Steam downloads constantly spike and drop in speed on Arch Linux

[ocupadordecasas]

Your system information

• Steam client version:Latest stable (installed from pacman)
• Distribution : Arch Linux
• Opted into Steam client beta?: No
• Have you checked for system updates?: Yes
• Steam Logs: will attach if needed
• GPU: RTX 5070 ti

Steam downloads are extremely unstable and constantly fluctuate in speed.

When I first installed Arch Linux everything worked perfectly and Steam downloads were fast and stable. However, after about a day the download behavior changed and now the speed constantly goes up and down.

Example behavior:

• Download speed spikes very high
• Then drops significantly
• Then increases again
• This repeats continuously

Because of this, games that should download in a few minutes can take 30–40 minutes even for only a few GB.

While downloading I can see that disk writes spike very high (sometimes close to 1 GB/s) and then drop to around ~200 MB/s, and at the same time the network download speed drops as well.

Important notes:

• My NVMe disk speed is fine
• My internet connection is fine
• This issue did NOT happen on other Linux distributions I used before (for example CachyOS)

Things I already tried:

• Changing Steam download region
• Restarting Steam and clearing configs
• Regenerating Arch mirrors
• Changing NVMe I/O scheduler (kyber, bfq, mq-deadline)
• Checking vm.dirty_ratio and vm.dirty_background_ratio kernel parameters
• Checking active Steam connections with ss -tupn

None of these changes solved the issue.

Steps for reproducing this issue:

1. Install Steam on Arch Linux
2. Start downloading a game
3. Observe the network graph constantly fluctuating and download speed repeatedly dropping and increasing

System info

System:
Kernel: 6.18.13-zen1-1-zen arch: x86_64 bits: 64
Desktop: Hyprland v: 0.54.1 Distro: Arch Linux
Machine:
Type: Desktop Mobo: Micro-Star model: MPG B550 GAMING PLUS (MS-7C56) v: 1.0
serial: Firmware: UEFI vendor: American Megatrends LLC.
v: 1.L1 date: 09/19/2025
CPU:
Info: 8-core model: AMD Ryzen 7 5800X bits: 64 type: MT MCP cache: L2: 4 MiB
Speed (MHz): avg: 3474 min/max: 556/4854 cores: 1: 3474 2: 3474 3: 3474
4: 3474 5: 3474 6: 3474 7: 3474 8: 3474 9: 3474 10: 3474 11: 3474 12: 3474
13: 3474 14: 3474 15: 3474 16: 3474
Graphics:
Device-1: NVIDIA GB203 [GeForce RTX 5070 Ti] driver: nvidia v: 590.48.01
Display: wayland server: X.org v: 1.21.1.21 with: Xwayland v: 24.1.9
compositor: Hyprland v: 0.54.1 driver: X: loaded: nvidia
unloaded: modesetting gpu: nv_platform,nvidia,nvidia-nvswitch resolution:
1: 2560x144060Hz 2: 1920x1080144Hz
API: EGL Message: EGL data requires eglinfo. Check --recommends.
Info: Tools: gpu: nvidia-smi wl: nwg-displays x11: xprop,xrandr
Audio:
Device-1: NVIDIA GB203 High Definition Audio driver: snd_hda_intel
Device-2: Advanced Micro Devices [AMD] Starship/Matisse HD Audio
driver: snd_hda_intel
Device-3: Corsair HS80 RGB USB Gaming Headset
driver: hid-generic,snd-usb-audio,usbhid type: USB
Device-4: Corsair HS80 RGB Wireless Gaming Receiver
driver: hid-generic,snd-usb-audio,usbhid type: USB
API: ALSA v: k6.18.13-zen1-1-zen status: kernel-api
Server-1: PipeWire v: 1.4.10 status: active
Network:
Device-1: Realtek RTL8111/8168/8211/8411 PCI Express Gigabit Ethernet
driver: r8169
IF: enp42s0 state: up speed: 1000 Mbps duplex: full mac:
Drives:
Local Storage: total: 1.36 TiB used: 57.12 GiB (4.1%)
ID-1: /dev/nvme0n1 vendor: KIOXIA model: EXCERIA SSD size: 465.76 GiB
ID-2: /dev/nvme1n1 vendor: KIOXIA model: EXCERIA G2 SSD size: 931.51 GiB
Partition:
ID-1: / size: 464.76 GiB used: 56.98 GiB (12.3%) fs: btrfs
dev: /dev/nvme0n1p2
ID-2: /boot size: 1022 MiB used: 148.1 MiB (14.5%) fs: vfat
dev: /dev/nvme0n1p1
ID-3: /home size: 464.76 GiB used: 56.98 GiB (12.3%) fs: btrfs
dev: /dev/nvme0n1p2
ID-4: /var/log size: 464.76 GiB used: 56.98 GiB (12.3%) fs: btrfs
dev: /dev/nvme0n1p2
Swap:
ID-1: swap-1 type: zram size: 15.63 GiB used: 12 KiB (0.0%) dev: /dev/zram0
Sensors:
System Temperatures: cpu: 48.2 C mobo: N/A
Fan Speeds (rpm): N/A
Info:
Memory: total: 32 GiB available: 31.26 GiB used: 5.63 GiB (18.0%)
Processes: 375 Uptime: 58m Shell: Bash inxi: 3.3.40