I have a problem between linux70 and udev-usb-sync. udev-usb-sync prevent the cache from writing to USB drives. See: Strict limit of write cache / 0s sync time policy for usb devices by default – #25 by linux-aarhus
Under Linux 7.0.0-rc6-1-MANJARO (and all earlier rcs) when copying a large file, such as an ISO, to a USB (I tried several, both A and C types and 2.0 to 3.1) file transfer is unacceptably slow – single and double digit KiBs/sec. – when it is also used udev-usb-sync.
Removal udev-usb-sync restore file transfer to the usual 60-65 MiBs/sec, but of course with cache writes.
conversely, with udev-usb-sync installed, but reverting to earlier kernels (6.18 or 6.19) file transfer also occurs at the expected higher rate, with uncached writes.
For now, since I like its benefits so much, I’m leaving udev-usb-sync installed and booting to older kernels when I need to copy a new ISO to my Ventoy USB.
Although I haven’t tested thoroughly, there seems to be no problem with smaller writes (all under 1 MiB).
inxi-zv8
System: Kernel: 7.0.0-rc6-1-MANJARO arch: x86_64 bits: 64 compiler: gcc v: 15.2.1 clocksource: tsc avail: acpi_pm parameters: BOOT_IMAGE=/boot/vmlinuz-7.0-x86_64 root=UUID=ea4f2edd-733a-4b30-a23d-c41894c4e38e rw rd.luks.key=/crypto_keyfile.bin rd.luks.name=8c31f8a9-1dd8-4081-ae58-442709a8aa73=root root=/dev/mapper/root rd.udev.log_priority=3 mitigations=off Desktop: KDE Plasma v: 6.6.3 tk: Qt v: N/A info: frameworks v: 6.24.0 wm: kwin_wayland vt: 2 dm: N/A Distro: Manjaro base: Arch Linux Machine: Type: Laptop System: Dell product: Latitude 5430 v: N/A serial: Chassis: type: 10 serial: Mobo: Dell model: 03G0RF v: A00 serial: part-nu: 0B04 uuid: Firmware: UEFI vendor: Dell v: 1.36.0 date: 12/23/2025 Battery: ID-1: BAT0 charge: 37.1 Wh (89.8%) condition: 41.3/41 Wh (100.8%) health: good temp: 29.5 C volts: 12.28 min: 11.25 model: SMP DELL 78FWY25 made: 2022-05-21 type: Li-poly serial: charging: status: not charging control: start: 50% end: 90% type: custom avail: adaptive,custom,fast,standard,trickle cycles: N/A Memory: System RAM: total: 32 GiB available: 31.03 GiB used: 3.53 GiB (11.4%) Message: For most reliable report, use superuser + dmidecode. Array-1: capacity: 64 GiB slots: 2 modules: 2 EC: None max-module-size: 32 GiB note: est. Device-1: DIMM A type: DDR4 detail: synchronous size: 16 GiB speed: 3200 MT/s volts: curr: 1 width (bits): data: 64 total: 64 manufacturer: 802C0000802C part-no: 8ATF2G64HZ-3G2E2 serial: Device-2: DIMM B type: DDR4 detail: synchronous size: 16 GiB speed: 3200 MT/s volts: curr: 1 width (bits): data: 64 total: 64 manufacturer: 802C0000802C part-no: 8ATF2G64HZ-3G2F1 serial: PCI Slots: Permissions: Unable to run dmidecode. Root privileges required. CPU: Info: model: 12th Gen Intel Core i7-1255U bits: 64 type: MST AMCP arch: Alder Lake level: v3 note: check built: 2021+ process: Intel 7 (10nm ESF) family: 6 model-id: 0x9A (154) stepping: 4 microcode: 0x43B Topology: cpus: 1x dies: 1 