Difference between revisions of "MapReduce Frameworks Lab"

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[[Bottleneck_MapReduce_Framework_Assignment|Bottleneck MapReduce Framework]]
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[[Matrix_MapReduce_Framework_Assignment|Matrix MapReduce Framework]]
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<!--
 
credit for this assignment: Finn Voichick and Dennis Cosgrove
 
credit for this assignment: Finn Voichick and Dennis Cosgrove
 
=Motivation=
 
=Motivation=
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=Code To Use=
 
=Code To Use=
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To allow our frameworks to work well with JDK8 Streams, we employ a couple of standard interfaces over creating out own custom ones.
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To allow our frameworks to work well with JDK8 Streams, we employ a couple of standard interfaces over creating our own custom ones.
  
 
==BiConsumer==
 
==BiConsumer==
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* [[#Optional_Warm_Up]]
 
* [[#Optional_Warm_Up]]
 
* [[#Bottlenecked_MapReduce_Framework]]
 
* [[#Bottlenecked_MapReduce_Framework]]
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<!--
 
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* Wait For Thursday's Class Session (If Applicable)
 
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-->
 
 
* [[Cholera_MapReduce_Application]]
 
* [[Cholera_MapReduce_Application]]
 
* [[#Matrix_MapReduce_Framework]]
 
* [[#Matrix_MapReduce_Framework]]
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===Reducer===
 
===Reducer===
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====reduceCreateList (Provided)====
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====createMutableContainer (Provided)====
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  <nowiki> static List<Integer> reduceCreateList() {
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  <nowiki> static List<Integer> createMutableContainer() {
 
return collector.supplier().get();
 
return collector.supplier().get();
 
}</nowiki>
 
}</nowiki>
  
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====reduceAccumulate (Provided)====
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====accumulate (Provided)====
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  <nowiki> static void reduceAccumulate(List<Integer> list, int v) {
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  <nowiki> static void accumulate(List<Integer> list, int v) {
 
collector.accumulator().accept(list, v);
 
collector.accumulator().accept(list, v);
 
}</nowiki>
 
}</nowiki>
  
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====reduceCombine (Provided)====
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====combine (Provided)====
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  <nowiki> static List<Integer> reduceCombine(List<Integer> a, List<Integer> b) {
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  <nowiki> static List<Integer> combine(List<Integer> a, List<Integer> b) {
 
return collector.combiner().apply(a, b);
 
return collector.combiner().apply(a, b);
 
}</nowiki>
 
}</nowiki>
  
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====reduceFinish (Provided)====
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====reduce (Provided)====
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  <nowiki> static int reduceFinish(List<Integer> list) {
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  <nowiki> static int reduce(List<Integer> list) {
 
return collector.finisher().apply(list);
 
return collector.finisher().apply(list);
 
}</nowiki>
 
}</nowiki>
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===Framework===
 
===Framework===
 
====mapAll====
 
====mapAll====
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mapAll can be performed in parallel.  A task should be created for each item in the input array.  Each task should accept the emitted (key, value) pairs and store them in its own List to avoid data races.  These lists make up the array which is returned (one list for each item in the input array).
 +
 
<youtube>-4prus5cNFo</youtube>
 
<youtube>-4prus5cNFo</youtube>
  
 
{{Parallel|List<KeyValuePair<String, Integer>>[] mapAll(TextSection[] input)}}
 
{{Parallel|List<KeyValuePair<String, Integer>>[] mapAll(TextSection[] input)}}
  
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{{Warning| When first created arrays of Objects are filled with null.  You will need to assigned each array index to a new List before you start the process of adding key-value pairs}}
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{{Warning| When first created arrays of Objects are filled with null.  You will need to assign each array index to a new List before you start the process of adding key-value pairs}}
  
 
{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
 
{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
  
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You are encouraged to utilize the provided [[#map_.28Provided.29|map]] method.
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{{Tip|You are encouraged to utilize the provided [[#map_.28Provided.29|map]] method.}}
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 +
[[File:Map_all.svg]]
  
 
====accumulateAll====
 
====accumulateAll====
 
{{Sequential|static Map<String, List<Integer>> accumulateAll(List<KeyValuePair<String, Integer>>[] mapAllResults)}}
 
