and, yes, I think that picture is a bit misleading, though in the following paragraph it has mentioned that
“ Because the driver schedules tasks on the cluster, it should be run close to the worker nodes, preferably on the same local area network. If you’d like to send requests to the cluster remotely, it’s better to open an RPC to the driver and have it submit operations from nearby than to run a driver far away from the worker nodes. " -- Nan Zhu On Wednesday, March 26, 2014 at 9:59 AM, Nan Zhu wrote: > master does more work than that actually, I just explained why he should set > MASTER_IP correctly > > a simplified list: > > 1. maintain the worker status > > 2. maintain in-cluster driver status > > 3. maintain executor status (the worker tells master what happened on the > executor, > > > > -- > Nan Zhu > > > > On Wednesday, March 26, 2014 at 9:46 AM, Yana Kadiyska wrote: > > > Nan (or anyone who feels they understand the cluster architecture well), > > can you clarify something for me. > > > > From reading this user group and your explanation above it appears that the > > cluster master is only involved in this during application startup -- to > > allocate executors(from what you wrote sounds like the driver itself passes > > the job/tasks to the executors). From there onwards all computation is > > done on the executors, who communicate results directly to the driver if > > certain actions (say collect) are performed. Is that right? The only > > description of the cluster I've seen came from here: > > https://spark.apache.org/docs/0.9.0/cluster-overview.html but that picture > > suggests there is no direct communication between driver and executors, > > which I believe is wrong (unless I am misreading the picture -- I believe > > Master and "Cluster Manager" refer to the same thing?). > > > > The very short form of my question is, does the master do anything other > > than executor allocation? > > > > > > On Wed, Mar 26, 2014 at 9:23 AM, Nan Zhu <zhunanmcg...@gmail.com > > (mailto:zhunanmcg...@gmail.com)> wrote: > > > what you only need to do is ensure your spark cluster is running well, > > > (you can check by access the Spark UI to see if all workers are displayed) > > > > > > then, you have to set correct SPARK_MASTER_IP in the machine where you > > > run spark-shell > > > > > > The more details are : > > > > > > when you run bin/spark-shell, it will start the driver program in that > > > machine, interacting with the Master to start the application (in this > > > case, it is spark-shell) > > > > > > the Master tells Workers to start executors for your application, and the > > > executors will try to register with your driver, > > > > > > then your driver can distribute tasks to the executors, i.e. run in a > > > distributed fashion > > > > > > > > > Best, > > > > > > -- > > > Nan Zhu > > > > > > > > > On Wednesday, March 26, 2014 at 9:01 AM, Sai Prasanna wrote: > > > > > > > Nan Zhu, its the later, I want to distribute the tasks to the cluster > > > > [machines available.] > > > > > > > > If i set the SPARK_MASTER_IP at the other machines and set the > > > > slaves-IP in the /conf/slaves at the master node, will the interactive > > > > shell code run at the master get distributed across multiple machines > > > > ??? > > > > > > > > > > > > > > > > > > > > > > > > On Wed, Mar 26, 2014 at 6:32 PM, Nan Zhu <zhunanmcg...@gmail.com > > > > (mailto:zhunanmcg...@gmail.com)> wrote: > > > > > what do you mean by run across the cluster? > > > > > > > > > > you want to start the spark-shell across the cluster or you want to > > > > > distribute tasks to multiple machines? > > > > > > > > > > if the former case, yes, as long as you indicate the right master URL > > > > > > > > > > > > > > > if the later case, also yes, you can observe the distributed task in > > > > > the Spark UI > > > > > > > > > > -- > > > > > Nan Zhu > > > > > > > > > > > > > > > On Wednesday, March 26, 2014 at 8:54 AM, Sai Prasanna wrote: > > > > > > > > > > > Is it possible to run across cluster using Spark Interactive Shell ? > > > > > > > > > > > > To be more explicit, is the procedure similar to running standalone > > > > > > master-slave spark. > > > > > > > > > > > > I want to execute my code in the interactive shell in the > > > > > > master-node, and it should run across the cluster [say 5 node]. Is > > > > > > the procedure similar ??? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > Sai Prasanna. AN > > > > > > II M.Tech (CS), SSSIHL > > > > > > > > > > > > Entire water in the ocean can never sink a ship, Unless it gets > > > > > > inside. > > > > > > All the pressures of life can never hurt you, Unless you let them > > > > > > in. > > > > > > > > > > > > > > > > > > > > > -- > > > > Sai Prasanna. AN > > > > II M.Tech (CS), SSSIHL > > > > > > > > Entire water in the ocean can never sink a ship, Unless it gets inside. > > > > All the pressures of life can never hurt you, Unless you let them in. > > > > > >
