Re: [Engine-devel] Task cancelation feature

----- Original Message ----- There are also a few requirements from gluster perspective that may need enhancements in vdsm as well as engine. - Tasks are created and managed by glusterfs and not by vdsm. - Gluster tasks are not bound to a particular host, but are cluster-wide, and their status can be checked from any of the hosts of the cluster. - Concept of SPM does not come into picture in case of gluster clusters/hosts - Apart from starting, aborting and checking status, some of the gluster tasks support additional actions like pause, resume and commit. Based on some of the telephonic conversations with maintainers of engine and vdsm, we were planning to enhance the existing task management as follows: - Enhance the getAllTasks verb in vdsm to accept one or more tags for filtering tasks. (http://gerrit.ovirt.org/7579) - Currently all tasks created in vdsm through requests from engine have the 'spm' tag as they are SPM tasks. - Introduce a new field, say task_target in engine, which indicates what kind of a task it is. Possible values: - SPM (SPM tasks) - CLUSTER (cluster-wide tasks e.g. gluster tasks) - HOST (tasks specific to a particular host e.g. format a disk on a host) - Enhance the async task manager in engine, to fetch details of all types of tasks, by sending appropriate tags to the new getAllTasks verb. (At present it fetches only SPM tasks) - Once all the tasks are fetched, rest of the processing (updating status) remains same as before I would like to know whether we should stop working on above approach in case the new design is coming up immediately. If yes, we should make sure that the new design is capable of handling the gluster tasks as well. In case it is too far in the future, 1) We will start working with above approach. Any comments/suggestions/concerns are welcome. 2) Instead of focusing on just 'cancellation', we should try and come up with a more generic approach which can help in easily supporting more actions like pause, resume, commit, etc. (I haven't yet gone through the feature page, and please pardon me if this is already taken care)