clusters: 4 cores: 10 threads: 12 mt: 2 tpc: 2 st: 8 smt: enabled cache: L1: 928 KiB desc: d-8x32 KiB, 2x48 KiB; i-2x32 KiB, 8x64 KiB L2: 6.5 MiB desc: 2x1.2 MiB, 2x2 MiB L3: 12 MiB desc: 1x12 MiB Speed (MHz): avg: 400 min/max: 400/4700:3500 scaling: driver: intel_pstate governor: powersave cores: 1: 400 2: 400 3: 400 4: 400 5: 400 6: 400 7: 400 8: 400 9: 400 10: 400 11: 400 12: 400 bogomips: 62668 Flags: 3dnowprefetch abm acpi adx aes aperfmperf apic arat arch_capabilities arch_lbr arch_perfmon art avx avx2 avx_vnni bmi1 bmi2 bts clflush clflushopt clwb cmov constant_tsc cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 dtherm dts epb ept ept_ad erms est f16c flexpriority flush_l1d fma fpu fsgsbase fsrm fxsr gfni hfi ht hwp hwp_act_window hwp_epp hwp_notify hwp_pkg_req ibpb ibrs ibrs_enhanced ibt ida intel_pt invpcid lahf_lm lm mca mce md_clear mmx monitor movbe movdir64b movdiri msr mtrr nonstop_tsc nopl nx ospke pae pat pbe pcid pclmulqdq pdcm pdpe1gb pebs pge pku pln pni popcnt pse pse36 pts rdpid rdrand rdseed rdtscp rep_good sdbg sep serialize sha_ni smap smep smx split_lock_detect ss ssbd sse sse2 sse4_1 sse4_2 ssse3 stibp syscall tm tm2 tpr_shadow tsc tsc_adjust tsc_deadline_timer tsc_known_freq umip user_shstk vaes vme vmx vnmi vpclmulqdq vpid waitpkg x2apic xgetbv1 xsave xsavec xsaveopt xsaves xtopology xtpr Vulnerabilities: Type: gather_data_sampling status: Not affected Type: ghostwrite status: Not affected Type: indirect_target_selection status: Not affected Type: itlb_multihit status: Not affected Type: l1tf status: Not affected Type: mds status: Not affected Type: meltdown status: Not affected Type: mmio_stale_data status: Not affected Type: old_microcode status: Not affected Type: reg_file_data_sampling status: Vulnerable Type: retbleed status: Not affected Type: spec_rstack_overflow status: Not affected Type: spec_store_bypass status: Vulnerable Type: spectre_v1 status: Vulnerable: __user pointer sanitization and usercopy barriers only; no swapgs barriers Type: spectre_v2 status: Vulnerable; IBPB: disabled; STIBP: disabled; PBRSB-eIBRS: Vulnerable; BHI: Vulnerable Type: srbds status: Not affected Type: tsa status: Not affected Type: tsx_async_abort status: Not affected Type: vmscape status: Vulnerable Graphics: Device-1: Intel Alder Lake-UP3 GT2 (Iris Xe Graphics) vendor: Dell driver: i915 v: kernel alternate: xe arch: Xe process: Intel 10nm built: 2021-22+ ports: active: eDP-1 off: DP-1 empty: DP-2,HDMI-A-1 bus-ID: 00:02.0 chip-ID: 8086:46a8 class-ID: 0300 Device-2: Microdia Integrated_Webcam_HD driver: uvcvideo type: USB rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 3-6:3 chip-ID: 0c45:6d1d class-ID: 0e02 Display: wayland server: X.org v: 1.21.1.21 with: Xwayland v: 24.1.9 compositor: kwin_wayland driver: X: loaded: modesetting alternate: fbdev,vesa dri: iris gpu: i915 display-ID: 0 Monitor-1: DP-1 model: LG (GoldStar) HDR 4K serial: built: 2023 res: 3840x2160 dpi: 163 gamma: 1.2 chroma: