Clé USB Transcend 4Go - pas d'USB 2.0 !?!?

Salut à tous !

Je suis (depuis Noël) l’heureux possesseur d’une clé USB Transcend JF V30 d’une capacité de 4Go.
Jusque là tout va bien… Là où ça se complique, c’est que sous Debian Sid (c’est également le cas sous Xubuntu Edgy) j’ai une vitesse de transmission extrêmement lente… sad

Voilà… Si quelqu’un sait pourquoi… Et comment faire pour remédier à ce problème ?
Parce que c’est vraiment désespérant de devoir rebooter sous un XP que je garde dans un coin pour les jeux, juste pour copier un gros fichier…

Tous vos éclaircissements sont les bienvenus ! Merci !

Juste quelques précisions si ca peut aider quelqu’un à me dépanner :

l’USB 2.0 est en fait bien reconnu, le transfert débute normalement (même très rapidement) mais à partir d’un moment, cela ralenti considérablement et stagne… et finit par prendre un temps fou…

Voilà… Est-ce que cela peut venir d’une mauvaise gestion du tampon de copie ou quelque chose du genre? Et si c’est le cas que faire?

Merci

je viens de copier 25 Go d’un coup sur mon lecteur divx/mp3 en USB 2.0 à partir de la debian Etch et c’est allé très vite …

Regarde ce que te donne comme messages dmesg et /var/log/syslog…

Bonjour, la commande dmesg me donne le résultat suivant :

