On Sun, Sep 09, 2001 at 02:08:16AM +0100, Lars Hecking wrote:
> 
>  Amiga 3000, CS MkIII, builtin serial port.
> 
>  PPP networking under 1.5.1 sucks massively. I have
> 
> options         SERIBUF_SIZE=4096
> options         SEROBUF_SIZE=512
> options         LEV6_DEFER      # defers l6 to l4 (below serial l5)
> 
>  in my kernel config file, and still I get TONS of ser0 silo overflow
>  messages. In addition, the connection often seems to go to sleep for
>  any amount of time. I often have to wait like 30s for a simple text
>  screen refresh. If there is any load on my NetBSD box, the connection
>  appears to blackout completely, until the load goes down.
> 
>  I would really appreciate some hints on how to tackle this.

The symptoms might point to broken serial handshaking. This can be any one of:

- broken serial cable at your end
- modem not notified of hardware handshaking at your end
- pppd not notified of hardware handshaking at your end ("crtscts" option)

- broken serial cable at provider
- modem not notified of hardware handshaking at provider
- pppd not notified of hardware handshaking at provider ("crtscts" option)

Nowadays, with less hobbyist dialup servers, the 2nd three seem less likely, 
especially as commercially-used hardware does operate on E1 and up digital
lines, doing ADC/DAC, modem function, "serial" handshaking, and PPP all-in-one.

And, of course, working pppd does NOT help when the serial line kernel driver
is broken.

This said: you should verify, using a serial line analyzer (err, one of those
7red+7green boxen you plug into the Amiga serial port then plugging the modem
cable into the other end) that the handshaking does work _right at the
Amiga_. Then you should do the same _right at the modem_, however here you
can look at the modem LEDs in most cases.

In both cases, when you do a bulk FTP upload, CTS should go 
off sometimes, and _at the same times_ TxD should be quiet; similarly,
if you do an FTP download, RTS shoudl go off sometimes, and RxD should
be quiet at the same time.

If this does not happen exactly as described above, please report what
_exactly_ happens! also, your full pppd configuration (excluding passwords
of course) and /etc/ttys and kernel startup messages (/var/run/dmesg.boot)
will be needed, and your full kernel configuration file.

Sorry if this is more explicit than you need, but I wanted to write the text
once and make a "pppd performance troubleshooting guide" out of it without
rewriting.

Regards,
	Ignatios