Re: Load-balancing between service instances
Simon Laws wrote: On 8/9/07, Maciek Chociej [EMAIL PROTECTED] wrote: Hello, Recently I've been investigating the same thing. I'm trying to rebuild our in-house SOA platform with the use of Tuscany. What I am lacking is clustering, dynamic lookup and load balancing of service providers. I don't think I need that for local wiring, so I just focused on providing those over the ws binding. From what I see right now it is possible to do that rather gracefully in a number of ways. For example on the remote side, you can use your web container's clustering scheme. For example Tomcat clusters might balance request to the axis servlets responsible for the ws.binded services, the downside of this is that the balancing gets out of Tuscany's control. On the other hand, on the local side (which I find much nicer) I've tampered a little with the ws axis binding and it should be easily possible to inject a UDDI or similar ws lookup into the ReferenceBindingProvider or to build a 'lookup' version extending the axis one. I'm rather new to Tuscany so any comments appreciated. Cheers Maciek Olivier Collard wrote: Hi, I'm wondering how I could implement load-balancing with Tuscany. Basically, I would need the ability to configure component X to talk to multiple instances of another component Y. Ideally, this would be like 'wiring' a reference to multiple instances of component Y, running either locally or remotely. Would I need to write some kind of extension for this? Thanks, O. Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Hi This is an interesting thread. The easy answer is that you are both right that we haven't addressed load balancing or clustering directly just yet. We are working on a first step at the moment which might make some of this easier. That is the ability to have an SCA domain run across multiple nodes (JVMs). We have had a very simple version of this for a while and we are bringing it up again now on top of the new wiring mechanism and new SCA binding. The basic idea here is that you have parts of the domain, i.e. component services, running on separate nodes and Tuscany is able to locate which node is running which service. So this could be considered load balancing in that it allows you to distribute your application across a number of nodes but it's not load balancing in the sense that Olivier mentioned. I.e. spreading the load on a single component/service. I think Maciek is on the right track though. I like the ideas about having a new binding that is able to provide this feature within a Tuscany domain with reference to some registry of services. It would certainly be interesting to do this with a binding based on the web services binding with, as suggested, suitable logic to look up target services and pick one from the list of returned endpoints. Running inside a clustered container should also be a possibility. A you say we would expect the clustering to be outside Tuscany's control in this case and we would have to engineer for the registry of service endpoints to have the address of the head node rather than the individual servers where Tuscany is running components in the cluster. We would also need to look out for session replication issues. Either of you interested in doing some work on this? Regards Simon So I guess there's at least two options: [a] leverage the Tomcat clustering / load-balancing capabilities (make sure that Tuscany works OK in that environment) [b] write a binding extension, or tamper with an existing one :) to add load-balancing in Tuscany If any of you are interested in doing some work on this, here are a few pointers: - a simple distributed sample, which could be used as a starting point to demonstrate some load-balancing http://svn.apache.org/repos/asf/incubator/tuscany/java/sca/samples/calculator-distributed/ - the Tuscany SCA default binding, which uses a simple registry shared on the network to record endpoints of services as they start, and to resolve these endpoints later the binding extension http://svn.apache.org/repos/asf/incubator/tuscany/java/sca/modules/binding-sca-axis2/ the distributed registry http://svn.apache.org/repos/asf/incubator/tuscany/java/sca/modules/distributed http://svn.apache.org/repos/asf/incubator/tuscany/java/sca/modules/distributed-impl/ We're just at the beginning of implementing this so it's the right time to jump in if you want to add some load-balancing :) -- Jean-Sebastien - To unsubscribe, e-mail: [EMAIL
Re: Load-balancing between service instances
Hello, Recently I've been investigating the same thing. I'm trying to rebuild our in-house SOA platform with the use of Tuscany. What I am lacking is clustering, dynamic lookup and load balancing of service providers. I don't think I need that for local wiring, so I just focused on providing those over the ws binding. From what I see right now it is possible to do that rather gracefully in a number of ways. For example on the remote side, you can use your web container's clustering scheme. For example Tomcat clusters might balance request to the axis servlets responsible for the ws.binded services, the downside of this is that the balancing gets out of Tuscany's control. On the other hand, on the local side (which I find much nicer) I've tampered a little with the ws axis binding and it should be easily possible to inject a UDDI or similar ws lookup into the ReferenceBindingProvider or to build a 'lookup' version extending the axis one. I'm rather new to Tuscany so any comments appreciated. Cheers Maciek Olivier Collard wrote: Hi, I'm wondering how I could implement load-balancing with Tuscany. Basically, I would need the ability to configure component X to talk to multiple instances of another component Y. Ideally, this would be like 'wiring' a reference to multiple instances of component Y, running either locally or remotely. Would I need to write some kind of extension for this? Thanks, O. Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Load-balancing between service instances
On 8/9/07, Maciek Chociej [EMAIL PROTECTED] wrote: Hello, Recently I've been investigating the same thing. I'm trying to rebuild our in-house SOA platform with the use of Tuscany. What I am lacking is clustering, dynamic lookup and load balancing of service providers. I don't think I need that for local wiring, so I just focused on providing those over the ws binding. From what I see right now it is possible to do that rather gracefully in a number of ways. For example on the remote side, you can use your web container's clustering scheme. For example Tomcat clusters might balance request to the axis servlets responsible for the ws.binded services, the downside of this is that the balancing gets out of Tuscany's control. On the other hand, on the local side (which I find much nicer) I've tampered a little with the ws axis binding and it should be easily possible to inject a UDDI or similar ws lookup into the ReferenceBindingProvider or to build a 'lookup' version extending the axis one. I'm rather new to Tuscany so any comments appreciated. Cheers Maciek Olivier Collard wrote: Hi, I'm wondering how I could implement load-balancing with Tuscany. Basically, I would need the ability to configure component X to talk to multiple instances of another component Y. Ideally, this would be like 'wiring' a reference to multiple instances of component Y, running either locally or remotely. Would I need to write some kind of extension for this? Thanks, O. Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Hi This is an interesting thread. The easy answer is that you are both right that we haven't addressed load balancing or clustering directly just yet. We are working on a first step at the moment which might make some of this easier. That is the ability to have an SCA domain run across multiple nodes (JVMs). We have had a very simple version of this for a while and we are bringing it up again now on top of the new wiring mechanism and new SCA binding. The basic idea here is that you have parts of the domain, i.e. component services, running on separate nodes and Tuscany is able to locate which node is running which service. So this could be considered load balancing in that it allows you to distribute your application across a number of nodes but it's not load balancing in the sense that Olivier mentioned. I.e. spreading the load on a single component/service. I think Maciek is on the right track though. I like the ideas about having a new binding that is able to provide this feature within a Tuscany domain with reference to some registry of services. It would certainly be interesting to do this with a binding based on the web services binding with, as suggested, suitable logic to look up target services and pick one from the list of returned endpoints. Running inside a clustered container should also be a possibility. A you say we would expect the clustering to be outside Tuscany's control in this case and we would have to engineer for the registry of service endpoints to have the address of the head node rather than the individual servers where Tuscany is running components in the cluster. We would also need to look out for session replication issues. Either of you interested in doing some work on this? Regards Simon
