Greetings,

I tested with the hdparm with two pen drives, one USB 2.0 and one USB
1.1 on a board with support for USB 2.0. I'm using kernel 2.4.20 and I'm
also using the USB 2.0 EHCI (experimental).

This are my results:

hdparm -t /dev/sdb1 (USB 1.1)

/dev/sdb1:
 Timing buffered disk reads:  64 MB in 67.67 seconds =968.46 kB/sec

hdparm -t /dev/sda1 (USB 2.0)

/dev/sda1:
  Timing buffered disk reads:  64 MB in 13.62 seconds =  4.70 MB/sec

However this results are very far (specially in the USB 2.0 device) from
the limits announced in the USB:

USB 2.0 ~ high speed, at 480 Mbit/sec
USB 1.1 ~ low speed at 1.5 Mbit/sec, and full speed at 12 Mbit/sec

Is my system under the right conditions to get the full power of USB
(1.1 or 2.0), or there are some limitations/bottlenecks beyond the limit
of the values announced in theory?

thanks,
Pedro Salazar.

P.S.- I put below the output of /proc/bys/usb/devices

T:  Bus=04 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480 MxCh= 6
B:  Alloc=  0/800 us ( 0%), #Int=  1, #Iso=  0
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS= 8 #Cfgs=  1
P:  Vendor=0000 ProdID=0000 Rev= 2.04
S:  Manufacturer=Linux 2.4.20 ehci-hcd
S:  Product=PCI device 1039:7002 (Silicon Integrated Systems [SiS])
S:  SerialNumber=00:03.3
C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr=  0mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   2 Ivl=256ms
T:  Bus=04 Lev=01 Prnt=01 Port=05 Cnt=01 Dev#=  2 Spd=480 MxCh= 1
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=054c ProdID=0105 Rev= 0.01
S:  Manufacturer=Sony
S:  Product=USB Embedded Hub
C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=100mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   1 Ivl=256ms
T:  Bus=04 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#=  3 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=054c ProdID=008b Rev= 0.01
S:  Manufacturer=Sony
S:  Product=USB Mass Storage Device
C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=  0mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=05 Prot=50
Driver=usb-storage
E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
T:  Bus=03 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=12  MxCh= 2
B:  Alloc=  0/900 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 1.10 Cls=09(hub  ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
P:  Vendor=0000 ProdID=0000 Rev= 0.00
S:  Product=USB OHCI Root Hub
S:  SerialNumber=de82c000
C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr=  0mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   2 Ivl=255ms
T:  Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=12  MxCh= 2
B:  Alloc=  0/900 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 1.10 Cls=09(hub  ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
P:  Vendor=0000 ProdID=0000 Rev= 0.00
S:  Product=USB OHCI Root Hub
S:  SerialNumber=de82a000
C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr=  0mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   2 Ivl=255ms
T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=12  MxCh= 2
B:  Alloc=  0/900 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 1.10 Cls=09(hub  ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
P:  Vendor=0000 ProdID=0000 Rev= 0.00
S:  Product=USB OHCI Root Hub
S:  SerialNumber=de828000
C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr=  0mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   2 Ivl=255ms
T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  2 Spd=12  MxCh= 0
D:  Ver= 1.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
P:  Vendor=0ed1 ProdID=6680 Rev= 1.00
S:  Manufacturer=Generic
S:  Product=Mass Storage Device
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr= 50mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50
Driver=usb-storage
E:  Ad=01(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
E:  Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms

-- 
PS
[EMAIL PROTECTED]
PGP:0E129E31D803BC61



-------------------------------------------------------
This SF.NET email is sponsored by: eBay
Great deals on office technology -- on eBay now! Click here:
http://adfarm.mediaplex.com/ad/ck/711-11697-6916-5
_______________________________________________
[EMAIL PROTECTED]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-users

Reply via email to