[vortex] 3c905CX-TXM

Richard Gooch rgooch@ras.ucalgary.ca
Thu, 23 Nov 2000 21:53:44 -0700


Andrew Morton writes:
> Richard Gooch wrote:
> > 
> > > I note that 3com's 3c90x.c busywaits for up to one second waiting
> > > for the command to complete.  So as an experiment I've asked Richard
> > > to increase the loop count to 4,000,000.
> > 
> > Which fixes the problem. Everything seems fine now. Throughput is over
> > 11 MB/s, as expected.
> 
> Ug.  How diabolical.
> 
> Thanks, Richard.  If it's OK I'll whip up a debug patch which we can
> use to find out which commands are taking how long and when.

OK. Oh, and I forgot in my last message: thanks for coming up with a
fix.

BTW: is there any way to make these waits non-busy? This is just
another thing that will screw over scheduling latency. If not, people
who care about latency will be avoiding 3Com cards...

				Regards,

					Richard....
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