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Commands using sync from sorted by
Terminal - Commands using sync - 11 results
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
sudo sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches
2012-03-17 08:27:58
User: StephenJudge
Functions: echo sudo sync tee
Tags: memory cache
-2

"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

sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
sync; echo 3 > /proc/sys/vm/drop_caches
2011-04-26 21:12:06
User: renich
Functions: echo sync
-4

It clears caches from memory. It works fine on CentOS and Fedora. It will show you how much memory you need, for real.

sync; echo 3 | sudo tee /proc/sys/vm/drop_caches
2010-05-23 11:39:35
User: bandie91
Functions: echo sudo sync tee
8

where proc filesystem mounted under /proc

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__`
2010-05-07 16:03:42
User: trivoallan
Functions: awk grep sed sync
2

Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket.

sync; time `dd if=/dev/cciss/c0d1p1 of=/dev/null bs=1M count=10240`
sync; time `dd if=/dev/zero of=bigfile bs=1M count=2048 && sync`
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;
2009-10-30 16:19:16
User: uid0
Functions: cut echo grep sync
0

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

sync; echo 3 > /proc/sys/vm/drop_caches
time (dd if=/dev/zero of=blah.out bs=256M count=1 ; sync )
2009-07-14 20:19:23
User: tkunz
Functions: dd sync time
2

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.