red: x: 0.682 y: 0.314 green: x: 0.278 y: 0.675 blue: x: 0.153 y: 0.047 white: x: 0.314 y: 0.329 size: 600x340mm (23.62x13.39") diag: 690mm (27.2") ratio: 16:9 modes: 3840x2160, 2560x1440, 1920x1080, 1600x900, 1280x1024, 1280x800, 1152x864, 1280x720, 1024x768, 800x600, 720x480, 640x480 Monitor-2: eDP-1 model: LG Display 0x068d built: 2020 res: mode: 1920x1080 hz: 60 scale: 100% (1) dpi: 158 gamma: 1.2 chroma: red: x: 0.596 y: 0.369 green: x: 0.349 y: 0.545 blue: x: 0.149 y: 0.110 white: x: 0.314 y: 0.329 size: 309x174mm (12.17x6.85") diag: 355mm (14") ratio: 16:9 modes: 1920x1080 EDID-Warnings: 1: parse_edid: unknown flag 0 API: EGL v: 1.5 hw: drv: intel iris platforms: device: 0 drv: iris device: 1 drv: swrast gbm: drv: iris surfaceless: drv: iris wayland: drv: iris x11: drv: iris API: OpenGL v: 4.6 compat-v: 4.5 vendor: intel mesa v: 26.0.4-arch1.1 glx-v: 1.4 direct-render: yes renderer: Mesa Intel Iris Xe Graphics (ADL GT2) device-ID: 8086:46a8 memory: 30.3 GiB unified: yes display-ID: :0.0 API: Vulkan v: 1.4.341 layers: 2 device: 0 type: integrated-gpu name: Intel Iris Xe Graphics (ADL GT2) driver: mesa intel v: 26.0.4-arch1.1 device-ID: 8086:46a8 surfaces: N/A Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo de: kscreen-console,kscreen-doctor wl: wayland-info x11: xdpyinfo,xprop Audio: Device-1: Intel Alder Lake PCH-P High Definition Audio vendor: Dell driver: snd_hda_intel v: kernel alternate: snd_soc_avs,snd_sof_pci_intel_tgl bus-ID: 00:1f.3 chip-ID: 8086:51c8 class-ID: 0403 API: ALSA v: k7.0.0-rc6-1-MANJARO status: kernel-api with: aoss type: oss-emulator tools: alsactl,alsamixer,amixer Server-1: sndiod v: N/A status: off tools: aucat,midicat,sndioctl Server-2: JACK v: 1.9.22 status: off tools: N/A Server-3: PipeWire v: 1.6.2 status: active with: 1: pipewire-pulse status: active 2: wireplumber status: active 3: pipewire-alsa type: plugin tools: pactl,pw-cat,pw-cli,wpctl Network: Device-1: Intel Ethernet I219-LM vendor: Dell driver: e1000e v: kernel port: N/A bus-ID: 00:1f.6 chip-ID: 8086:1a1e class-ID: 0200 IF: enp0s31f6 state: down mac: Device-2: Intel Wi-Fi 7 AX1775 /AX1790 /BE20 /BE401/BE1750 2x2 driver: iwlwifi v: kernel pcie: gen: 3 speed: 8 GT/s lanes: 1 link-max: gen: 4 speed: 16 GT/s bus-ID: 72:00.0 chip-ID: 8086:272b class-ID: 0280 IF: wlp114s0f0 state: up mac: IP v4: type: dynamic noprefixroute scope: global broadcast: IP v6: type: dynamic noprefixroute scope: global IP v6: type: noprefixroute scope: link IF-ID-1: proton0 state: unknown speed: N/A duplex: N/A mac: N/A IP v4: type: noprefixroute scope: global IF-ID-2: pvpnksintrf0 state: unknown speed: N/A duplex: N/A mac: IP v4: type: noprefixroute scope: global broadcast: IP v6: type: noprefixroute scope: global IP v6: type: noprefixroute scope: link Info: services: NetworkManager, systemd-timesyncd, wpa_supplicant WAN IP: Bluetooth: Device-1: Intel BE200 Bluetooth driver: btusb v: 0.8 type: USB rev: 2.0 speed: 12 Mb/s lanes: 1 mode: 1.1 