> But Juergen is correct of course, try to see first what your interface 
> gives you when reading / writing "raw". That's the benchmark, you can't 
> expect pcfs to beat these numbers - and if they're too low, the first 
> thing to address is why the device doesn't do USB 2 (though it should ?).

According to Bruno' reply...

   http://www.opensolaris.org/jive/thread.jspa?messageID=223135#222849

... the usb storage device is connect to an usb 2.0 hub, and does seem
to use usb 2.0 protocol.

The box has 4GB of physical ram, so a part of it should be remapped to
physical addresses >= 4GB, and (AFAIR) the ehci driver does not yet
support DMA to addresses >= 4GB.  So ehci might be blocked waiting for
DMA resources / memory below 4GB...


> 
> 
> FrankH.
> 
> >
> >
> > Bruno: is both reading from and writing to the USB
> drive slow?
> >
> > How much physical memory do you have installed in
> the machine?
> >
> > Try to read 100mbytes directly from the raw usb
> storage device,
> > using different block sizes;  how long does it
> take?
> >
> > # ptime dd if=/dev/rdsk/c6t0d0p0 of=/dev/null bs=8k
> count=12800
> > 12800+0 records in
> > 12800+0 records out
> >
> > real       14.449
> > user        0.039
> > sys         0.345
> >
> >
> > # ptime dd if=/dev/rdsk/c6t0d0p0 of=/dev/null
> bs=32k count=3200
> > 3200+0 records in
> > 3200+0 records out
> >
> > real       11.531
> > user        0.010
> > sys         0.141
> >
> >
> > # ptime dd if=/dev/rdsk/c6t0d0p0 of=/dev/null
> bs=256k count=400
> > 400+0 records in
> > 400+0 records out
> >
> > real       10.706
> > user        0.002
> > sys         0.085
> >
> >
> > This message posted from opensolaris.org
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> >
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