java - about hadoop filesystem transferFromLocalFile -

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java - about hadoop filesystem transferFromLocalFile -

i writing code transfer files hadoop hdfs parallel. have many threads calling filesystem.copyfromlocalfile.

i think cost of opening filesystem not small, have 1 filesystem opened in project. though there might a problem when many threads calling @ same time. far, works fine no problem.

could please give me info re-create method? give thanks much& have great weekend.

i see next design points consider: a) bottleneck of process? think in 2-3 parallel re-create operations local disk or 1gb ethernet became bottleneck. can in form of multithreaded application or can run few processes. in case not think need high level of parallelism. b) error handling. failure of 1 thread should not stop whole process, and, in same time file should not lost. doing in such cases agree in worst case file can copied twice. if ok - scheme can work in simple "copy delete" scenario. c) if re-create 1 of cluster nodes - hdfs became unbalanced, since 1 replica stored on host copy. need balance constantly.

java hadoop hdfs

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