Bruce Evans wrote:
> On Thu, 7 Sep 2000, Warner Losh wrote:
> > In message <[EMAIL PROTECTED]> The Hermit
> > : sio1: 32 more interrupt-level buffer overflows (total 32)
> > >From the man page:
> > sio%d: interrupt-level buffer overflow. Problem in the bottom half of
> > the driver.
> > This likely means that the bottom half of sio isn't running fast
> > enough to harvest the characters in the interrupt level buffers.
> This means that fast interrupt handlers aren't actually fast. Especially
> if it occurs for slow devices like mouses. Even slow interrupt handlers
> had about 10 times lower latency than necessary for 1200 bps serial mouses.
Well unfortunately this doesn't make sense since the sio interrupt _is_ still
fast, and thus is not run as a thread as other interrupts, but is run just
like old fast interrupts were. However, there is an issue with sio right
now in that it's not getting any input (actually, on my test machines, I
can't get the stupid hardware to set the actual DCD bit, so I can't even
open the devices *sigh*). My guess then is that we aren't scheduling the
soft interrupt to harvest the data in the top half from the bottom half.
John Baldwin <[EMAIL PROTECTED]> -- http://www.FreeBSD.org/~jhb/
PGP Key: http://www.cslab.vt.edu/~jobaldwi/pgpkey.asc
"Power Users Use the Power to Serve!" - http://www.FreeBSD.org/
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