Commands using sync sorted by votes

Commands using sync (12)

sorted by

Clear filesystem memory cache

Found here: http://ubuntuforums.org/showthread.php?t=589975
This is sample output - yours may be different.
9

sync && echo 3 | sudo tee /proc/sys/vm/drop_caches

mariusbutuc · 2011-10-18 15:22:25 34
Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible. Show Sample Output
This is sample output - yours may be different.
```
1+0 records in
1+0 records out
268435456 bytes (268 MB) copied, 1.50648 seconds, 178 MB/s

real    0m7.119s
user    0m0.002s
sys     0m0.649s
```
2

time (dd if=/dev/zero of=blah.out bs=256M count=1 ; sync )

tkunz · 2009-07-14 20:19:23 7
clear the cache from memory
This is sample output - yours may be different.
2

sync; echo 3 > /proc/sys/vm/drop_caches

lunarblu · 2009-08-20 17:28:56 7
Get the list of local files that changed since their last upload in an S3 bucket

Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket. Show Sample Output
This is sample output - yours may be different.
```
/css/app_facebook.css
/css/cupertino/jquery-ui-1.7.2.custom.css
/css/fan_css.css
/css/main.css
```
2

changing_assets = `s3cmd sync --dry-run -P -M --exclude=*.php --delete-removed #{preprod_release_dir}/web/ #{s3_bucket} | grep -E 'delete:|upload:' | awk '{print $2}' | sed s_#{preprod_release_dir}/web__`

trivoallan · 2010-05-07 16:03:42 4
Testing reading speed with dd
This is sample output - yours may be different.
1

sync; time `dd if=/dev/cciss/c0d1p1 of=/dev/null bs=1M count=10240`

w00binda · 2009-11-19 10:34:13 4

Search vmware vmx files if Linux guests are set to sync time to host

besure to adjust your find to use to correct location of your VMX files. Show Sample Output

for x in `find /vmfs/volumes/ -name *vmx -exec grep -H linux.iso {} \; |cut -d : -f 1`; do echo $x; grep -i sync $x; done;

uid0 · 2009-10-30 16:19:16 3

Testing writing speed with dd
This is sample output - yours may be different.
0

sync; time `dd if=/dev/zero of=bigfile bs=1M count=2048 && sync`

w00binda · 2009-11-19 10:29:03 14
Clear Cached Memory on Ubuntu

"That's it. Not much to see here. The first command writes any cache data that hasn't been written to the disk out to the disk. The second command tells the kernel to drop what's cached. Not much to it. This invalidates the write cache as well as the read cache, which is why we have the sync command first. Supposedly, it is possible to have some cached write data never make it to disk, so use it with caution, and NEVER do it on a production server. You could ... but why take the risk? As long as you are running a post 2.6.16 kernel,..." Source: http://ubuntuforums.org/showpost.php?p=3621283&postcount=1
This is sample output - yours may be different.
0

sudo sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches

StephenJudge · 2012-03-17 08:27:58 15
Clean memory and SO cache
This is sample output - yours may be different.
0

sync ; /sbin/sysctl -w vm.drop_caches=3 ; sync ; sleep 2 ; /sbin/sysctl -w vm.drop_caches=0 ;/sbin/swapoff -a ; sleep 2 ;/sbin/swapon -a

szimbaro · 2013-02-27 12:39:20 5
Clear Cached Memory on Ubuntu

Clear Cached Memory on Ubuntu based distributions, and also display memory status. Please do not use this on a production machine unless you really really know what you are doing. Echo 3 is a kinder way of purging the memory, you can also use 'echo 2' or 'echo 1' if #1 You know what you are doing, and #2 refer to number 1 :-)
This is sample output - yours may be different.
0

sudo free && sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches

tg0000 · 2021-09-13 16:45:20 671
Flush memory cache
This is sample output - yours may be different.
-3

free && sync && echo 3 > /proc/sys/vm/drop_caches && free

ironmarc · 2016-11-02 08:51:01 23
clean up memory on linux (fedora)

It clears caches from memory. It works fine on CentOS and Fedora. It will show you how much memory you need, for real.
This is sample output - yours may be different.
-4

sync; echo 3 > /proc/sys/vm/drop_caches

renich · 2011-04-26 21:12:06 12

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

Check These Out

Substitute audio track of video file using mencoder

Creates a new video file with video stream copied from input file and a different audio stream

Recursive find and replace file extension / suffix (mass rename files)

Find recursively all files in ~/Notes with the extension '.md' and pipe that via xargs to rename command, which will replace every '.md' to '.txt' in this example (existing files will not be overwritten).

list the top 15 folders by decreasing size in MB

Get free RAM in %

Oneliner to run commands on multiple servers

Oneliner to run commands on multiple servers over ssh. - First parameter "$1" is the command you want to execute remotely. ( It can be multiple commands e.g. "hostname;uptime") - Second parameter "${@:2}" represents the remote host/s you want to run the command/s on.

Fast command-line directory browsing

After typing cd directory [enter] ls [enter] so many times, I figured I'd try to make it into a function. I was surprised how smoothly I was able to integrate it into my work on the command line. Just use cdls as you would cd. It will automatically list the directory contents after you cd into the directory. To make the command always available, add it to your .bashrc file. Not quite monumental, but still pretty convenient.

Copy the contents of one partition to another

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

list block devices

Shows all block devices in a tree with descruptions of what they are.

Job Control

You're running a script, command, whatever.. You don't expect it to take long, now 5pm has rolled around and you're ready to go home... Wait, it's still running... You forgot to nohup it before running it... Suspend it, send it to the background, then disown it... The ouput wont go anywhere, but at least the command will still run...

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:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands using sync

Commands using sync (12) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

Commands using sync (12)

sorted by