En complément de ça :
https://famille-michon.fr/links/?X3TlPw
et ça (swappiness) :
https://famille-michon.fr/links/?WdjPUA
Sinon, les infos intéressantes de ce post :
"""
sudo gedit /etc/rc.local
##Add the following above "exit 0"##
echo 0 > /sys/block/sda/queue/add_random (prevents the I/O of your SSD from cotributing to the entropy pool)
echo 0 > /sys/block/sda/queue/rotational (informs Ubuntu your are using an SSD)
echo 2 > /sys/block/sda/queue/rq_affinity (only use when you have a powerful CPU , if you experience lagging while gaming you can undo the changes by removing this line)
[...]
Moving Temporary Files to Memory (RAM):
[...]
tmpfs /tmp tmpfs defaults,noatime,size=1G,mode=1777 0 0
tmpfs /var/tmp tmpfs defaults,noatime,mode=1777 0 0
tmpfs /var/log tmpfs defaults,noatime,mode=0755 0 0
tmpfs /var/log/apt tmpfs defaults,noatime 0 0
"""