I am wondering conceptually how load-balancing works on the EJB-level (not web session replication) with Java EE containers like Glassfish. From what I have gleaned your remote interface is a proxy that delegates your call to one of many servers you may have in an environment. If things fail are they supposed to be able to "finish" o...
I'm working on a multi-threaded program where I have a number of worker threads performing tasks of unequal length. I want to load-balance the tasks to ensure that they do roughly the same amount of work. For each task Ti I have a number ci which provides a good approximation to the amount of work that is required for that task. ...
My boss wants to have a system that takes into concern of continent wide catastrophic event. He wants to have two servers in US and two servers in Asia (1 login server and 1 worker server in each continent). In the event that earthquake breaks the connection between the two continents, both should work alone. When the connection is rev...
Hi, I have to create a .net web application which would run on more than one front end server which are load balanced. Now I have to use some third party api which is not thread safe so only one thread should call the API at a time so I have to use some syncronization machanism like lock or mutex which provide syncronisation within the p...
I'm trying to understand how to create CRM Organization on Load Balancing network. I've three web servers (Web01, Web 02, Web03); three application servers (App01, App02, App03) and a SQL Server (SQL01). I already have Load Balancer setup and there is already one organizaiton setup by someone on all web servers. This organization is I...
Hi, We have an application running on a loadbalanced environment, let say webserver A and B. The loadbalancing is on the HTTP level, so the loadbalancer directs each user request to one of both webservers. The scope of the repositories in the application is managed by the spring.net container, and the application relies on data that ca...
I have a library, written in C#, containing one method: Response CalculateSomething(Request); The execution time of this method is relatively large, and there are a lot of responses that should be processed. I want to use a "cluster", spread this DLL to different machines (nodes) in this "cluster" and write some controller that will d...
I have a few web servers behind an Amazon EC2 load balancer. I'm using TCP balancing on port 80 (rather than HTTP balancing). I have a client polling a Web Service (running on all web servers) for new items every few seconds. However, the client seems to stay connected to one server and polls that same server each time. I've tried usin...
I am building a web application with Spring Security that will live on Amazon EC2 and use Amazon's Elastic Load Balancers. Unfortunately, ELB does not support sticky sessions, so I need to ensure my application works properly without sessions. So far, I have setup RememberMeServices to assign a token via a cookie, and this works fine, b...
We are having two load balancing server. In that we have hosted a asp.net 3.5 application right now we are using request userhostaddress to get visitor ip but it is giving load balancer ip instead of real ip. Can anyone have code for this. ...
We are using two load balancing server for asp.net site in that we have a functionality which will create a receipt of order in pdf using abcpdf component it was working fine without load balancing server and but when we move it to load balancing server it is giving errors like. A generic error occurred in GDI. I have given full rights t...
Hi all, I've set up load balancing using Apache, Tomcat through ajp connector. Here the config Apache/httpd.conf BalancerMember ajp://10.0.10.13:8009 route=osmoz-tomcat-1 retry=5 BalancerMember ajp://10.0.10.14:8009 route=osmoz-tomcat-2 retry=5 < Location /> Allow From All ProxyPass balancer://tomcatservers/ stickysession=JSE...
Scenario Multiple application servers host web services written in Java, running in SpringSource dm Server. To implement a new requirement, they will need to query a read-only PostgreSQL database. Issue To support redundancy, at least two PostgreSQL instances will be running. Access to PostgreSQL must be load balanced and must auto-...
I have a PHP program that has been written keeping in mind a single server, so there are inherent limitation to how much it can handle. For example, the developer says that his current webhosting service provides him with "50 MySQL connections" which he interprets as that only 50 people can be simultaneously logged onto it. What do we n...
My web app has been chugging along just great in Production for years with one App server and one Web server. Now we're moving to a multi-server environment with 2 App and 3 Web servers. I have enough time to make changes before the go-live. As a Developer, what considerations should I take into account from coding, deployment, and arch...
So it's easy to load balance an ASP.NET web application. You set up a load balancer between two servers, and if the web server isn't responding on Port 80, it won't receive requests. Are there any proven techniques for doing this for a C# console application or Windows service that takes actions of its own volition? Are there any fram...
Why is it that I can find lots of information on "work stealing" and nothing on "work shrugging" as a dynamic load-balancing strategy? By "work-shrugging" I mean pushing surplus work away from busy processors onto less loaded neighbours, rather than have idle processors pulling work from busy neighbours ("work-stealing"). I think the ...
After a ton of reading in books and on the web, I have noticed hints of information that WCF and MSMQ can be used in achieving high throughput. The information I have seen mentions using multiple WCF services in a farm that reads from a single MSMQ queue. The problem is that I have found paragraphs here and there that mentions that hig...
I've been investigating different scheduling algorithms for a thread pool I am implementing. Due to the nature of the problem I am solving I can assume that the tasks being run in parallel are independent and do not spawn any new tasks. The tasks can be of varying sizes. I went immediately for the most popular scheduling algorithm "wo...
Hi, I have an environment where in there are two tomcat instances running the same application. What I would need is an apache load balancing the url requests to these tomcat instances using the mod_rewrite rules. I know that we can do this with mod_jk already but have observed that the mod_jk s an overhead in terms of performance so f...