Subject: Re: /netbsd: ser0: silo overflow
To: None <port-amiga@netbsd.org>
From: Georges Heinesch <geohei-ml@geohei.lu>
List: port-amiga
Date: 05/02/2001 23:40:29
Quoting Ignatios Souvatzis (29-Apr-01 20:18:52):

> On Sun, Apr 29, 2001 at 05:05:57PM +0100, Georges Heinesch wrote:

>> Done!
>> 
>> Test 1:
>> 
>>     #options    SERIBUF_SIZE=4046
>>     #options    LEV6_DEFER
>> 
>>     I added 'deflate 15,15' and 'bsdcomp 15,15' to
>>     '/etc/ppp/options.tty00'. No result.
>> 
>>     Provider 1 - lynx download (pkgsrc) - +50 silo errors
>>     Provider 2 - gimp download (pkgsrc) - +80 silo errors
>> 
>> >From now on, 'deflate' and 'bsdcomp' were commented out.

> The idea is to have deflate and/or bsdcomp AND to reduce the serial
> in/out speed (between modem and computer) to the absolute minimum
> that  keeps the modem busy, so as to maximize the guaranteed minimum
> of time between interupts. bsdcomp/deflate ONLY won't help, as it
> only reduces the average interupt frequency needed, but does not
> influence the minimum time available between interupts.

Tested now.

    'deflate 15,15'
    'bsdcomp 15,15'
    options    SERIBUF_SIZE=1000000 /* one million !!! */
    options    LEV6_DEFER

    -> no change! many errors!

    Is it possible to fine tune the serial driver a bit?

> Those errors don't corrupt data, but they cause a resend of a packet
> at the TCP level, which reduces overall tcp throughput.

Ok, thanks.

-- 
Cu  Georges Heinesch, Luxembourg
    geohei@geohei.lu
    http://www.geohei.lu
    PGP RSA & DH/DSS public key on request and on public servers

... don't do anything, I wouldn't do ...