On 15 Feb 2004 at 19:30, Fabrizio Diversi wrote:

> I have a lot of different configurations, but the only 10 Mb card I
> have is used into the Q60 and Q40. I have to think about how to
> arrange it. BTW 854 kb/sec I think is near the maximum you can reach
> (10% less than the nominal value of 1000) and is far from what i
> thought was possible to obtain with QLwIP . Good results, according
> the fact that you told us QLwIP was slow ......

A bit of misunderstanding I guess. QLwIP with polled ethernet driver never 
was slow by itself, but I deliberately reduced speed, because for some 
(yet unknown) reason, a massive usage of scheduler calls under QDOS (and 
SMSQ/E likewise) could make a job stay suspended although there had been a 
release call. It is yet unclear wether this is a problem of QLwIP or the 
OS. Neither QDOS nor SMSQ/E have ever been tested with something like 
10000 scheduler calls per second, from several different jobs, partially 
triggered by asynchronous events. So I have no reference.

What you might be referring to, is the principal shortcoming of QDOS if an 
ISR-driven structure is used. With such a clean driver, _every_ 
multitasking TCP implementation that uses jobs for the higher protocol 
levels is indeed doomed to a limited throughput, i.e. "slow".

So the figure of 854 kB/sec stems from a polled driver. I've been able to 
reduce the amount of scheduler calls at the cost of some more polling. 
This version is still experimental and not 100% stable.

I'm not sure if 854 kB/sec is a good result. BTW I only get this if the 
file is already buffered. Otherwise the efficiency of harddisk plus driver 
(or the lack thereof) is measured.

All the best

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