What dictates the number of Mappers and reducers that are run in MapReduce?
What dictates the number of Mappers and reducers that are run in MapReduce?
Homework Answers
`Hey,
Note: Brother in case of any queries, just comment in box I would be very happy to assist all your queries
No of mappers is completely depends on input format you use. For example TextInputFormat splits data based on lines. If you have 1000 lines in your input data, it will create 1000 splits. Each split is termed to be a mapper. So you cannot have a hold on number of mappers in your job.
When it comes to reducer you can always specify number of reducers you want to use in the job configuration. For example you can specify 5reducers for your job. Partitioner will decide which reducer will get what data.
When it comes to number of jobs run in parallel(either it is a mapper or reducer job), it completely depends on your cluster availablity.
Kindly revert for any queries
Thanks.
Add Answer to:
What dictates the number of Mappers and reducers that are run in
MapReduce?
Question 1 (50) MapReduce For each problem, provide test data (as input files), MapReduce programs, and...
Question 1 (50) MapReduce For each problem, provide test data (as input files), MapReduce programs, and running results (screen shoots) on Hadoop i) Write a program to read input file (an integer number per line) and remove duplicated numbers ii) When data are transmitted from map to reduce, <key, value will be automatically sorted in an ascending order. Write a program that can read input file (an integer number per line) and write them out in a descending order.
Hadoop MapReduce program which outputs the number of words that start with each letter. This means...
Hadoop MapReduce program which outputs the number of words that start with each letter. This means that for every letter we want to count the total number of words that start with that letter. In your implementation ignore the letter case, i.e., consider all words as lower case. You can ignore all non-alphabetic characters.
MapReduce and Hadoop (a) Explain the difference between map and reduce tasks in the MapReduce framework. (b) How does the Hadoop framework ensure that no reduce tasks can begin until all map tasks hav...
MapReduce and Hadoop (a) Explain the difference between map and reduce tasks in the MapReduce framework. (b) How does the Hadoop framework ensure that no reduce tasks can begin until all map tasks have finished? (c) When a worker node fails in Hadoop, its tasks are reassigned to other workers. What guarantees that the data being processed by the failed node is available to these other workers?
American political culture dictates the type of policies which can be adopted in the U.S. This...
American political culture dictates the type of policies which can be adopted in the U.S. This means that American healthcare/education/foreign/family policies will look very different from those of other countries. What policies do you think other countries could borrow from the U.S.? What policies do you think the U.S. could borrow from other countries?
In the transition from the short run to the long run, the number of firms in...
In the transition from the short run to the long run, the number of firms in a competitive industry is a. fixed. b. increasing at a constant rate. c. decreasing. d. able to adjust to market conditions.
What does a run-time analysis usually countS pts a. The number of arithmetic and other operations...
What does a run-time analysis usually countS pts a. The number of arithmetic and other operations required fot the b. The number of megabytes required for the program to run c. The number of seconds required for the program to run. d. The number of seconds plus the number of megabytes Total 100 points, 30 ins and other operations required for the program to rn 2. What do we call an input that results in the longest execution timet a....
In monopolistic competition, what market force works against short-run profits? Increasing the number of sellers shifts...
In monopolistic competition, what market force works against short-run profits? Increasing the number of sellers shifts supply. The availability of substitutes shifts demand. The availability of substitutes shifts supply. Increasing the number of sellers shifts demand.
A type of robot is able to run more than one program simultaneously. The number of...
A type of robot is able to run more than one program simultaneously. The number of programs to be run varies depending on where the robot is used. A large study of robots of this type found that the distribution of the number of programs being run is summarised below. Number of programs | 1 | 2 | 3 | 4 Probability 0.5 0.25 0.15 0.1 (a) Determine the expected number of programs being run simultaneously on a randomly selected...
What is the shape of the AS in the short run and the long run? a....
What is the shape of the AS in the short run and the long run? a. AS is relatively flat in the short run, but steeper in the long run. b. AS is relatively steep in the short run, but flatter in the long run. c. AS is relatively steep in both the short and long run. d. AS is relatively flat in both the short and long run
Hannah and Sam run Moretown Makeovers, a home remodeling business. The number of square feet they...
Hannah and Sam run Moretown Makeovers, a home remodeling business. The number of square feet they can remodel in a week is described by the Cobb-Douglas production function Q=F(L,K) Q=10L0.5K0.5, where L is their number of workers and K is units of capital. The wage rate is $200 per week and a unit of capital costs $200 per week. Suppose that when initially producing 100 square feet a week, they use 10 units of capital. a. What is their short-run...
Question 1 (50) MapReduce For each problem, provide test data (as input files), MapReduce programs, and running results (screen shoots) on Hadoop i) Write a program to read input file (an integer number per line) and remove duplicated numbers ii) When data are transmitted from map to reduce, <key, value will be automatically sorted in an ascending order. Write a program that can read input file (an integer number per line) and write them out in a descending order.
American political culture dictates the type of policies which can be adopted in the U.S. This means that American healthcare/education/foreign/family policies will look very different from those of other countries. What policies do you think other countries could borrow from the U.S.? What policies do you think the U.S. could borrow from other countries?
What does a run-time analysis usually countS pts a. The number of arithmetic and other operations required fot the b. The number of megabytes required for the program to run c. The number of seconds required for the program to run. d. The number of seconds plus the number of megabytes Total 100 points, 30 ins and other operations required for the program to rn 2. What do we call an input that results in the longest execution timet a....
In monopolistic competition, what market force works against short-run profits? Increasing the number of sellers shifts supply. The availability of substitutes shifts demand. The availability of substitutes shifts supply. Increasing the number of sellers shifts demand.
A type of robot is able to run more than one program simultaneously. The number of programs to be run varies depending on where the robot is used. A large study of robots of this type found that the distribution of the number of programs being run is summarised below. Number of programs | 1 | 2 | 3 | 4 Probability 0.5 0.25 0.15 0.1 (a) Determine the expected number of programs being run simultaneously on a randomly selected...
Most questions answered within 3 hours.
-
Calculate the pH of each of the following solutions.
0.50 M HBr
3.1×10−4 M KOH
4.2×10−5...
asked 57 minutes ago -
For the year ended December 31, Depot Max’s cost of merchandise
sold was $85,600. Inventory at the...
asked 56 minutes ago -
Week 10 - Professional Memo Assignment
Professional Memo Assignment
Your mission for this week, should you...
asked 1 hour ago -
Write a Python program that stores the data for each
player on the team, and it...
asked 1 hour ago -
In
the last 3 months, mike never knows when he is going to get his
allowance...
asked 1 hour ago -
Is Ca(OH)2 a Bronsted base, Lewis base, or both? Why?
asked 1 hour ago -
1A- Why don’t voters complain about U.S. tariffs on imported
sugar?
Because sugar is only a...
asked 1 hour ago -
Cash Payback Period
Primera Banco is evaluating two capital investment proposals for
a drive-up ATM kiosk,...
asked 1 hour ago -
Create a button in Swift (Xcode) that will create a charge,
create a charge using Stripe's...
asked 1 hour ago -
The reaction rate of CO and NO2 in the reaction
CO(g) + NO2(g) → CO2(g) +...
asked 1 hour ago -
Imagine that a chemist puts 6.40 mol each of
C3H8 and O2 in a 1.00-L container...
asked 1 hour ago -
How much money should be invested today in order to have $8340
at the end of...
asked 1 hour ago