Linux version 2.6.18-3-686 (Debian 2.6.18-8) (waldi@debian.org) (gcc version 4.1 .2 20061115 (prerelease) (Debian 4.1.1-20)) #1 SMP Sun Dec 10 19:37:06 UTC 2006 BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 000000000009fc00 (usable) BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved) BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 000000001fff0000 (usable) BIOS-e820: 000000001fff0000 - 000000001fff8000 (ACPI data) BIOS-e820: 000000001fff8000 - 0000000020000000 (ACPI NVS) BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved) BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved) BIOS-e820: 00000000fff80000 - 0000000100000000 (reserved) 0MB HIGHMEM available. 511MB LOWMEM available. On node 0 totalpages: 131056 DMA zone: 4096 pages, LIFO batch:0 Normal zone: 126960 pages, LIFO batch:31 DMI 2.3 present. ACPI: RSDP (v000 AMI ) @ 0x000fa8c0 ACPI: RSDT (v001 AMIINT VIA_K7 0x00000010 MSFT 0x00000097) @ 0x1fff0000 ACPI: FADT (v001 AMIINT VIA_K7 0x00000011 MSFT 0x00000097) @ 0x1fff0030 ACPI: MADT (v001 AMIINT VIA_K7 0x00000009 MSFT 0x00000097) @ 0x1fff00c0 ACPI: DSDT (v001 VIA K7VT4 0x00001000 MSFT 0x0100000d) @ 0x00000000 ACPI: PM-Timer IO Port: 0x808 ACPI: Local APIC address 0xfee00000 ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled) Processor #0 6:8 APIC version 16 ACPI: IOAPIC (id[0x02] address[0xfec00000] gsi_base[0]) IOAPIC[0]: apic_id 2, version 3, address 0xfec00000, GSI 0-23 ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) ACPI: IRQ0 used by override. ACPI: IRQ2 used by override. ACPI: IRQ9 used by override. Enabling APIC mode: Flat. Using 1 I/O APICs Using ACPI (MADT) for SMP configuration information Allocating PCI resources starting at 30000000 (gap: 20000000:dec00000) Detected 1832.875 MHz processor. Built 1 zonelists. Total pages: 131056 Kernel command line: root=/dev/hda1 ro mapped APIC to ffffd000 (fee00000) mapped IOAPIC to ffffc000 (fec00000) Enabling fast FPU save and restore... done. Enabling unmasked SIMD FPU exception support... done. Initializing CPU#0 PID hash table entries: 2048 (order: 11, 8192 bytes) Console: colour VGA+ 80x25 Dentry cache hash table entries: 65536 (order: 6, 262144 bytes) Inode-cache hash table entries: 32768 (order: 5, 131072 bytes) Memory: 511544k/524224k available (1543k kernel code, 12036k reserved, 574k data , 196k init, 0k highmem) Checking if this processor honours the WP bit even in supervisor mode... Ok. Calibrating delay using timer specific routine.. 3669.75 BogoMIPS (lpj=7339505) Security Framework v1.0.0 initialized SELinux: Disabled at boot. Capability LSM initialized Mount-cache hash table entries: 512 CPU: After generic identify, caps: 0383fbff c1cbfbff 00000000 00000000 00000000 00000000 00000000 CPU: After vendor identify, caps: 0383fbff c1cbfbff 00000000 00000000 00000000 0 0000000 00000000 CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line) CPU: L2 Cache: 256K (64 bytes/line) CPU: After all inits, caps: 0383fbff c1cbfbff 00000000 00000420 00000000 0000000 0 00000000 Intel machine check architecture supported. Intel machine check reporting enabled on CPU#0. Compat vDSO mapped to ffffe000. Checking 'hlt' instruction... OK. SMP alternatives: switching to UP code Freeing SMP alternatives: 16k freed ACPI: Core revision 20060707 CPU0: AMD Sempron(tm) 2600+ stepping 01 Total of 1 processors activated (3669.75 