Checks for RAM and SWAP Usage

check_memory_usage.sh

#!/bin/bash

echo "free -m:"
free -m

echo " "
echo "------"
echo "sysctl vm.swappiness :"
sysctl vm.swappiness


echo " "
echo "------"
echo "cat /proc/meminfo:"
cat /proc/meminfo

echo " "
echo "------"
echo "check swap usage sorted by process names:"
#cat /proc/18361/status | grep -i "VmSwap"
for file in /proc/*/status ; do awk '/VmSwap|Name/{printf $2 " " $3}END{ print ""}' $file; done | sort -k 2 -n -r | cat

# Additional Checks with root permissions:

#echo " "
#echo "------"
#echo "sudo cat /proc/slabinfo"
#sudo cat /proc/slabinfo

#echo " "
#echo "------"
#echo "sudo slabtop"
#sudo slabtop

Useful articles:
https://checkmk.com/de/blog/swap-monitoring
https://www.kernel.org/doc/Documentation/sysctl/vm.txt

REHL specific:
https://access.redhat.com/solutions/2435631
https://access.redhat.com/solutions/1384183
https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt

Change Swapiness:

Option 1: --> Temporary:

sudo sysctl vm.swappiness=10

Option 2: --> Permanently

echo "vm.swappiness=10" | sudo tee /etc/sysctl.d/500-custom-swapiness.conf