{{Sequential|static Map<String, List<Integer>> accumulateAll(List<KeyValuePair<String, Integer>>[] mapAllResults)}}
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{{Tip|You are encouraged to utilize the provided [[#createMutableContainer_.28Provided.29|createMutableContainer]] and [[#accumulate_.28Provided.29|accumulate]] methods.}}
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[[File:Accumulate_all.svg]]
  
 
====finishAll====
 
====finishAll====
 
{{Parallel|static Map<String, Integer> finishAll(Map<String, List<Integer>> accumulateAllResult)}}
 
{{Parallel|static Map<String, Integer> finishAll(Map<String, List<Integer>> accumulateAllResult)}}
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 +
{{Tip|You are encouraged to utilize the provided [[#reduce_.28Provided.29|reduce]] method.}}
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 +
[[File:Finish_all.svg]]
  
 
===Testing Your Solution===
 
===Testing Your Solution===
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{{CodeToImplement|MutualFriendsConcreteStaticMapReduce|map<br>reduceCreateList<br>reduceAccumulate<br>reduceCombine<br>reduceFinish<br>mapAll<br>accumulateAll<br>finishAll|mapreduce.framework.warmup.friends}}
 
{{CodeToImplement|MutualFriendsConcreteStaticMapReduce|map<br>reduceCreateList<br>reduceAccumulate<br>reduceCombine<br>reduceFinish<br>mapAll<br>accumulateAll<br>finishAll|mapreduce.framework.warmup.friends}}
 
===Mapper===
 
===Mapper===
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====map====
 
{{Sequential|static void map(Account account, BiConsumer<OrderedPair<AccountId>, Set<AccountId>> keyValuePairConsumer)}}
 
{{Sequential|static void map(Account account, BiConsumer<OrderedPair<AccountId>, Set<AccountId>> keyValuePairConsumer)}}
  
 
===Reducer===
 
===Reducer===
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{{Sequential|static List<Set<AccountId>> reduceCreateList()}}
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====createMutableContainer====
 +
{{Sequential|static List<Set<AccountId>> createMutableContainer()}}
  
−
{{Sequential|static void reduceAccumulate(List<Set<AccountId>> list, Set<AccountId> v)}}
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====accumulate====
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{{Sequential|static void accumulate(List<Set<AccountId>> list, Set<AccountId> v)}}
  
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{{Sequential|static void reduceCombine(List<Set<AccountId>> a, List<Set<AccountId>> b)}}
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====combine====
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{{Sequential|static void combine(List<Set<AccountId>> a, List<Set<AccountId>> b)}}
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====reduce====
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{{Sequential|static AccountIdMutableContainer reduce(List<Set<AccountId>> list)}}
  
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{{Sequential|static MutualFriendIds reduceFinish(List<Set<AccountId>> list)}}
 
 
===Framework===
 
===Framework===
 
====mapAll====
 
====mapAll====
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{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
 
{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
 +
 +
{{Tip|You are encouraged to utilize the [[#map|map]] method you implemented.}}
 
====accumulateAll====
 
====accumulateAll====
 
{{Sequential|static Map<OrderedPair<AccountId>, List<Set<AccountId>>> accumulateAll(List<KeyValuePair<OrderedPair<AccountId>, Set<AccountId>>>[] mapAllResults)}}
 
{{Sequential|static Map<OrderedPair<AccountId>, List<Set<AccountId>>> accumulateAll(List<KeyValuePair<OrderedPair<AccountId>, Set<AccountId>>>[] mapAllResults)}}
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 +
{{Tip|You are encouraged to utilize the [[#reduceCreateList|reduceCreateList]] and [[#reduceAccumulate|reduceAccumulate]] methods you implemented.}}
  
 
====finishAll====
 
====finishAll====
 
{{Parallel|static Map<OrderedPair<AccountId>, MutualFriendIds> finishAll(Map<OrderedPair<AccountId>, List<Set<AccountId>>> accumulateAllResult)}}
 
{{Parallel|static Map<OrderedPair<AccountId>, MutualFriendIds> finishAll(Map<OrderedPair<AccountId>, List<Set<AccountId>>> accumulateAllResult)}}
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{{Tip|You are encouraged to utilize the [[#reduceFinish|reduceFinish]] method you implemented.}}
  