BogoMIPS). ENABLING IO-APIC IRQs ..TIMER: vector=0x31 apic1=0 pin1=2 apic2=-1 pin2=-1 Brought up 1 CPUs migration_cost=0 checking if image is initramfs... it is Freeing initrd memory: 4865k freed NET: Registered protocol family 16 ACPI: bus type pci registered PCI: PCI BIOS revision 2.10 entry at 0xfda71, last bus=1 PCI: Using configuration type 1 Setting up standard PCI resources ACPI: Interpreter enabled ACPI: Using IOAPIC for interrupt routing ACPI: PCI Root Bridge [PCI0] (0000:00) PCI: Probing PCI hardware (bus 00) Boot video device is 0000:01:00.0 ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] ACPI: Power Resource [URP1] (off) ACPI: Power Resource [URP2] (off) ACPI: Power Resource [FDDP] (off) ACPI: Power Resource [LPTP] (off) ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 7 10 *11 12 14 15) ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 7 *10 11 12 14 15) ACPI: PCI Interrupt Link [LNKC] (IRQs *3 4 5 7 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 *5 7 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKE] (IRQs 3 4 5 7 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKF] (IRQs 3 4 5 7 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKG] (IRQs 3 4 5 7 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKH] (IRQs 3 4 5 7 10 11 12 14 15) *0, disabled. Linux Plug and Play Support v0.97 (c) Adam Belay pnp: PnP ACPI init pnp: PnP ACPI: found 12 devices PnPBIOS: Disabled by ACPI PNP PCI: Using ACPI for IRQ routing PCI: If a device doesn't work, try "pci=routeirq". If it helps, post a report PCI: Bridge: 0000:00:01.0 IO window: disabled. MEM window: dde00000-dfefffff PREFETCH window: d5d00000-ddcfffff PCI: Setting latency timer of device 0000:00:01.0 to 64 NET: Registered protocol family 2 IP route cache hash table entries: 4096 (order: 2, 16384 bytes) TCP established hash table entries: 16384 (order: 5, 131072 bytes) TCP bind hash table entries: 8192 (order: 4, 65536 bytes) TCP: Hash tables configured (established 16384 bind 8192) TCP reno registered audit: initializing netlink socket (disabled) audit(1169116933.840:1): initialized VFS: Disk quotas dquot_6.5.1 Dquot-cache hash table entries: 1024 (order 0, 4096 bytes) Initializing Cryptographic API io scheduler noop registered io scheduler anticipatory registered io scheduler deadline registered io scheduler cfq registered (default) PCI: Bypassing VIA 8237 APIC De-Assert Message isapnp: Scanning for PnP cards... isapnp: No Plug & Play device found Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A 00:02: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A RAMDISK driver initialized: 16 RAM disks of 8192K size 1024 blocksize PNP: PS/2 Controller [PNP0303:PS2K,PNP0f13:PS2M] at 0x60,0x64 irq 1,12 serio: i8042 AUX port at 0x60,0x64 irq 12 serio: i8042 KBD port at 0x60,0x64 irq 1 mice: PS/2 mouse device common for all mice TCP bic registered NET: Registered protocol family 1 NET: Registered protocol family 17 NET: Registered protocol family 8 NET: Registered protocol family 20 Using IPI No-Shortcut mode ACPI: (supports S0 S1 S4 S5) Freeing unused kernel memory: 196k freed Time: tsc clocksource has been installed. input: AT Translated Set 2 keyboard as /class/input/input0 SCSI subsystem initialized libata version 2.00 loaded. Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2 ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx VP_IDE: IDE controller at PCI slot 0000:00:0f.1 ACPI: PCI Interrupt 0000:00:0f.1[A] -> GSI 20 (level, low) -> IRQ 169 PCI: VIA IRQ fixup for 0000:00:0f.1, from 255 to 9 VP_IDE: chipset revision 6 VP_IDE: not 100% native mode: will probe irqs later VP_IDE: VIA vt8237 (rev 00) IDE UDMA133 controller on pci0000:00:0f.1 ide0: BM-DMA at 0xfc00-0xfc07, BIOS settings: hda:DMA, hdb:pio ide1: BM-DMA at 0xfc08-0xfc0f, BIOS settings: hdc:DMA, hdd:pio Probing IDE interface ide0... usbcore: registered new driver usbfs usbcore: registered new driver hub USB Universal Host Controller Interface driver v3.0 via-rhine.c:v1.10-LK1.4.1 July-24-2006 Written by Donald Becker hda: Maxtor 6L200P0, ATA DISK drive ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 Probing IDE interface ide1... hdc: PIONEER DVD-RW DVR-108, ATAPI CD/DVD-ROM drive ide1 at 0x170-0x177,0x376 on irq 15 sata_via 0000:00:0f.0: version 2.0 ACPI: PCI Interrupt 0000:00:0f.0[B] -> GSI 20 (level, low) -> IRQ 169 sata_via 0000:00:0f.0: routed to hard irq line 10 ata1: SATA max UDMA/133 cmd 0xEC00 ctl 0xE802 bmdma 0xDC00 irq 169 ata2: SATA max UDMA/133 cmd 0xE400 ctl 0xE002 bmdma 0xDC08 irq 169 scsi0 : sata_via ata1: SATA link down 1.5 Gbps (SStatus 0 SControl 300) ATA: abnormal status 0x7F on port 0xEC07 scsi1 : sata_via ata2: SATA link down 1.5 Gbps (SStatus 0 SControl 300) ATA: abnormal status 0x7F on port 0xE407 ACPI: PCI Interrupt 0000:00:10.0[A] -> GSI 21 (level, low) -> IRQ 177 PCI: VIA IRQ fixup for 0000:00:10.0, from 11 to 1 uhci_hcd 0000:00:10.0: UHCI Host Controller uhci_hcd 0000:00:10.0: new USB bus registered, assigned bus number 1 uhci_hcd 0000:00:10.0: irq 177, io base 0x0000c800 usb usb1: configuration #1 chosen from 1 choice hub 1-0:1.0: USB hub found hub 1-0:1.0: 2 ports detected ACPI: PCI Interrupt 0000:00:10.1[A] -> GSI 21 (level, low) -> IRQ 177 PCI: VIA IRQ fixup for 0000:00:10.1, from 11 to 1 uhci_hcd 0000:00:10.1: UHCI Host Controller uhci_hcd 0000:00:10.1: new USB bus registered, assigned bus number 2 uhci_hcd 0000:00:10.1: irq 177, io base 0x0000cc00 usb usb2: configuration #1 chosen from 1 choice hub 2-0:1.0: USB hub found hub 2-0:1.0: 2 ports detected ACPI: PCI Interrupt 0000:00:10.2[B] -> GSI 21 (level, low) -> IRQ 177 PCI: VIA IRQ fixup for 0000:00:10.2, from 10 to 1 uhci_hcd 0000:00:10.2: UHCI Host Controller uhci_hcd 0000:00:10.2: new USB bus registered, assigned bus number 3 uhci_hcd 0000:00:10.2: irq 177, io base 0x0000d000 usb usb3: configuration #1 chosen from 1 choice hub 3-0:1.0: USB hub found hub 3-0:1.0: 2 ports detected ACPI: PCI Interrupt 0000:00:10.3[B] -> GSI 21 (level, low) -> IRQ 177 PCI: VIA IRQ fixup for 0000:00:10.3, from 10 to 1 uhci_hcd 0000:00:10.3: UHCI Host Controller uhci_hcd 0000:00:10.3: new USB bus registered, assigned bus number 4 uhci_hcd 0000:00:10.3: irq 177, io base 0x0000d400 usb usb4: configuration #1 chosen from 1 choice hub 4-0:1.0: USB hub found hub 4-0:1.0: 2 ports detected ACPI: PCI Interrupt 0000:00:12.0[A] -> GSI 23 (level, low) -> IRQ 185 eth0: VIA Rhine II at 0x1c000, 00:0b:6a:99:e1:11, IRQ 185. eth0: MII PHY found at address 1, status 0x7869 advertising 05e1 Link 45e1. ACPI: PCI Interrupt 0000:00:10.4[C] -> GSI 21 (level, low) -> IRQ 177 PCI: VIA IRQ fixup for 0000:00:10.4, from 3 to 1 ehci_hcd 0000:00:10.4: EHCI Host Controller ehci_hcd 0000:00:10.4: new USB bus registered, assigned bus number 5 ehci_hcd 