
680 views

Determine Cluster Label in K-means

I have dataset that is contain 150 data that is actually divided into 3 group. Each group has it’s own label. I do clustering process with K-means algorithm to group the data. I need to assign the ...
1
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1answer
1k views

Why does storm not supply a mechanism for supplying topology necessary dependent jars other than the fat jar?

Following is a question that I had posted at the incubator-storm-user mailing list (verbatim). I had decided to open up the question here as well, because it also contains a conceptual side to it, ...
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2answers
987 views

Improving ZooKeeper to increase availability

Running Apache ZooKeeper (this applies to PAXOS style system just as well) with 2 members - which is not recommended - does not make sense, because if either member1 goes down member2 goes down ...
1
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1answer
424 views

How to test issues in a local development environment that can only be introduced by clustering in production?

We recently clustered an application, and it came to light that because of how we're doing SSL offloading via the load balancer in production it didn't work right. I had to mimic this functionality on ...
19
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5answers
638 views

Algorithm to Find the Aggregate Mass of “Granola Bar”-Like Structures?

I'm a planetary science researcher and one project I'm working on is N-body simulations of Saturn's rings. The goal of this particular study is to watch as particles clump together under their own ...
3
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0answers
371 views

How to deal with runtime changes to tenant-location in a clustered, multitenant web application with app-managed datasources?

I have a Java web application that supports multi-tenancy to keep customer data separate. Connection pools to each customer database are created at runtime. The details of each customer shard (...
0
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1answer
133 views

which is better of these two architectures and why

PhpServer will handle gSoap requests and http requests from clients. PushServer will push notifications to clients and act a file server. There are many server machines. Every PhpServer will ...
6
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2answers
2k views

Clustering Strings on the basis of Common Substrings

I have around 10000+ strings and have to identify and group all the strings which looks similar(I base the similarity on the number of common words between any two give strings). The more number of ...
6
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1answer
54k views

What is the difference between a server and a mainframe? [closed]

To me, it seems as though "mainframe" is a somewhat dated term; is it simply an older synonym of "server," or does it server a purpose more similar to a cluster/supercomputer?
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2answers
435 views

Relation of CPU Hz's and network speed in clusters

In cluster the Amdahl's law, Gustafson's law exists. I though that there might be some law which states the relation between CPU Hz's and network speed: maximum network speed after which no ...
3
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1answer
2k views

Custom .NET apps and clustering

So for a clustered environment - how would this work with your apps? what about your own custom .NET apps? Would there be a special way to develop them? I know that you can say create a simple Hello ...
0
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1answer
146 views

Clustering and custom applications

So lets say we have a clustered environment setup. We have a cluster SQL Server (I don't know exactly how its done but lets just say its been done for the sake of argument). Now if a website or ...
15
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3answers
16k views

How to design highly scalable web services in Java?

I am creating some Web Services that would have 2000 concurrent users. The services are offered for free and are hence expected to get a large user base. In the future it may be required to scale up ...
4
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1answer
1k views

Grouping numbers to minimize group-means

I need to find a way or an algorithm that groups members of a given data set (of positive integers) so that the difference between group means is minimized (not maximized, as usual). There are two ...
19
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3answers
20k views

Efficient graph clustering algorithm

I'm looking for an efficient algorithm to find clusters on a large graph (It has approximately 5000 vertices and 10000 edges). So far I am using the Girvan–Newman algorithm implemented in the JUNG ...
5
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2answers
2k views

How to implement a lightweight clustered architecture for a distributed application

I currently have a distributed application that runs on multiple embedded PCs. The whole application is composed of one master server and several nodes. Each node is an embedded PC that runs Windows 7 ...
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2answers
765 views

Mahout's Flexibility for generating recommendations

I am currently working on a system that will generate product recommendations like those on Amazon: "People who bought this also bought this.." This is how I plan to do it: Process the data using ...
1
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1answer
135 views

Apply for supercomputing time

For testing and running some very intensive C++ number crunching applications, we need to apply for supercomputing time. I would like to get feedback and opinions from you; which calls do you follow, ...
0
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1answer
395 views

Transactional database and Datawarehouse on the same Postgresql cluster?

Is it conceptually feasible to have on a Postgresql Cluster a transactional database and at the same time a datawarehouse that would get feeded by the transactional database ?
3
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2answers
301 views

How does one make a cluster capable program?

In cluster computing, there seems to be two options: task redirection and task splitting. Task redirection seems easy enough, you just have the master dispatch the small calls to other nodes in the ...