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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Load file into RAM (cache) for faster accessing for repeated usage

Terminal - Load file into RAM (cache) for faster accessing for repeated usage
cat <file> > /dev/null
2011-11-12 15:45:27
User: totti
Functions: cat
Load file into RAM (cache) for faster accessing for repeated usage

Best result when file size less than half of RAM size


There is 1 alternative - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

+1 This is a great trick. This works because most OS's these days use memory not used by applications to cache file contents. When a file is read (here using the cat program) its contents are put into the page cache and subsequent accesses to that file don't have to touch disk... For more read this great blog post: http://duartes.org/gustavo/blog/post/page-cache-the-affair-between-memory-and-files

Comment by bwoodacre 293 weeks and 2 days ago

I don't think this will help much. The file will be cached during the first "real" access anyway. You would enter this command only if you have idle time now and already know that you will need a certain file later. But if you have idle, why not just begin the task?

On the other hand, projects like readahead https://fedorahosted.org/readahead/ try to speed up the boot process by preloading files that will be needed during boot.

Comment by hfs 293 weeks ago


1. The system (HDD) is not idle and i want to copy from an low speed device like CD,pen drive etc to the HDD.

2. I want to edit a big file and save it to the same DISK. (Or just backup it)

Comment by totti 292 weeks and 2 days ago

Your point of view

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