0000:00:10.4: irq 177, io mem 0xdfffbe00 ehci_hcd 0000:00:10.4: USB 2.0 started, EHCI 1.00, driver 10 Dec 2004 usb usb5: configuration #1 chosen from 1 choice hub 5-0:1.0: USB hub found hub 5-0:1.0: 8 ports detected hda: max request size: 512KiB hda: 398297088 sectors (203928 MB) w/8192KiB Cache, CHS=24792/255/63, UDMA(33) hda: cache flushes supported hda: hda1 hda2 hda3 hda4 hdc: ATAPI 40X DVD-ROM DVD-R CD-R/RW drive, 2000kB Cache, UDMA(33) Uniform CD-ROM driver Revision: 3.20 ReiserFS: hda1: found reiserfs format "3.6" with standard journal ReiserFS: hda1: using ordered data mode ReiserFS: hda1: journal params: device hda1, size 8192, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30 ReiserFS: hda1: checking transaction log (hda1) ReiserFS: hda1: Using r5 hash to sort names pci_hotplug: PCI Hot Plug PCI Core version: 0.5 shpchp: Standard Hot Plug PCI Controller Driver version: 0.4 input: PC Speaker as /class/input/input1 Linux agpgart interface v0.101 (c) Dave Jones agpgart: Detected VIA KT400/KT400A/KT600 chipset agpgart: AGP aperture is 64M @ 0xe0000000 Real Time Clock Driver v1.12ac Floppy drive(s): fd0 is 1.44M parport: PnPBIOS parport detected. parport0: PC-style at 0x378 (0x778), irq 7, dma 0 [PCSPP,TRISTATE,COMPAT,EPP,ECP ,DMA] FDC 0 is a post-1991 82077 ACPI: PCI Interrupt 0000:00:11.5[C] -> GSI 22 (level, low) -> IRQ 193 PCI: Setting latency timer of device 0000:00:11.5 to 64 input: ImExPS/2 Logitech Wheel Mouse as /class/input/input2 ts: Compaq touchscreen protocol output Adding 979956k swap on /dev/hda2. Priority:-1 extents:1 across:979956k device-mapper: ioctl: 4.7.0-ioctl (2006-06-24) initialised: dm-devel@redhat.com kjournald starting. Commit interval 5 seconds EXT3-fs warning: mounting fs with errors, running e2fsck is recommended EXT3 FS on hda4, internal journal EXT3-fs: mounted filesystem with ordered data mode. NET: Registered protocol family 10 lo: Disabled Privacy Extensions IPv6 over IPv4 tunneling driver eth0: link up, 100Mbps, full-duplex, lpa 0x45E1 usbcore: registered new driver usblp drivers/usb/class/usblp.c: v0.13: USB Printer Device Class driver eth0: no IPv6 routers present nvidia: module license 'NVIDIA' taints kernel. ACPI: PCI Interrupt 0000:01:00.0[A] -> GSI 16 (level, low) -> IRQ 201 NVRM: loading NVIDIA Linux x86 Kernel Module 1.0-8776 Mon Oct 16 21:56:04 PDT 2006 agpgart: Found an AGP 3.5 compliant device at 0000:00:00.0. agpgart: Putting AGP V3 device at 0000:00:00.0 into 8x mode agpgart: Putting AGP V3 device at 0000:01:00.0 into 8x mode usb 5-1: new high speed USB device using ehci_hcd and address 2 usb 5-1: configuration #1 chosen from 1 choice Initializing USB Mass Storage driver... scsi2 : SCSI emulation for USB Mass Storage devices usbcore: registered new driver usb-storage USB Mass Storage support registered. usb-storage: device found at 2 usb-storage: waiting for device to settle before scanning Vendor: JetFlash Model: TS4GJFV30 Rev: 0.00 Type: Direct-Access ANSI SCSI revision: 02 usb-storage: device scan complete SCSI device sda: 8060927 512-byte hdwr sectors (4127 MB) sda: Write Protect is off sda: Mode Sense: 00 00 00 00 sda: assuming drive cache: write through SCSI device sda: 8060927 512-byte hdwr sectors (4127 MB) sda: Write Protect is off sda: Mode Sense: 00 00 00 00 sda: assuming drive cache: write through sda: sda1 sd 2:0:0:0: Attached scsi removable disk sda

