* [9fans] usb ohci testing
@ 2011-09-01 10:11 Richard Miller
2011-09-01 16:25 ` cinap_lenrek
2011-09-01 16:47 ` cinap_lenrek
0 siblings, 2 replies; 13+ messages in thread
From: Richard Miller @ 2011-09-01 10:11 UTC (permalink / raw)
To: 9fans
I have a small experimental change to /sys/src/9/pc/usbohci.c which
is needed to get my macbook's built-in bluetooth working with Plan 9
under virtualbox. As a pleasing side effect, it speeds up reading of
usb1.0 flash disks by about a factor of ten.
Before submitting a patch I want to check that it also works on native
Plan 9, but I don't have suitable hardware. Would someone running
native Plan 9 on a motherboard with an ohci host adapter like to help,
by building a kernel with the usbohci.c from /n/sources/contrib/miller,
testing that any usb1.0 devices still work, and measuring usb disk speed
before and after with something like:
time dd -if /dev/sdU0.0/data -of /dev/null -bs 64k -count 16
Note that usb2.0 devices should not be affected by the change, because
they will be handled by the usbehci.c driver. You can use usb/probe
to check which usb driver (uhci, ohci, ehci) is handling each plugged-in
device.
In theory you can force usb2.0 devices to be handled by ohci as well,
by setting *nousbehci=1 in plan9.ini to disable the ehci driver. This
doesn't work for me on virtualbox (which gets thoroughly wedged when I
attach a usb2.0 flash drive), but it might work on real hardware.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [9fans] usb ohci testing
2011-09-01 10:11 [9fans] usb ohci testing Richard Miller
@ 2011-09-01 16:25 ` cinap_lenrek
2011-09-01 16:40 ` erik quanstrom
2011-09-01 16:42 ` cinap_lenrek
2011-09-01 16:47 ` cinap_lenrek
1 sibling, 2 replies; 13+ messages in thread
From: cinap_lenrek @ 2011-09-01 16:25 UTC (permalink / raw)
To: 9fans
will try as soon as possible.
as far as i can see that patch limits the packet size for
the transfers to 8K no?
any insights on why this has such an dramatic impact on
performance?
--
cinap
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [9fans] usb ohci testing
2011-09-01 16:25 ` cinap_lenrek
@ 2011-09-01 16:40 ` erik quanstrom
2011-09-01 16:42 ` cinap_lenrek
1 sibling, 0 replies; 13+ messages in thread
From: erik quanstrom @ 2011-09-01 16:40 UTC (permalink / raw)
To: cinap_lenrek, 9fans
On Thu Sep 1 12:27:31 EDT 2011, cinap_lenrek@gmx.de wrote:
> will try as soon as possible.
>
> as far as i can see that patch limits the packet size for
> the transfers to 8K no?
since each frame is 1ms, it would take a 64Mbit line rate
to deliver 8k/frame. since by definition we're talking about
usb1.1, i don't see how you could get >8k/frame.
actually, i'm not sure how we could get over 4k/frame since
32Mbit >> 12Mbit.
> any insights on why this has such an dramatic impact on
> performance?
paging in a virtual environment is teh suck without hardware assist.
- erik
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [9fans] usb ohci testing
2011-09-01 16:25 ` cinap_lenrek
2011-09-01 16:40 ` erik quanstrom
@ 2011-09-01 16:42 ` cinap_lenrek
1 sibling, 0 replies; 13+ messages in thread
From: cinap_lenrek @ 2011-09-01 16:42 UTC (permalink / raw)
To: 9fans
> as far as i can see that patch limits the packet size for
> the transfers to 8K no?
correction, that was WRONG...
--
cinap
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [9fans] usb ohci testing
2011-09-01 10:11 [9fans] usb ohci testing Richard Miller
2011-09-01 16:25 ` cinap_lenrek
@ 2011-09-01 16:47 ` cinap_lenrek
2011-09-01 16:55 ` Richard Miller
1 sibling, 1 reply; 13+ messages in thread
From: cinap_lenrek @ 2011-09-01 16:47 UTC (permalink / raw)
To: 9fans
0.00u 0.00s 0.39r
--
cinap
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2011-09-02 8:51 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-09-01 10:11 [9fans] usb ohci testing Richard Miller
2011-09-01 16:25 ` cinap_lenrek
2011-09-01 16:40 ` erik quanstrom
2011-09-01 16:42 ` cinap_lenrek
2011-09-01 16:47 ` cinap_lenrek
2011-09-01 16:55 ` Richard Miller
2011-09-01 17:23 ` cinap_lenrek
2011-09-01 17:55 ` Richard Miller
2011-09-01 18:22 ` cinap_lenrek
2011-09-01 18:50 ` Richard Miller
2011-09-02 5:06 ` erik quanstrom
2011-09-02 8:48 ` cinap_lenrek
2011-09-02 8:51 ` Richard Miller
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