bus-ID: 3-10:4 chip-ID: 8087:0036 class-ID: e001 Report: hciconfig ID: hci0 rfk-id: 2 state: up address: bt-v: 5.4 lmp-v: 13 sub-v: 409b hci-v: 13 rev: 409b class-ID: 6c010c Info: acl-mtu: 1021:4 sco-mtu: 96:6 link-policy: rswitch sniff link-mode: peripheral accept service-classes: rendering, capturing, audio, telephony Logical: Message: No logical block device data found. Device-1: root maj-min: 253:0 type: LUKS dm: dm-0 size: 128 GiB Components: p-1: nvme0n1p2 maj-min: 259:2 size: 128 GiB Device-2: luks-4f550296-12f7-40e2-a231-7b5f0aa9b7ea maj-min: 253:1 type: LUKS dm: dm-1 size: 3.6 TiB Components: p-1: nvme0n1p3 maj-min: 259:3 size: 3.6 TiB RAID: Message: No RAID data found. Drives: Local Storage: total: 3.84 TiB used: 710.38 GiB (18.1%) SMART Message: Unable to run smartctl. Root privileges required. ID-1: /dev/nvme0n1 maj-min: 259:0 model: XG7000-4TB 2280 size: 3.73 TiB block-size: physical: 512 B logical: 512 B speed: 63.2 Gb/s lanes: 4 tech: SSD serial: fw-rev: SN19172 temp: 43.9 C scheme: GPT ID-2: /dev/sda maj-min: 8:0 vendor: Samsung model: Type-C size: 119.51 GiB block-size: physical: 512 B logical: 512 B type: USB rev: 3.1 spd: 5 Gb/s lanes: 1 mode: 3.2 gen-1x1 tech: N/A serial: fw-rev: 1100 scheme: MBR SMART Message: Unknown USB bridge. Flash drive/Unsupported enclosure? Message: No optical or floppy data found. Partition: ID-1: / raw-size: 128 GiB size: 125.43 GiB (97.99%) used: 68.47 GiB (54.6%) fs: ext4 dev: /dev/dm-0 maj-min: 253:0 mapped: root label: N/A uuid: N/A ID-2: /Data raw-size: 3.6 TiB size: 3.54 TiB (98.40%) used: 602.73 GiB (16.6%) fs: ext4 dev: /dev/dm-1 maj-min: 253:1 mapped: luks-4f550296-12f7-40e2-a231-7b5f0aa9b7ea label: Data uuid: ac8d2e7b-87bd-40da-9feb-a11e79f0ca86 ID-3: /boot/efi raw-size: 2 GiB size: 2 GiB (99.80%) used: 85.9 MiB (4.2%) fs: vfat dev: /dev/nvme0n1p1 maj-min: 259:1 label: UEFI uuid: AAC3-479E ID-4: /run/media/brucew/Ventoy-C raw-size: 119.48 GiB size: 119.47 GiB (100.00%) used: 39.11 GiB (32.7%) fs: exfat dev: /dev/sda1 maj-min: 8:1 label: Ventoy-C uuid: B038-B41F Swap: Alert: No swap data was found. Unmounted: ID-1: /dev/sda2 maj-min: 8:2 size: 32 MiB fs: vfat label: VTOYEFI uuid: 626B-4255 USB: Hub-1: 1-0:1 info: hi-speed hub with single TT ports: 1 rev: 2.0 speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 chip-ID: 1d6b:0002 class-ID: 0900 Hub-2: 2-0:1 info: super-speed hub ports: 2 rev: 3.1 speed: 20 Gb/s (2.33 GiB/s) lanes: 2 mode: 3.2 gen-2x2 chip-ID: 1d6b:0003 class-ID: 0900 Device-1: 2-2:3 info: Silicon Motion - Taiwan (formerly Feiya ) Flash Drive type: mass storage driver: usb-storage interfaces: 1 rev: 3.1 speed: 5 Gb/s (596.0 MiB/s) lanes: 1 mode: 3.2 gen-1x1 power: 304mA chip-ID: 090c:1000 class-ID: 0806 serial: Hub-3: 3-0:1 info: hi-speed hub with single TT ports: 12 rev: 2.0 speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 chip-ID: 1d6b:0002 class-ID: 0900 Hub-4: 3-1:2 info: Realtek RTS5411 Hub ports: 5 rev: 2.1 speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 chip-ID: 0bda:5411 class-ID: 0900 Device-1: 3-6:3 info: Microdia Integrated_Webcam_HD type: video driver: uvcvideo interfaces: 2 rev: 2.0 speed: 480 Mb/s (57.2 MiB/s) lanes: 1 mode: 2.0 power: 500mA chip-ID: 0c45:6d1d class-ID: 0e02 Device-2: 3-10:4 info: Intel BE200 Bluetooth type: bluetooth driver: btusb interfaces: 2 rev: 2.0 speed: 12 Mb/s (1.4 MiB/s) lanes: 1 mode: 1.1 power: 100mA chip-ID: 8087:0036 class-ID: e001 Hub-5: 4-0:1 info: super-speed hub ports: 4 rev: 3.1 speed: 10 Gb/s (1.16 GiB/s) lanes: 1 mode: 3.2 gen-2x1 chip-ID: 1d6b:0003 class-ID: 0900 Sensors: System Temperatures: cpu: 49.0 C mobo: 44.0 C sodimm: 43.0 C Fan Speeds (rpm): cpu: 2090 Repos: Packages: 1466 pm: pacman pkgs: 1450 libs: 324 tools: pamac,paru,yay pm: flatpak pkgs: 16 Active pacman repo servers in: /etc/pacman.d/chaotic-mirrorlist 1: https://us-ny-mirror.chaotic.cx/$repo/$arch 2: https://us-mi-mirror.chaotic.cx/$repo/$arch 3: https://ca-1-mirror.chaotic.cx/$repo/$arch 4: https://ca-2-mirror.chaotic.cx/$repo/$arch 5: https://ca-3-mirror.chaotic.cx/$repo/$arch 6: https://ca-4-mirror.chaotic.cx/$repo/$arch 7: https://us-mirror.chaotic.cx/$repo/$arch 8: https://ca-mirror.chaotic.cx/$repo/$arch 9: https://geo-mirror.chaotic.cx/$repo/$arch 10: https://cdn-mirror.chaotic.cx/$repo/$arch Active pacman repo servers in: /etc/pacman.d/mirrorlist 1: https://nocix.mm.fcix.net/manjaro/unstable/$repo/$arch 2: https://cofractal-ewr.mm.fcix.net/manjaro/unstable/$repo/$arch 3: https://ohioix.mm.fcix.net/manjaro/unstable/$repo/$arch 4: https://repo.ialab.dsu.edu/manjaro/unstable/$repo/$arch 5: https://mirror.xenyth.net/manjaro/unstable/$repo/$arch 6: https://muug.ca/mirror/manjaro/unstable/$repo/$arch 7: https://ziply.mm.fcix.net/manjaro/unstable/$repo/$arch 8: https://mirrors.ocf.berkeley.edu/manjaro/unstable/$repo/$arch Processes: CPU top: 5 of 345 1: cpu: 7.1% command: syncthing pid: 1134 mem: 80.5 MiB (0.2%) 2: cpu: 6.3% command: vivaldi-bin pid: 5068 mem: 435.8 MiB (1.3%) 3: cpu: 4.7% command: vivaldi-bin pid: 5190 mem: 274.4 MiB (0.8%) 4: cpu: 4.3% command: vivaldi-bin pid: 5227 mem: 155.9 MiB (0.4%) 5: cpu: 2.8% command: kwin_wayland pid: 1175 mem: 236.0 MiB (0.7%) Memory top: 5 of 345 1: mem: 435.8 MiB (1.3%) command: vivaldi-bin pid: 5068 cpu: 6.3% 2: mem: 368.0 MiB (1.1%) command: plasmashell pid: 1362 cpu: 2.6% 3: mem: 274.4 MiB (0.8%) command: vivaldi-bin pid: 5190 cpu: 4.7% 4: mem: 236.0 MiB (0.7%) command: kwin_wayland pid: 1175 cpu: 2.8% 5: mem: 233.5 MiB (0.7%) command: protonvpn-app started-by: python pid: 1558 cpu: 0.5% Info: Processes: 345 Power: uptime: 6m states: freeze,mem,disk suspend: s2idle wakeups: 0 hibernate: platform avail: shutdown, reboot, suspend, test_resume image: 12.35 GiB services: org_kde_powerdevil, power-profiles-daemon, upowerd Init: systemd v: 260 default: graphical tool: systemctl Compilers: clang: 22.1.2 gcc: 15.2.1 Shell: Zsh v: 5.9 running-in: konsole inxi: 3.3.40
EDIT: Added inxi