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Commands tagged ram from sorted by
Terminal - Commands tagged ram - 14 results
ram() { mt=/mnt/ram && grep "$mt" < /proc/mts > /dev/null; if [ $? -eq 0 ] ; then read -p"Enter to Remove Ram Partition ";sudo umount "$mt" && echo $mt 0; else sudo mt -t tmpfs tmpfs "$mt" -o size=$(( ${1:-1} * 1024 ))m && echo $mt '-' "${1:-1}"gb; fi; }
2013-12-13 05:22:02
User: snipertyler
Functions: echo grep mt read sudo umount
Tags: sudo ram tmpfs
2

Creates a temporary ram partition

To use:

ram 3

to make a 3gb partition (Defaults to 1gb)

sudo dmidecode --type 17
2013-04-18 20:13:07
User: FadeMind
Functions: sudo
Tags: ram dmidecode
0

Advanced information about RAM.

dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend
2013-01-15 18:47:21
User: totti
1
dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend
pmi action suspend
free -m | awk '/cache:/ {print $4}'
2012-03-13 19:54:26
User: felixhummel
Functions: awk free
Tags: ram free
0

Does not output the word "shared" so you can easily store this number in a variable.

cat <file> > /dev/null
2011-11-12 15:45:27
User: totti
Functions: cat
Tags: ram file cache
8

Best result when file size less than half of RAM size

/usr/sbin/dmidecode | perl -lne 'print $1 if /Current\s+Speed:\s+(\d+\s+MHz)/'
grep '^MemFree:' /proc/meminfo | awk '{ mem=($2)/(1024) ; printf "%0.0f MB\n", mem }'
2010-06-30 18:33:29
User: dbbolton
Functions: awk grep printf
4

This will show the amount of physical RAM that is left unused by the system.

free -m | awk '/buffer/ {print $4}'
2010-06-27 23:30:27
User: DaveQB
Functions: awk free
Tags: ram free
3

Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed.

Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed.

I just noticed the free command is not on my OpenBSD box.

free -m | awk '/Mem/ {print $4}'
dd if=/dev/zero of=junk bs=1M count=1K
2009-11-01 23:45:51
User: guedesav
Functions: dd
Tags: dd ram rm
-11

This is an useful command for when your OS is reporting less free RAM than it actually has. In case terminated processes did not free their variables correctly, the previously allocated RAM might make a bit sluggis over time.

This command then creates a huge file made out of zeroes and then removes it, thus freeing the amount of memory occupied by the file in the RAM.

In this example, the sequence will free up to 1GB(1M * 1K) of unused RAM. This will not free memory which is genuinely being used by active processes.

sudo cat /proc/kcore | strings | awk 'length > 20' | less
2009-03-09 02:19:47
User: nesquick
Functions: awk cat strings sudo
Tags: cat ram strings
15

This command lets you see and scroll through all of the strings that are stored in the RAM at any given time. Press space bar to scroll through to see more pages (or use the arrow keys etc).

Sometimes if you don't save that file that you were working on or want to get back something you closed it can be found floating around in here!

The awk command only shows lines that are longer than 20 characters (to avoid seeing lots of junk that probably isn't "human readable").

If you want to dump the whole thing to a file replace the final '| less' with '> memorydump'. This is great for searching through many times (and with the added bonus that it doesn't overwrite any memory...).

Here's a neat example to show up conversations that were had in pidgin (will probably work after it has been closed)...

sudo cat /proc/kcore | strings | grep '([0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\})'

(depending on sudo settings it might be best to run

sudo su

first to get to a # prompt)