merci madko, je vais creuser.
DU coup, les tunables ne sont appliqués que lorsque la machine n'est pas branchée au secteur ?
[root@localhost ~]# inxi -F
System: Host: localhost.localdomain Kernel: 4.19.13-300.fc29.x86_64 x86_64 bits: 64 Console: tty 1
Distro: Fedora release 29 (Twenty Nine)
Machine: Type: Laptop System: ASUSTeK product: X510UAR v: 1.0 serial: JAN0CX03J237410
Mobo: ASUSTeK model: X510UAR v: 1.0 serial: QCCXKG1QL84101928 UEFI: American Megatrends v: X510UAR.309
date: 07/24/2018
Battery: ID-1: BAT0 charge: 9.9 Wh condition: 39.2/43.0 Wh (91%)
CPU: Topology: Quad Core model: Intel Core i5-8250U bits: 64 type: MT MCP L2 cache: 6144 KiB
Speed: 900 MHz min/max: 400/3400 MHz Core speeds (MHz): 1: 900 2: 900 3: 900 4: 900 5: 900 6: 900 7: 900
8: 900
Graphics: Device-1: Intel UHD Graphics 620 driver: i915 v: kernel
Display: server: X.org 1.20.3 driver: modesetting unloaded: fbdev,vesa tty: 125x56
Message: Advanced graphics data unavailable in console for root.
Audio: Device-1: Intel Sunrise Point-LP HD Audio driver: snd_hda_intel
Sound Server: ALSA v: k4.19.13-300.fc29.x86_64
Network: Device-1: Intel Wireless 8265 / 8275 driver: iwlwifi
IF: wlp2s0 state: up mac: 18:1d:ea:33:e7:fd
Drives: Local Storage: total: 1.14 TiB used: 729.33 GiB (62.3%)
ID-1: /dev/sda vendor: Toshiba model: MQ04ABF100 size: 931.51 GiB
ID-2: /dev/sdb vendor: Micron model: 1100 MTFDDAV256TBN size: 238.47 GiB
Partition: ID-1: / size: 58.81 GiB used: 11.25 GiB (19.1%) fs: ext4 dev: /dev/sdb5
ID-2: /boot size: 975.9 MiB used: 153.6 MiB (15.7%) fs: ext4 dev: /dev/sdb2
ID-3: /home size: 165.82 GiB used: 10.96 GiB (6.6%) fs: ext4 dev: /dev/sdb3
ID-4: swap-1 size: 7.80 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/sdb4
Sensors: System Temperatures: cpu: 43.0 C mobo: N/A
Fan Speeds (RPM): N/A
Info: Processes: 265 Uptime: 1h 22m Memory: 7.67 GiB used: 2.48 GiB (32.3%) Init: systemd runlevel: 5 Shell: bash