Re: /netbsd: ser0: silo overflow

["Georges Heinesch" <geohei-ml%geohei.lu@localhost>]

Quoting John (04-May-01 16:46:14):

>> >>     'deflate 15,15'
>> >>     'bsdcomp 15,15'
>> >>     options    SERIBUF_SIZE=1000000 /* one million !!! */
>> >>     options    LEV6_DEFER
>> >>
>> >>     -> no change! many errors!
>>
>> > a) what bitrate?
>>
>> Quite normal, between 3.5 and 5.1 KB/s

> Forgive me if I haven't followed along very closely, but let me
> relate my problems and tell you what I thought Ignatios was saying.

> First, to be absolutely honest, an A3000 won't do 57600 baud
> reliably. The buffer is too small, and the interrupts don't happen
> quickly enough. In AmigaOS, things are a bit more lean, so you can
> usually do 57600.

Ok.

> So one of the fixes relies on the fact that modems generally
> compress; this is why, with a fast serial port, you'd configure the
> speed between the computer and the modem to be 115200 baud even if
> the modem is a 33k or a 56k. Compressed text over 33k can easily
> exceed the speed of a serial port running at 57600 baud.

Understandable.

> So rather than allowing the modem to do compression, Ignatios
> suggested you turn on ppp compression in software

Done with "deflate 15,15" and "bsdcomp 15,15"

> and run the serial
> port at 38400 baud. This way, the serial port of the Amiga, which is
> the weakest link, will be transmitting slower but compressed data
> instead of faster but uncompressed data, hence less errors.

Yep. However even with 38400 baud, I got silo errors.

I was not aware that 57600 would create such problems, since I use to
run my A3000 with the 8n1.device and 115200 without any problem for
ages. Also the internal MiamiDx serial driver never complains about
the selected 57600 (or, if I think about it ... he might complain, but
I don't see it).

Therefore I was quite surprized to see these "silo overflow" errors
all of a sudden.

I let it run now with 57600 and silo errors.
Ignatios said it's acceptable ;)

> Forgive me if I'm confusing this thread with another that was here
> recently, but it's all the same from Ignatios - good info worth
> repeating.

Right. You didn't confuse at all, you clarified further down.

Thanks!

-- 
Cu  Georges Heinesch, Luxembourg
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