defragment files

find ~ -maxdepth 20 -type f -size -16M -print > t; for ((i=$(wc -l < t); i>0; i--)) do a=$(sed -n ${i}p < t); mv "$a" /dev/shm/d; mv /dev/shm/d "$a"; echo $i; done; echo DONE; rm t
Thanks to flatcap for optimizing this command. This command takes advantage of the ext4 filesystem's resistance to fragmentation. By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it ) My command only effects the home directory and only those files with your R/W (read / write ) permissions. There are two issues with this command: 1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O 2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory The benefits i managed to work into the command: 1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long 2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c ) 3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage bottom line: 1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer 2. it's my first commandlinefu command
Sample Output
11
10
9
8
7
6
5
4
3
2
1
0
DONE

2
By: LinuxMan
2010-07-07 04:29:22

What Others Think

I'm impressed, but why is the chmod there at all? Why not keep the file's original permissions?
kaedenn · 714 weeks and 5 days ago
I'm intrigued to know what you're doing that's SO time dependent. ext4 is pretty fast, so unless you have millions of files, or you read these files millions of times, I doubt you'd ever notice the problem of fragmentation. As for the script... First get rid of sudo. You're performing this operation in your own home directory. Next, if you mv a file onto /dev/shm (another filesystem) and you mv it back you will get a new file. By mv'ing the file, you don't need to worry about chmod (or rm). Big security note, though. If someone else has created a file in /dev/shm called 'd', your script will replace all your files with it. Next, I've used wc (word count) which is faster than grep. I only use it once, too, to initialise a for loop. Then, instead of sed reading/altering/writing the file list every loop, I get it to give me the n'th line. Finally, I added "rm t" to clean up the temporary file. For speed, you could put the file in /dev/shm too :-) Here's my updated version: find ~ -maxdepth 20 -type f -size -16M -print > t; for ((i=$(wc -l < t); i>0; i--)) do a=$(sed -n ${i}p < t); mv "$a" /dev/shm/d; mv /dev/shm/d "$a"; echo $i; done; echo DONE; rm t 74 fewer chars. List of commands: find, wc, sed, mv, rm, echo
flatcap · 714 weeks and 5 days ago
Thank you flatcap, you've managed to squeeze my command into an even smaller space and remove the junk from my command ( left over from my big 2kb command, i was so concerned with reducing the size of to under 255 characters, i failed to realize that some code from the original script wasn't necessary anymore ). after testing your script, i would like to know if i can replace my command with yours. @kaedenn the chmod was left over from my original script that used "dd" and attempted to work on files aoutside of the home directory
LinuxMan · 714 weeks and 5 days ago
No problem, I enjoyed the challenge :-) I didn't do much testing, but I'm /fairly/ certain it'll do the same as your script. Be careful before using it on your home directory.
flatcap · 714 weeks and 5 days ago
You could use mktemp to bypass the potential /dev/shm/d file issue. The temp file will be created when the var is set. d=$(mktemp --tmpdir=/dev/shm); find ~ -maxdepth 20 -type f -size -16M -print > t; for ((i=$(wc -l < t); i>0; i--)) do a=$(sed -n ${i}p < t); mv "$a" /dev/shm/$d; mv /dev/shm/$d "$a"; echo $i; done; echo DONE; rm t; rm $d
