I was wondering if grep, sed, and awk were viable tools for finding data in very large files.Lets say I have a 1TB file. If i wanted to process the text in that file, what would the time frame look like if i used the individual commands grep, sed, and awk, as well as mixing them together.Obviously a specific answer is not possible since the results will vary based on hardware specs, but if i could get a general estimation that would be helpful. 
How well does grep/sed/awk perform on very large files?
text processing;sed;awk;grep;performance
Generally I would say grep is the fastest one, sed is the slowest. Of course this depends on what are you doing exactly. I find awk much faster than sed.You can speed up grep if you don't need real regular expressions but only simple fixed strings (option -F).If you want to use grep, sed, awk together in pipes, then I would place the grep command first if possible.For example this:grep -F foo file | sed -n 's/foo/bar/p'is usually faster than this:sed -n 's/foo/bar/p' fileAlthough the grep in the first line seems unnecessary.BTW you may speed up these commands using LC_ALL=C if you are dealing with simple ASCII text files.Note all my experience is based on the gnu commands. You may also try different implementations and compare the speed.