Is it possible that sort and shuffle phase in mapreduce can shuffle the already sorted input?
Let's say input to the mapper are already sorted by both key and value.
Key Value
A 1
A 2
B 1
B 3
B 5
It is also written to the system as the input to the reducer. Is it possible after sort and shuffle phase, this sorted order of key and value might get unsorted ?
hadoop mapreduce
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
add a comment |
Let's say input to the mapper are already sorted by both key and value.
Key Value
A 1
A 2
B 1
B 3
B 5
It is also written to the system as the input to the reducer. Is it possible after sort and shuffle phase, this sorted order of key and value might get unsorted ?
hadoop mapreduce
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
add a comment |
Let's say input to the mapper are already sorted by both key and value.
Key Value
A 1
A 2
B 1
B 3
B 5
It is also written to the system as the input to the reducer. Is it possible after sort and shuffle phase, this sorted order of key and value might get unsorted ?
hadoop mapreduce
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
Let's say input to the mapper are already sorted by both key and value.
Key Value
A 1
A 2
B 1
B 3
B 5
It is also written to the system as the input to the reducer. Is it possible after sort and shuffle phase, this sorted order of key and value might get unsorted ?
hadoop mapreduce
hadoop mapreduce
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
asked Nov 26 '18 at 9:11
Harsh kumarHarsh kumar
3418
3418
add a comment |
add a comment |
0
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53477806%2fis-it-possible-that-sort-and-shuffle-phase-in-mapreduce-can-shuffle-the-already%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53477806%2fis-it-possible-that-sort-and-shuffle-phase-in-mapreduce-can-shuffle-the-already%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