Vilemirth · 540 weeks and 5 days ago
Sorry. Screwed that up. You don't need the path for $d, as it's already there. d=$(mktemp --tmpdir=/dev/shm); find ~ -maxdepth 20 -type f -size -16M -print > t; for ((i=$(wc -l < t); i>0; i--)) do a=$(sed -n ${i}p < t); mv "$a" "$d"; mv "$d" "$a"; echo $i; done; echo DONE; rm t; rm $d
Vilemirth · 540 weeks and 5 days ago
Pug Puppies for Sale Near Me pugs puppies for sale teacup pugs for sale pug puppies for sale by owner pug puppies ohio PUG PUPPY FOR SALE NEAR ME PUG PUPPIES FOR SALE pug puppies for sale in kentucky Pug Puppies for Sale Under $500 Near Me pug puppies for sale in texas pug puppies for sale $200 pugs for sale near me under $500 pugs for sale under $400 near me pugs for sale near me puppies for sale near me under $500 pug puppies for sale under $1,000 near me pug for sale pug puppies for sale under $300 Brindle Pug Pitbull Pug Mix Pugs for sale cheap Cheap pug affordable pug puppies for sale near me black pugs for sale near me White Pugs for sale pug dog for sale free pug puppies pug puppies for sale in my area mn pug breeders pug puppies indiana pugs for sale michigan PUG PUPPY ADOPTION Pug puppies for sale Pug puppies for sale near me Pug puppies near me Pug Puppies for Sale Under $500 Near Me Cute Pug Puppies Black pug puppies Black pug puppies for sale pug puppies for adoption black pug puppies for sale near me chihuahua pug mix puppies how much is a pug puppy teacup pug puppies baby pug puppies pictures of pug puppies pug puppies for sale in Ohio pug puppies price pug mix puppies teacup pug puppies for sale best food for pug puppy newborn pug puppies pug puppies craigslist pug puppies for sale craigslist adorable pug puppies how much does a pug puppy cost Pitbull pug mix puppies pug pit mix puppy pug puppies for sale $200 pug puppies for sale in NJ Pug puppies for sale in Wisconsin pug puppy cost pug puppy food royal canin pug puppy royal canin pug puppy food fawn pug puppy pug puppies for sale florida pug puppies for sale in Indiana pug puppies for sale in KY pug puppies for sale in NC pug dog puppy AKC Registered Pug Puppies For sale cheap pug puppies for sale near me cheap pug puppies for sale in California cheap pug puppies for sale in nj Black Pug Puppies for sale pugs puppies for sale pug puppies indiana Amazing! This blog looks just like my old one! It's on a completely different subject but it has pretty much the same layout and design. Wonderful choice of colors!
rahimhh21 · 80 weeks and 6 days ago
Pug Puppies for Sale Near Me pugs puppies for sale teacup pugs for sale pug puppies for sale by owner pug puppies ohio PUG PUPPY FOR SALE NEAR ME PUG PUPPIES FOR SALE pug puppies for sale in kentucky Pug Puppies for Sale Under $500 Near Me pug puppies for sale in texas pug puppies for sale $200 pugs for sale near me under $500 pugs for sale under $400 near me pugs for sale near me puppies for sale near me under $500 pug puppies for sale under $1,000 near me pug for sale pug puppies for sale under $300 Brindle Pug Pitbull Pug Mix Pugs for sale cheap Cheap pug affordable pug puppies for sale near me black pugs for sale near me White Pugs for sale pug dog for sale free pug puppies pug puppies for sale in my area mn pug breeders pug puppies indiana pugs for sale michigan PUG PUPPY ADOPTION Pug puppies for sale Pug puppies for sale near me Pug puppies near me Pug Puppies for Sale Under $500 Near Me USA USA USA USA USA USA Cute Pug Puppies Black pug puppies Black pug