I think all Cloud plugin developers will be glad to know about Cloud API problems and their changes. Really difficult to follow massive changes in core. Any comments about docker-plugin will be appreciated. Also it will be very cool if you review https://github.com/jenkinsci/jenkins/pull/1448
On Thursday, April 23, 2015 at 11:21:18 AM UTC+3, Stephen Connolly wrote: > > Carlos, please sync up with me to get my full rant on the deficiencies of > the Cloud API. I can point you to our "best" implementations (which sadly > for the community are closed source - not my call) > > FWIW the current Cloud API is IMHO a crappy extension point and it is > almost impossible for anyone to implement correctly. There is, to my > knowledge, no correct implementation of the Jenkins Cloud API. The "best" > implementations I am aware of are currently closed source but IMHO it's no > big loss to the community as even those have issues. > > The changes I made in 1.607 correct for some of the issues, but w.r.t. the > Cloud API it's more lipstick on a pig. > > On my backlog is to replace the Cloud API with a new and much easier to > implement extension point. I gave myself the hooks to do that in either > 1.592 or 1.588 and it should be possible to implement as a plugin rather > than waiting for changes in core. > > Every single cloud implementation has issues as soon as you start to put > it under load. With oc-cloud I am able to mask a large chunk of the issues > by virtue of doing the required coordination from Operations Center and by > doing the state management in a local transaction database... but all of > that is far far too much overhead to ask every cloud implementation to do. > Jenkins *should* be doing it for the cloud implementer... > > In short, I believe what the docker-plugin is doing is "a severely > sub-optimal path" and it only gets away with it when under light-medium > load. I can cause it to "go bad" with some of my stress tests that I used > to develop the fixes for 1.607 > > On 23 January 2015 at 17:33, Carlos Sanchez <[email protected] > <javascript:>> wrote: > >> Hi! >> >> I'm creating the Kubernetes plugin [1] to start slaves in Kubernetes or >> Google Container Engine, which basically means launching Docker containers >> across multiple hosts with just one API. >> Some background: Kubernetes allows launching individual containers (Pods) >> or creating a ReplicationController, which accepts a Pod template and a >> number of how many containers you want to run, and can be resized >> dynamically, a pool of containers. >> >> Initially I though about implementing the plugin using a >> ReplicationController and resizing it as new slaves are needed, but seems >> that Jenkins operation doesn't fit well with this idea. It would prevent >> killing specific slaves, it would just be a pool. So I went ahead and moved >> to launch Pods one by one. >> >> The issue I have now is about initialization time, where the container is >> not accepting connections until the image is downloaded and started. The >> Docker plugin has this comment [2] >> >> // Docker instances may have a long init script. If we declare >> // the provisioning complete by returning without the connect >> // operation, NodeProvisioner may decide that it still wants >> // one more instance, because it sees that (1) all the slaves >> // are offline (because it's still being launched) and >> // (2) there's no capacity provisioned yet. >> // >> // deferring the completion of provisioning until the launch >> // goes successful prevents this problem. >> slave.toComputer().connect(false).get(); >> >> Should I do the same? >> >> There is also the issue that Kubernetes would be better suited for swarm >> slaves. Opening ssh or ports in each pod is more complicated than just >> doing the connection to the master from the container. >> >> Thanks! >> >> [1] >> https://github.com/carlossg/jenkins-kubernetes-plugin/blob/master/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java >> [2] >> https://github.com/jenkinsci/docker-plugin/blob/master/src/main/java/com/nirima/jenkins/plugins/docker/DockerCloud.java#L239 >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Jenkins Developers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/jenkinsci-dev/5e641038-b83b-4901-83a8-4bb54255498a%40googlegroups.com >> >> <https://groups.google.com/d/msgid/jenkinsci-dev/5e641038-b83b-4901-83a8-4bb54255498a%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "Jenkins Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jenkinsci-dev/0e6ca23c-9fc2-41c0-9e02-b555c0d1bde7%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
