Subject: Re: usb 2.0 umass unusably slow?
To: None <email@example.com>
From: Ben Harris <firstname.lastname@example.org>
Date: 06/23/2003 17:13:43
In article <email@example.com> you write:
>Are there any known issues with the umass driver that
>makes things _extremely_ ( < 300kb/sec) slow for this
>USB 2.0 hard drive below? Perhaps this needs some
>sort of quirk entry in umass_quirks.c?
How are you testing the speed? With my USB hard disk, when doing simple
tests with dd on the raw device, I seem to get speeds that vary almost
linearly with block size until I hit MAXPHYS:
viking:/home/bjh21# dd if=/dev/rsd2c of=/dev/null bs=1k count=1024
1048576 bytes transferred in 30.827 secs (34014 bytes/sec)
viking:/home/bjh21# dd if=/dev/rsd2c of=/dev/null bs=8k count=1024
8388608 bytes transferred in 32.282 secs (259854 bytes/sec)
viking:/home/bjh21# dd if=/dev/rsd2c of=/dev/null bs=32k count=1024
33554432 bytes transferred in 32.206 secs (1041868 bytes/sec)
viking:/home/bjh21# dd if=/dev/rsd2c of=/dev/null bs=64k count=1024
67108864 bytes transferred in 31.139 secs (2155138 bytes/sec)
viking:/home/bjh21# dd if=/dev/rsd2c of=/dev/null bs=128k count=1024
134217728 bytes transferred in 63.318 secs (2119740 bytes/sec)
I'm not sure if this indicates an actual problem, or just an enormous
per-command overhead on USB.
> port 2 addr 2: full speed, self powered, config 1,USB 2.0 Hard Drive(0x2507),
>BUSlink(0x0caf), rev 0.01
"full speed" is USB 1, 12 Mbit/s, so you can't expect to get all that much
performance out of it.
FWIW, here's mine:
umass0 at uhub2 port 4 configuration 2 interface 0
umass0: Maxtor Maxtor USB Drive, rev 2.00/11.01, addr 2
umass0: using SCSI over Bulk-Only
scsibus2 at umass0: 2 targets, 1 luns per target
scsibus2: waiting 2 seconds for devices to settle...
sd2 at scsibus2 target 1 lun 0: <Maxtor 4, D040H2, DAK0> SCSI0 0/direct fixed
sd2: could not mode sense (4/5); using fictitious geometry
sd2: 39083 MB, 39083 cyl, 64 head, 32 sec, 512 bytes/sect x 80043264 sectors
viking:/home/bjh21# usbdevs -vf /dev/usb2
addr 1: high speed, self powered, config 1, EHCI root hub(0x0000), NEC(0x1033), rev 1.00
port 1 powered
port 2 powered
port 3 powered
port 4 addr 2: high speed, self powered, config 2, Maxtor USB Drive(0x3000), Maxtor(0x0d49), rev 11.01
port 5 powered
Note "high speed".
Ben Harris <firstname.lastname@example.org>
Portmaster, NetBSD/acorn26 <URL:http://www.netbsd.org/Ports/acorn26/>