puppies for sale pug puppies for adoption black pug puppies for sale near me chihuahua pug mix puppies how much is a pug puppy teacup pug puppies baby pug puppies baby pug puppies for sale pictures of pug puppies pug puppies for sale in Ohio pug puppies price pug mix puppies teacup pug puppies for sale best food for pug puppy newborn pug puppies pug puppies craigslist pug puppies for sale craigslist adorable pug puppies how much does a pug puppy cost Pitbull pug mix puppies pug pit mix puppy pug puppies for sale $200 pug puppies for sale in NJ Pug puppies for sale in Wisconsin pug puppy cost pug puppy food royal canin pug puppy royal canin pug puppy food fawn pug puppy pug puppies for sale florida pug puppies for sale in Indiana pug puppies for sale in KY pug puppies for sale in NC pug dog puppy AKC Registered Pug Puppies For sale cheap pug puppies for sale near me cheap pug puppies for sale in California cheap pug puppies for sale in nj Black Pug Puppies for sale pugs puppies for sale
Perfecthomepugs · 72 weeks ago
Perfect House Of Pugs acquired a passion for animals, and the Pug puppy in particular, at a young age since I grew up in a house with lots of dogs. It was a natural ability to know how to grow, nurture, and care for animals. I knew what the future held when I met my wife, who essentially had the same enthusiasm as I have. Being a breeder is more of a passion for me than a profession since I get to witness people's faces light up when they successfully adopt a pug puppy from our facility. It is not possible to find happiness in anything else. PLEASE VISIT OUR WEBSITE LINK BELLOW FOR MORE INFORMATION ABOUT PUG PUPPIES. PUG PUPPY ADOPTION Pug puppies for sale PUG PUPPIES FOR SALE NEAR ME PUG PUPPIES NEAR ME PUG PUPPIES FOR SALE UNDER 500 NEAR ME CUTE PUG PUPPIES BLACK PUG PUPPIES BLACK PUG PUPPIES FOR SALE PUG PUPPIES FOR ADOPTION BLACK PUG PUPPIES FOR SALE NEAR ME CHIHUAHUA PUG MIX PUPPIES TEACUP PUG PUPPIES HOW MUCH IS A PUG PUPPY BABY PUG PUPPIES PICTURES OF PUG PUPPIES PUG PUPPIES FOR SALE IN OHIO PUG PUPPIES FOR SALE IN PA PUG PUPPIES PRICE PUG MIX PUPPIES TEACUP PUG PUPPIES FOR SALE BABY PUG PUPPIES FOR SALE BEST FOOD FOR PUG PUPPY NEWBORN PUG PUPPIES PUG PUPPIES CRAIGSLIST PUG PUPPIES FOR SALE CRAIGSLIST WHITE PUG PUPPIES PUG PUPPIES FOR SALE IN MICHIGAN PUG PUPPIES FOR SALE UNDER 500 ADORABLE PUG PUPPIES BRINDLE PUG PUPPY HOW MUCH DOES A PUG PUPPY COST PITBULL PUG MIX PUPPIES PUGS FOR SALE NEAR ME PUG PUPPIES FOR SALE 200 PUG PUPPIES FOR SALE IN NJ PUG PUPPIES FOR SALE IN WISCONSIN PUG PUPPIES MICHIGAN PUG PUPPY COST MERLE PUG PUPPY FOR ADOPTION BEST PUG PUPPY FOOD ROYAL CANIN PUG PUPPY FOOD FAWN PUG PUPPY PUG PUPPIES FOR SALE FLORIDA PUG PUPPIES FOR SALE IN INDIANA PUG PUPPIES FOR SALE IN KY PUG PUPPIES FOR SALE IN NC PUG PUPPIES FOR SALE IN TEXAS PUG PUPPIES FOR SALE MN PUG DOG PUPPY AKC REGISTERED PUG PUPPIES FOR SALE PUG ALL BLACK CHEAP PUG PUPPIES FOR SALE NEAR ME PUGS PUPPIES FOR SALE CHEAP PUG PUPPIES FOR SALE IN CALIFORNIA MINIATURE PUG PUPPIES FOR SALE NEAR ME MINIATURE PUG PUPPIES FOR SALE CHEAP PUG PUPPIES FOR SALE IN NJ KNOWN FACTS ABOUT PUG PUPPIES ADOPT PUG PUPPIS RESCUE A PUG PUPPY PERFECT HOUSE OF PUGS PUG PUPPIES INSTAGRAM PINTEREST QUORA Google Page USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA USA
pugpuppies95 · 34 weeks and 1 day 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?

You must be signed in to comment.

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands



Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: