thanks for the link it's so helpful On Tue, Jan 24, 2017 at 7:31 AM, Navin Ipe <[email protected]> wrote:
> More specifically, the bottom of this page explains what the numbers mean > in terms of tasks and executors: http://nrecursions.blogspot. > in/2016/05/more-concepts-of-apache-storm-you-need.html > > On Mon, Jan 23, 2017 at 5:28 PM, sam mohel <[email protected]> wrote: > >> really thanks for your help >> >> On Mon, Jan 23, 2017 at 1:59 PM, Arun Mahadevan <[email protected]> wrote: >> >>> There is no magic number, it depends on the specific problem you are >>> trying to solve. You start with some reasonable value for the parallelism >>> and tune it based on your requirements. You could also start with a higher >>> number of “tasks” than the parallelism and then you can rebalance your >>> topology and adjust parallelism on the fly to scale up or down. >>> >>> >>> >>> See the slides from Taylor’s “Scaling Storm” presentation, you might >>> find it useful - http://www.slideshare.net/ptgo >>> etz/scaling-apache-storm-strata-hadoopworld-2014 >>> >>> >>> >>> >>> >>> *From: *sam mohel <[email protected]> >>> *Reply-To: *"[email protected]" <[email protected]> >>> *Date: *Monday, January 23, 2017 at 4:58 PM >>> >>> *To: *"[email protected]" <[email protected]> >>> *Subject: *Re: simple question about grouping >>> >>> >>> >>> Many thanks , but how and when can i decide that this number is perfect >>> form me or not ? >>> >>> >>> >>> On Mon, Jan 23, 2017 at 1:27 PM, Arun Mahadevan <[email protected]> >>> wrote: >>> >>> > builder.setBolt("MyBolt", new MyBolt(), 4).shuffleGrouping("MySpout"); >>> i found this example but couldn't know why he use number 4 ? >>> >>> >>> >>> This is the “parallelism hint” (the number of threads) for “MyBolt”. So >>> in your example there will be 4 threads executing “MyBolt” across the >>> workers in your cluster and the tuples from “MySpout” would be randomly >>> distributed across all of the 4 instances of your bolt. >>> >>> >>> >>> Also see http://storm.apache.org/releases/1.0.1/Understanding-the-par >>> allelism-of-a-Storm-topology.html >>> >>> >>> >>> >>> >>> >>> >>> *From: *sam mohel <[email protected]> >>> *Reply-To: *"[email protected]" <[email protected]> >>> *Date: *Monday, January 23, 2017 at 4:47 PM >>> *To: *"[email protected]" <[email protected]> >>> *Subject: *Re: simple question about grouping >>> >>> >>> >>> excuse me , if i have single spout and single bolt and the bolt doing 2 >>> process so can i do like this >>> builder.setSpout("MySpout", new mySpout(), 1); >>> builder.setBolt("MyBolt", new MyBolt(), 4).shuffleGrouping("MySpout"); i >>> found this example but couldn't know why he use number 4 ? >>> >>> >>> >>> On Mon, Jan 23, 2017 at 1:13 PM, sam mohel <[email protected]> wrote: >>> >>> thanks for replying >>> >>> >>> >>> On Mon, Jan 23, 2017 at 1:14 PM, Arun Mahadevan <[email protected]> >>> wrote: >>> >>> >>> >>> Grouping makes sense only when you have more than one task for a bolt. >>> If your bolt has more than one task, then the grouping will decide how the >>> tuples from the spout are distributed to the individual tasks of the bolt. >>> (shuffe = random, fields = keyed on some field and so on). >>> >>> >>> >>> See http://storm.apache.org/releases/current/Concepts.html >>> >>> >>> >>> Thanks, >>> >>> Arun >>> >>> >>> >>> >>> >>> *From: *sam mohel <[email protected]> >>> *Reply-To: *"[email protected]" <[email protected]> >>> *Date: *Monday, January 23, 2017 at 3:09 PM >>> *To: *"[email protected]" <[email protected]>, " >>> [email protected]" <[email protected]> >>> *Subject: *simple question about grouping >>> >>> >>> >>> i have text file contains data . size of this file is 3.5 MB . My >>> topology consists of one spout and one bolt so is that possible to make all >>> processing in one bolt and in this case what is the role of grouping here ? >>> >>> Thanks in advance >>> >>> >>> >>> >>> >>> >>> >> >> > > > -- > Regards, > Navin >