Désolé c’est un peu long… Mais on dirait bien que l’USB 2.0 ne pose pas de problème

Et pour les logs, voici ce que cela donne juste après la copie d’un fichier de 650Mo dans /var/log/syslog :

Jan 18 10:54:16 localhost kernel: usb 5-1: new high speed USB device using ehci_hcd and address 2 Jan 18 10:54:16 localhost kernel: usb 5-1: configuration #1 chosen from 1 choice Jan 18 10:54:16 localhost kernel: Initializing USB Mass Storage driver... Jan 18 10:54:16 localhost kernel: scsi2 : SCSI emulation for USB Mass Storage devices Jan 18 10:54:16 localhost kernel: usbcore: registered new driver usb-storage Jan 18 10:54:16 localhost kernel: USB Mass Storage support registered. Jan 18 10:54:16 localhost kernel: usb-storage: device found at 2 Jan 18 10:54:16 localhost kernel: usb-storage: waiting for device to settle before scanning Jan 18 10:54:21 localhost kernel: Vendor: JetFlash Model: TS4GJFV30 Rev: 0.00 Jan 18 10:54:21 localhost kernel: Type: Direct-Access ANSI SCSI revision: 02 Jan 18 10:54:21 localhost kernel: usb-storage: device scan complete Jan 18 10:54:21 localhost kernel: SCSI device sda: 8060927 512-byte hdwr sectors (4127 MB) Jan 18 10:54:21 localhost kernel: sda: Write Protect is off Jan 18 10:54:21 localhost kernel: sda: Mode Sense: 00 00 00 00 Jan 18 10:54:21 localhost kernel: sda: assuming drive cache: write through Jan 18 10:54:21 localhost kernel: SCSI device sda: 8060927 512-byte hdwr sectors (4127 MB) Jan 18 10:54:21 localhost kernel: sda: Write Protect is off Jan 18 10:54:21 localhost kernel: sda: Mode Sense: 00 00 00 00 Jan 18 10:54:21 localhost kernel: sda: assuming drive cache: write through Jan 18 10:54:21 localhost kernel: sda: sda1 Jan 18 10:54:21 localhost kernel: sd 2:0:0:0: Attached scsi removable disk sda Jan 18 11:00:09 localhost gconfd (root-4215): démarrage (version 2.16.0), pid 4215 utilisateur « root » Jan 18 11:00:09 localhost gconfd (root-4215): Adresse « xml:readonly:/etc/gconf/gconf.xml.mandatory » résolue vers une source de configuration en lecture seule à la position 0 Jan 18 11:00:09 localhost gconfd (root-4215): Adresse « xml:readwrite:/root/.gconf » résolue vers une source de configuration accessible en écriture à la position 1 Jan 18 11:00:09 localhost gconfd (root-4215): Adresse « xml:readonly:/etc/gconf/gconf.xml.defaults » résolue vers une source de configuration en lecture seule à la position 2 Jan 18 11:00:09 localhost gconfd (root-4215): Adresse « xml:readonly:/var/lib/gconf/debian.defaults » résolue vers une source de configuration en lecture seule à la position 3 Jan 18 11:00:09 localhost gconfd (root-4215): Adresse « xml:readonly:/var/lib/gconf/defaults » résolue vers une source de configuration en lecture seule à la position 4 Jan 18 11:01:09 localhost gconfd (root-4215): Le serveur GConf n'est pas en cours d'utilisation, arrêt. Jan 18 11:01:09 localhost gconfd (root-4215): Sortie Jan 18 11:03:23 localhost gconfd (root-4229): démarrage (version 2.16.0), pid 4229 utilisateur « root » Jan 18 11:03:23 localhost gconfd (root-4229): Adresse « xml:readonly:/etc/gconf/gconf.xml.mandatory » résolue vers une source de configuration en lecture seule à la position 0 Jan 18 11:03:23 localhost gconfd (root-4229): Adresse « xml:readwrite:/root/.gconf » résolue vers une source de configuration accessible en écriture à la position 1 Jan 18 11:03:23 localhost gconfd (root-4229): Adresse « xml:readonly:/etc/gconf/gconf.xml.defaults » résolue vers une source de configuration en lecture seule à la position 2 Jan 18 11:03:23 localhost gconfd (root-4229): Adresse « xml:readonly:/var/lib/gconf/debian.defaults » résolue vers une source de configuration en lecture seule à la position 3 Jan 18 11:03:23 localhost gconfd (root-4229): Adresse « xml:readonly:/var/lib/gconf/defaults » résolue vers une source de configuration en lecture seule à la position 4 Jan 18 11:05:23 localhost gconfd (root-4229): Le serveur GConf n'est pas en cours d'utilisation, arrêt. Jan 18 11:05:23 localhost gconfd (root-4229): Sortie Jan 18 11:06:12 localhost kernel: usb 5-1: USB disconnect, address 2 Jan 18 11:06:18 localhost gconfd (root-4264): démarrage (version 2.16.0), pid 4264 utilisateur « root » Jan 18 11:06:18 localhost gconfd (root-4264): Adresse « xml:readonly:/etc/gconf/gconf.xml.mandatory » résolue vers une source de configuration en lecture seule à la position 0 Jan 18 11:06:18 localhost gconfd (root-4264): Adresse « xml:readwrite:/root/.gconf » résolue vers une source de configuration accessible en écriture à la position 1 Jan 18 11:06:18 localhost gconfd (root-4264): Adresse « xml:readonly:/etc/gconf/gconf.xml.defaults » résolue vers une source de configuration en lecture seule à la position 2 Jan 18 11:06:18 localhost gconfd (root-4264): Adresse « xml:readonly:/var/lib/gconf/debian.defaults » résolue vers une source de configuration en lecture seule à la position 3 Jan 18 11:06:18 localhost gconfd (root-4264): Adresse « xml:readonly:/var/lib/gconf/defaults » résolue vers une source de configuration en lecture seule à la position 4

Voilà, désolé pour le gros pavé…
Et merci pour votre aide

Il y a plusieurs options de fonctionnement possible pour l’usb dans le noyau, dont certaines ayant un impact radical sur les perfs (justement sur la gestion du débit max autorisé, par exemple).
Il faudrait regarder les options interressantes avec un menuconfig, noter les flags auxquels elles correspondent dans le .config, et les tester on/off pour voir quelle config corrige le problême.