distributed

Can i use Distributed Database for a crawler?

Hey friends can i use a distributed DB for my WebCrawler,what all are the available Open Source Distributed Databases?? can i use MySQL as my distributed DB? how amount of data can be stored? ...

python package for distributed auction simulation

Hi, Does anyone know of a package that allows for a distributed agent-based double auction simulation? I've looked at SimPy, but that's a discrete-event simulator and difficult to get working in a distributed fashion. regs, Vivek ...

Questions about Java EE ?

In wiki, it says: Java Platform, Enterprise Edition [...] to deploy [...] distributed, multi-tier Java software, based largely on modular components running on an application server. As far as i know, distributed means "multiple computers" which is equal to "multiple servers", so why it says in the end "running on an application server...

building using multiple machines

Hi All I have a huge Windows C++ project that takes a lot of time to be compiled. Do you know if there is some FREE tool being able to build using multiple pc connected together? Do you know if there is some free tool doing the same in Linux using GCC? At least there is something that I can do to split the work myself? Thanks ...

Is there an open-source Chord DHT implementation for .NET?

I'm looking for a high level, decentralized, robust, scalable lookup/message passing package I can use with .NET 2.0. I believe Chord is the correct base algorithm for this use. Explicit, proven time guarantees are a must (e.g. lookups resolve in at most log(n) messages or steps). Chord routing looks sufficient. Suppose I want to prov...

MapReduce skipping keys?

I'm running a local, single-system test using Qizmt of a simple MapReduce operation. At the end of the 'Map' phase I am calling: output.Add(rKey, rValue); This is called let's say a million times, and the keys are 1,2,3,4,5,6 etc - each unique (I'm just testing, after all). I've checked that this is happening as intended. It is. The f...

Short unique values with Amazon Web Services

I'm working on a system conceptually similar to an URL shortener like bit.ly -- a client sends in a bit of data and the system returns a very short URL to represent it (a base URL + a token representing the data). Ideally, it would start with the shortest token possible (maybe 4 or 5 alphanumeric characters) and move on to longer tokens ...

Multi-tier vs Distibuted ?

Multi-tier and/or ditstributed apps, do they have the same meaning ? When we talk about layers in these apps, is it physical layers (database, browser, web server,...) or logical layers (data access layer, business layer,...) ? ...

PHP: MYSQL-based session sharing on different machine

Hi all, I have an app sits on machine A (solaris.example.com) and same apps sits on machine B (rhodes.example.com), these two machines are connected to same MYSQL database which has session table on it. I've implemented my own session handler so it saves to the database instead of saving it to the files and this works fine. My questio...

Finding out deployment machine you are on in code (Rails)

Hi folks! My rails app is deployed to several machines. I need each machine to run different cron jobs (it will be a disaster if they all run the job). How do i tell my script which machine it is currently on? I am using the whenever gem, and i am thinking of adding the condition in the schedule.rb Example: My deploy/production.rb r...

distributed unit testing/scenario based unit testing with boost.test

Hello, I am developing unit test cases for an application using Boost.test libraries. There are certain APIs which can directly be tested. But, there are APIs which require interaction between test machines. So for example, execution of a certain API in machine 1 should trigger an API in test machine 2 and its response needs to be use...

java distributed database data sharing

I want applications to share certain database data. I want one application to retrieve and display certain table views of data produced by another application. Do you know of any open source technologies that I can use for such a distributed solution? ...

Pass by reference problem in RMI ?

Hi, can somebody please tell me where i m wrong why this RMI chat application not working,the goal is to achieve decoupleing between client, server and logic by remote objects or serialized objects. import javax.swing.*; import java.awt.event.*; import java.rmi.*; import java.rmi.server.*; public class ChatClient1...

Java IoC : distributed configuration

I'm building a J2EE application in which I want to allows plugins. I'm fairly convince of the goodness of IoC framework, and so the application will have one to manage services. Now, I want to allows plugins to be added as simple JAR dropped in the classpath + perhaps a simple configuration file to edit to activate them, in no way some...

Manage session within distributed application

Hello everybody, I'm working on distributed web application and we decided to separate web module from business services to make it more scalable. Here is the situation: We have one server instance that keeps web application (Controllers, JSPs, etc) and lots of server instances with business services. If web application needs any data ...

Real-life grid/distributed-computing application source codes etc..?

Hi, I started-off by making a chess AI engine (simple min-max), and ended-up trying to develop something like BOINC, but MUCH more lighter/re-distributable and most importantly decentralized. I was searching for sample applications to run on it and test it, but all I could find was some "impossible to understand" pi value calculators and...

How can I tie togeather extra space on Macintosh desktops with a distributed filesystem?

I have access to a bunch of Mac desktops, the hard drives of which are under-utilized. I want to set up a distributed filesystem to gang them together into one large virtual volume. The server has to be able to run as a normal user. I've tried PVFS2, but it's designed for Linux and isn't running well on OSX (hangs the clients on write)....

Distributed log system

Hi, I need to store logs in a distributed file system. Let's say that I have many types of logs. Each log type is recorded in file. But this file can be huge, so it must be distributed across many nodes (with replication for data durability). These files must support append/get operations. Is there a distributed system that achieves ...

How to disribute and maintain java/scala program over a Linux cluster ?

I have a small cluster of Linux machines and an account on all of them. I have ssh access to all of them with no-password login. How can I use actors or other Scala's concurrency abstraction to achieve distribution ? What is the simplest path? Does some library can distribute the processes for me? The computers are unreliable, they can...

Automated distribution of processes through SSH.

I can launch processes on one of 20 machines using SSH (there is a shared file system). But I need to constantly watch these machines as they may be turned off/on at random times. I've hacked a shell loop but it is unreliable. Is there a program that could do that for me? ...