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Functions

grep (or anything else) many files with multiprocessor power

Terminal - grep (or anything else) many files with multiprocessor power
find . -type f | parallel -j+0 grep -i foobar
2010-01-30 02:08:46
Functions: find grep
3
grep (or anything else) many files with multiprocessor power

Parallel does not suffer from the risk of mixing of output that xargs suffers from. -j+0 will run as many jobs in parallel as you have cores.

With parallel you only need -0 (and -print0) if your filenames contain a '\n'.

Parallel is from https://savannah.nongnu.org/projects/parallel/

Alternatives

There are 7 alternatives - vote for the best!

Terminal - Alternatives
find . -type f -print0 | xargs -0 -P 4 -n 40 grep -i foobar
2009-08-05 23:18:44
User: ketil
Functions: find grep xargs
4

xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

Know a better way?

If you can do better, submit your command here.

What others think

Have you done some tests to estimate the gain ?

I haven't a multiprocessor computer but I not totally convinced.

I think find command is more limited by disk rate than by cpu, but I could be wrong.

Comment by Kysic 251 weeks and 4 days ago

It is very dependent on file system whether it is faster. But if the files are cached (e.g. if you just searched for another string), then it is definitely faster.

Comment by unixmonkey10455 226 weeks and 1 day ago

Your point of view

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