bash script to calculate ksm stats in kb

ksmstat

#!/bin/bash

if [ "$1" != "" ]; then


echo "
----------------------------------------------------------------------------
http://www.kernel.org/doc/Documentation/vm/ksm.txt :

The effectiveness of KSM and MADV_MERGEABLE is shown in /sys/kernel/mm/ksm/:

pages_shared     - how many shared pages are being used
pages_sharing    - how many more sites are sharing them i.e. how much saved
pages_unshared   - how many pages unique but repeatedly checked for merging
pages_volatile   - how many pages changing too fast to be placed in a tree
full_scans       - how many times all mergeable areas have been scanned

A high ratio of pages_sharing to pages_shared indicates good sharing, but
a high ratio of pages_unshared to pages_sharing indicates wasted effort.
pages_volatile embraces several different kinds of activity, but a high
proportion there would also indicate poor use of madvise MADV_MERGEABLE.
----------------------------------------------------------------------------
"
fi;


pages_shared=`cat /sys/kernel/mm/ksm/pages_shared`;
pages_sharing=`cat /sys/kernel/mm/ksm/pages_sharing`;
pages_unshared=`cat /sys/kernel/mm/ksm/pages_unshared`;
pages_volatile=`cat /sys/kernel/mm/ksm/pages_volatile`;
page_size=`getconf PAGESIZE`;

ratio_sharing_to_shared=$(echo "scale=2;$pages_sharing / $pages_shared"|bc);
ratio_unshared_to_sharing=$(echo "scale=2;$pages_unshared / $pages_sharing"|bc);
saved=$(echo "scale=0;$pages_sharing * $page_size"|bc);

saved=$(expr $saved / 1048576);

printf "Shared\tSharing\tUnshared\tVolatile\tSharing:Shared\tUnshared:Sharing\tSaved\n";
printf "%'d\t%'d\t%'d\t\t%'d\t\t%'f:1\t%'f:1\t\t%'dM\n" $pages_shared $pages_sharing $pages_unshared $pages_volatile $ratio_sharing_to_shared $ratio_unshared_to_sharing $saved;

Whenever I run the script my output looks like this:
`Shared Sharing Unshared Volatile Sharing:Shared Unshared:Sharing Saved

/opt/ksmstat.sh: Zeile 40: printf: 26.38: Ungültige Zahl.
/opt/ksmstat.sh: Zeile 40: printf: .26: Ungültige Zahl.
30.263 798.389 212.168 1.063.240 0,000000:1 0,000000:1 3.118M
`

Zeile = line
Ungültigle Zahl = invalid number

Also getting the error:

++ cat /sys/kernel/mm/uksm/pages_shared
+ pages_shared=3629
++ cat /sys/kernel/mm/uksm/pages_sharing
+ pages_sharing=55277
++ cat /sys/kernel/mm/uksm/pages_unshared
+ pages_unshared=168436
++ cat /sys/kernel/mm/uksm/pages_volatile
cat: /sys/kernel/mm/uksm/pages_volatile: No such file or directory
+ pages_volatile=
++ getconf PAGESIZE
+ page_size=4096
++ echo 'scale=2;55277 / 3629'
++ bc
+ ratio_sharing_to_shared=15.23
++ echo 'scale=2;168436 / 55277'
++ bc
+ ratio_unshared_to_sharing=3.04
++ echo 'scale=0;55277 * 4096'
++ bc
+ saved=226414592
++ expr 226414592 / 1048576
+ saved=215
+ printf 'Shared\tSharing\tUnshared\tVolatile\tSharing:Shared\tUnshared:Sharing\tSaved\n'
Shared  Sharing Unshared        Volatile        Sharing:Shared  Unshared:Sharing        Saved                                                                                                
+ printf '%'\''d\t%'\''d\t%'\''d\t\t%'\''d\t\t%'\''f:1\t%'\''f:1\t\t%'\''dM\n' 3629 55277 168436 15.23 3.04 215                                                                              
ksm.sh: line 40: printf: 15.23: invalid number                                                                                                                                               
ksm.sh: line 40: printf: 3.04: invalid number                                                                                                                                                
3.629   55.277  168.436         15              0,000000:1      215,000000:1            0M

So I wrote this:

#!/bin/bash

[ -e /sys/kernel/mm/uksm/ ] && ksm=uksm
[ -e /sys/kernel/mm/ksm/ ] && ksm=ksm

pagesize=$(getconf PAGESIZE)

echo $(($pagesize*$(cat /sys/kernel/mm/$ksm/pages_sharing)/1024))kb scanned
echo $(($pagesize*$(cat /sys/kernel/mm/$ksm/pages_shared)/1024))kb shared=saved
echo $(($pagesize*$(cat /sys/kernel/mm/$ksm/pages_unshared)/1024))kb not shared

To fix "printf: ...: invalid number" errors add this line to start of script:
LC_NUMERIC="en_US.UTF-8"

Nice!