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http://stackoverflow.com/questions/2822005/java-difference-between-printstream-and-printwriter http://stackoverflow.com/questions/11372546/printstream-vs-printwriter
引用 a is an integer, n is a positive integer. C/C++ ===== quotient is rounded towards zero. a mod n = a - n (a/n) Python ====== Same as defined by CRLS.
For the following C++ code:   class person { public: person() {} person(const person& rhs) {} }; void func(person p) { } int main(int argc, const char *argv[]) { person yao; func(yao); return 0; }   Run "g++ -S" produces (some .cfi directives removed) ...
In a synchronous system, there are bounds on: - Time of computation - Time of message deliver   An asynchronous system is one that is not synchronous.      
Standby configurationsStandby configurations are the traditional redundant hardware configurations where one or more standby nodes stand idle, waiting for a server node to leave the cluster. Takeover configurationsIn the takeover configurations, all cluster nodes do useful work, processing part o ...
Section Visibility in http://gee.cs.oswego.edu/dl/cpj/jmm.html answesr this question.
Full Duplex: http://www.intel.com/support/express/switches/sb/CS-014409.htm
One disk drive has only one actuator arm. Every plate has 2 surfaces to store data. Throughput: 100MB/s Seek time: 10msec (100 seeks/s)
CLRS ----- 1) full binary tree: an ordered tree in which each internal node has degree 2 2) A complete k-ary tree: k-ary tree in which all leaves have the same depth and all internal nodes have degree k 严版数据结构 ---------- 1)满二叉树:深度为k且有2^k-1个结点的二叉树 2)完全二叉数:深度为k的,有n个结点的二叉树,当且仅当其每一个结点都与 ...
https://github.com/yaojingguo/data-mining/tree/master/PageRank
Lamport 1979 paper is often cited when talking about sequential consistency [1]. But the paper context is outdated. Robert Morris gives the following requirements which are together equivalent to IR1 and IR2 [2]: IR1: Every processor issues memory requests in the order specified by its progra ...
This problem is inspired by the discussion about ordering specification, BSort in the paper "Aurora: a new model and architecture for data stream management" Problem: There is an array A whose size is n. there is a ascending sorting with some disorder in A. The disorder is speci ...
Oracle uses STEAL NO-FORCE logging. The following content is just my conjecture which is not proved.    A log record has 2 parts: undo and redo. For Oracle, undo is treated differently. Undo data is written to pages, which in in turn triggers redo log writing. The following transaction update acc ...

Secondary Sort in Hadoop

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  • java
I write this stuff since it confused me a lot. First, the input Iterable values for reduce method is not sorted in any order. It is mentioned on Page 277 in Hadoop: The Definitive Guide, Third Edition. Job has three methods related to second sort:   1) setPartitionerClass   2) setSortComparatorC ...
1) Have a precise understanding of the key points. 2) Try to recite the main idea. 3) Make simple mental experiments. 4) Read other referenced papers and search google. 5) If too hard, stop. Do it again after skill grows. 6) Sometimes even the classic papers have minor errors, be prepared for ...
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