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

cat <file> > /dev/null
Best result when file size less than half of RAM size

By: totti
2011-11-12 15:45:27

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
bwoodacre · 518 weeks and 3 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.
hfs · 518 weeks and 1 day ago
Suppose 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)
totti · 517 weeks and 3 days ago

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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