Mapreduce style processing

parallel -j 50 ssh {} "ls" ::: host1 host2 hostn | sort | uniq -c
parallel can be installed on your central node and can be used to run a command multiple times. In this example, multiple ssh connections are used to run commands. (-j is the number of jobs to run at the same time). The result can then be piped to commands to perform the "reduce" stage. (sort then uniq in this example). This example assumes "keyless ssh login" has been set up between the central node and all machines in the cluster. bashreduce may also do what you want.
Sample Output
 1 Desktop
 1 documents
 2 downloads
 1 Dropbox

1
By: macoda
2013-04-12 11:56:41

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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