6

How to find the BlockName to DataNode mapping in Hadoop

 3 years ago
source link: https://www.codesd.com/item/how-to-find-the-blockname-to-datanode-mapping-in-hadoop.html
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.

How to find the BlockName to DataNode mapping in Hadoop

advertisements

Is there a programatic interface to find out whether given a blockID it exists on which data node. I.e. ability to read fsImage and return this info.

One of the crude ways i know of is to look for a file with blockName in the dfs data dir. This is however an O(n) solution and i am pretty sure there would be an O(1) solution to this.

Related Articles

how to find the central element of the map ?? STL

Hi I am stuck in between the concept of Map in STL Library/C++. int arr[] = {10,15,14,13,17,15,16,12,18,10,29,24,35,36}; int n = sizeof arr / sizeof *arr; map<int, bool> bst; map<int, bool>::iterator it; vector<int> median_output; const

How to find the menu item (if any) that opens a given HMENU when it is enabled?

I'd like to implement a function with the prototype /* Locates the menu item of the application which caused the given menu 'mnu' to * show up. * @return true if the given menu 'mnu' was opened by another menu item, false * if not. */ bool getParentM

How to find the keys of the card that are not in the keys of another card?

I have declared two maps m1 and m2. Map m1's keys are in the keys of m2. But all the keys of m2 are not in the keys of m1. Can anyone help me how to find the uncommon keys in m2 compared to the keys of m1? Example m1 contains: 3=> 1 2 4 6=> 3 4 6 m2

How to find the longest common prefix of two strings in Scala?

How to find the longest common prefix of two strings in Scala? I probably can code an "imperative" solution (with an index i running over the strings while s(i) == t(i)) but I am looking for a "functional-style" solution (without updat

How to find the most frequent number in 1T numbers?

How to find the most frequent number(int type) in 1T (i.e. 10^12) numbers? My premises are: My memory is limited to 4G (i.e. 4·10^9) bytes. All the numbers are stored in a file as the input. The output is just one number. All numbers(int type) are st

How to find the median values ​​in a Hashtable in Java?

I have Hashtable<String, Integer> ht. How to find the values' (Integer) median in this hashtable efficiently?There is no meaningful ordering in a hash table: the whole point of a hash table is to scatter values uniformly in buckets, according to the

How to find the location using the MAC address of the phone?

How to find the current location based on the phone mac address or gps or tower locaiton by using the google map. Please let me know if have any html code sampleUse watch my location API and it will help to get the current location every sec. You jus

How to find the most common character in a large chain using java?

i'm working on an assignment that i have to find the most four frequent characters in a string. i write this so far. import java.util.Scanner; public class FindTheMostOccur { public static void main (String[] args) { String input; String example = "h

How to find the length of an array of std :: strings?

I have a few questions related to portions of my code. The first has to do with how I find the length of an array of arrays of strings. I'm using the following as a map for a Calculus tool I'm using. std::string dMap[][10] = {{"x", "1"

How to find the end address of a function in a C program?

Start address can be obtained from the function name, how to find the end address of a function? I have been asked this question in interview: Consider the function f() which i wrote has crossed the text section and started over writing the adjacent

How to find the number of factors of & ldquo; product of numbers & rdquo;

I m trying to find number of factors of product of big numbers. The problem statement is this : Suppose you are given N numbers(let say N = 10), each number <= 1000000. How to find the number of factors of the product of such numbers. Can someone ple

How to find the li index that does not have an identifier?

Hi I am creating tabs in JSP using twitter bootstrap. <ul> <li id="first"><a href="#datacollector" target="main"data-toggle="tab">General</a></li> <li><a href="#dataTab&qu

How to find the largest number in a string that contains not only numbers but words?

How to find the biggest number in a string that contains not just numbers but words? For example: String naa = "John 19, Reuben 21, sbu 6, Derick 33"; I need to be able to find the highest age no mater the names and ages entered.I'm not sure wha

How to find the number of unique names from the list of matched data with linked information?

I have got 'n' rows of data sets, each data set having two components separated by space. First is card number and second is name. A person is same, if he has same card number or the name. How to find the total number of unique person from the data s

report

Recommend

About Joyk


Aggregate valuable and interesting links.
Joyk means Joy of geeK