w

ps aux
ps ux --sort +vsize | head -5
ps aux --sort -pcpu | head -5

df -h

du -ks * | sort -rn | more

netstat -ntlp

top
free -m

#Check IO Performance

iostat -kx 2
vmstat 2 10
mpstat 2 10

#List all the open files to active process

lsof -p 3063