You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-issues@hadoop.apache.org by "Kazuho Fujii (JIRA)" <ji...@apache.org> on 2016/02/21 09:59:18 UTC

[jira] [Updated] (HADOOP-12830) Bash environment for quick command operations

     [ https://issues.apache.org/jira/browse/HADOOP-12830?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Kazuho Fujii updated HADOOP-12830:
----------------------------------
    Attachment: HADOOP-12830.001.path

Hi,

I attached a prototype.

Note that it has some issues:

 - stdin of hadoop command does not work
 - no test code

I tested this on Ubuntu 14.04. By using a Linux' own command (flock), it would not work on Mac.

I built this for using by myself, but I want to hear whether other users want it. As HADOOP-6541 remains opening, I'm not sure this feature should be included Hadoop's code base or not.

If interested, could you give me a comment.

Regard,


> 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
>         Attachments: HADOOP-12830.001.path
>
>
> 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)