Kazuho Fujii created HADOOP-12830: ------------------------------------- Summary: Bash environment for quick command operations Key: HADOOP-12830 URL: https://issues.apache.org/jira/browse/HADOOP-12830 Project: Hadoop Common Issue Type: New Feature Components: bin Reporter: Kazuho Fujii Assignee: Kazuho Fujii
Hadoop file system shell commands are slow. This issue is about building a shell environment for quick command operations. Previously an interactive shell is tried to build in HADOOP-6541. But, it seems to be poor because users are used to powerful shells like bash. This issue is not about creating a new shell, but just opening a new bash process. Therefore, user can operate commands as before. {code} fjk@x240:~/hadoop-2.7.2$ ./bin/hadoop shell fjk@x240 hadoop> hadoop fs -ls / Found 2 items -rw-r--r-- 3 fjk supergroup 0 2016-02-21 00:26 /file1 -rw-r--r-- 3 fjk supergroup 0 2016-02-21 00:26 /file2 {code} The shell has a mini daemon process that is living until the shell is closed. The hadoop fs command delegates the operation to the daemon. They communicate with named pipes. The daemon conducts the operation and returns the result to the command. In this shell the hadoop fs commands operation becomes quick. In a local environment, "hadoop fs -ls" command is about 100 times faster than the normal command. {code} fjk@x240 hadoop> time hadoop fs -ls hdfs://localhost:8020/ > /dev/null real 0m0.021s user 0m0.003s sys 0m0.011s {code} Using bash's function, commands and file names are automatically completed. {code} fjk@x240 hadoop> hadoop fs -ch<TAB><TAB> -checksum -chgrp -chmod -chown fjk@x240 hadoop> hadoop fs -ls /file<TAB><TAB> /file1 /file2 /file3 {code} Additionally, we can make equivalents with bash build-in commands, e.g., cd, umask. In this shell, they can work because the daemon remembers the state. -- This message was sent by Atlassian JIRA (v6.3.4#6332)