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Commands using sync

Terminal - Commands using sync - 14 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

2013-02-27 12:39:20

User: szimbaro

Functions: sleep sync

Up
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Clean memory and SO cache

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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

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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

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

2011-10-18 15:22:25

User: mariusbutuc

Functions: echo sudo sync tee

Tags: cache

Up
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Clear filesystem memory cache

Found here: http://ubuntuforums.org/showthread.php?t=589975

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sync && echo 1 > /proc/sys/vm/drop_caches

2011-06-10 07:32:28

User: KeePon

Functions: echo sync

Tags: memory ram kernel sync cache free

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clean up memory of unnecessary things (Kernerl 2.6.16 or newer)

run sync first to flush useful things out to disk!!!

To free pagecache:

echo 1 > /proc/sys/vm/drop_caches

To free dentries and inodes:

echo 2 > /proc/sys/vm/drop_caches

To free pagecache, dentries and inodes:

echo 3 > /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

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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.

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

2010-05-23 11:39:35

User: bandie91

Functions: echo sudo sync tee

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clean up memory on linux

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

Tags: bash ruby s3 capistrano cdn

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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.

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

2009-11-19 10:34:13

User: w00binda

Functions: sync time

Tags: dd benchmark

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Testing reading speed with dd

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

2009-11-19 10:29:03

User: w00binda

Functions: sync time

Tags: dd benchmark

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Testing writing speed with dd

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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

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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.

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

2009-08-20 17:28:56

User: lunarblu

Functions: echo sync

Up
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clear the cache from memory

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

2009-08-05 23:44:34

User: ricardoarguello

Functions: echo free sync

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Release memory used by the Linux kernel on caches

The Linux kernel uses unused memory in caches. When you execute "free" you never get the "real" available memory.

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

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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.

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

2009-02-19 15:54:22

User: skygreg

Functions: echo sync

Up
Down

Empty the linux buffer cache

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