Performance issues

[M. Warner Losh]

In message: <200908091840.55000.hselasky at c2i.net>
            Hans Petter Selasky <hselasky at c2i.net> writes:
: On Sunday 09 August 2009 18:23:41 M. Warner Losh wrote:
: > Any ideas how to track this down?
: 
: Hi,
: 
: USB is only draining from "usbd_transfer_drain()" in 
: /sys/dev/usb/usb_transfer.c . You could add a print including the backtrace 
: and see if that function gets called when it freezes.

Ummm.  No.  Adding a traceback print to a function that's called 60
times a second in steady state doesn't seem like a viable option.

: Else I would try to compile a fresh kernel from USB P4. There are
: some patches there in relation to the recent newbus lock change,
: that might help.

This kernel predates the newbus lock change.

: USB uses uppercase "WDRAIN". Is your printout lowercase "wdrain" ?

Yes.

Warner