 
===Testing Your Solution===
 
===Testing Your Solution===
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{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
 
{{Warning| Reminder: our course libraries consistently specify max to be exclusive.  This includes the parallel forall loop.}}
  
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With this method, you will map all of the elements of an array of data into a new array of equivalent size consisting of a list of key value pairs. In order to do this, you must define the map() method for the mapper by specifying that it should add a new key value pair to a previously empty list. This list should then be added to the array of lists you previously defined, therefore completing the mapping stage of MapReduce. This should all be done in parallel.
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With this method, you will map all of the elements of an array of data into a new array of equivalent size consisting of Lists of key value pairs. We will leverage the Mapper which is a field/instance variable on this BottleneckedFramework instance.  When invoking the mapper's map method with an element of the input array and a BiConsumer which will  accept each key and value passed to it, adding a KeyValuePair to its List. This list should then be added to the array of lists you previously defined, therefore completing the mapping stage of MapReduce. This should all be done in parallel.
  
 
Hint: you should create an array of lists equivalent in size to the original array. Each list will contain all of the emitted (key,value) pairs for its item.
 
Hint: you should create an array of lists equivalent in size to the original array. Each list will contain all of the emitted (key,value) pairs for its item.
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In this method, you will take in the array of lists you previously created and accumulate the key value pairs in the lists into a newly defined map.  To help deal with this issue, you must make use of the Collector provided to you. More specifically, access the accumulator in the collector by calling the <code>accumulator()</code> method and accept the key/value pair when you add it to the map. You probably noticed that the method must return a map of <K, A>, which differs from the <K, V> generics fed into the method. The framework is designed this way as the data originally fed into the mapping stage can be collected into a mutable container before reaching the finish/reduce stage. In order to access the correct value for the map if the key has no associated value yet, use the supplier associated with the Collector with the <code>supplier()</code> method.
 
In this method, you will take in the array of lists you previously created and accumulate the key value pairs in the lists into a newly defined map.  To help deal with this issue, you must make use of the Collector provided to you. More specifically, access the accumulator in the collector by calling the <code>accumulator()</code> method and accept the key/value pair when you add it to the map. You probably noticed that the method must return a map of <K, A>, which differs from the <K, V> generics fed into the method. The framework is designed this way as the data originally fed into the mapping stage can be collected into a mutable container before reaching the finish/reduce stage. In order to access the correct value for the map if the key has no associated value yet, use the supplier associated with the Collector with the <code>supplier()</code> method.
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−
<!--
 
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Hint: Look into the <code>compute()</code> method for maps.
 
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-->
 
  
 
[[File:Bottlenecked accumulate all.png|400px]] [https://docs.google.com/presentation/d/1Gtpj6_5_8imUMccpwxmfrOxKSED791OKl4lZR6G2Bm4/pub?start=false&loop=false&delayms=3000&slide=id.g7ea283730e_0_165 slide]
 
[[File:Bottlenecked accumulate all.png|400px]] [https://docs.google.com/presentation/d/1Gtpj6_5_8imUMccpwxmfrOxKSED791OKl4lZR6G2Bm4/pub?start=false&loop=false&delayms=3000&slide=id.g7ea283730e_0_165 slide]
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[[File:Matrix map accumulate art.png|400px]] [https://docs.google.com/presentation/d/1bSLKsI5u2e_tFc0d-RSb0BIDwA-kD75U6yXfxvpMf6Y/pub?start=false&loop=false&delayms=3000&slide=id.g7ebdc248f6_0_388 slide]
 
[[File:Matrix map accumulate art.png|400px]] [https://docs.google.com/presentation/d/1bSLKsI5u2e_tFc0d-RSb0BIDwA-kD75U6yXfxvpMf6Y/pub?start=false&loop=false&delayms=3000&slide=id.g7ebdc248f6_0_388 slide]
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<!-- [[File:Matrix map accumulate death.png]]-->
 
  
 
===combineAndFinishAll===
 
===combineAndFinishAll===
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* Correct mapAndAccumulateAll (30)
 
* Correct mapAndAccumulateAll (30)
 
* Correct combineAndFinishAll (30)
 
* Correct combineAndFinishAll (30)
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-->

Latest revision as of 08:23, 3 March 2022

Bottleneck MapReduce Framework

Matrix MapReduce Framework


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