Re: stable kernel, when?

Ralf Baechle (ralf@Julia.DE)
Wed, 29 Jan 1997 00:40:17 +0100 (MET)

> > > your firewall code which works as you say. The problem I've mentioned
> > > seem to be related to the packet logging feature (CONFIG_IP_FIREWALL_VERBOSE)
> > > of the firewall. When I flood ping an address for which packets will
> > > be logged via syslog the machine crashes. And you won't call the
> > > packet logging via printk & syslog hyper optimized, don't you?
> >
> > Its quite fast (or would be) but syslog writes to the log synchronously.
> > Its one of those things 2.1.x has fixed 8)
> Newer syslogd's let you disable the fsync call on a per logfile basis, so
> that writing lots of log info doesn't have to be a kick in the balls for
> your disk and i/o performance.

Well, not a new syslogd but with the the sync stuff removed. I don't mind
loosing just some bytes of syslog in case of a crash.

My personal next approach would be to make the kernel write the unformatted
log data (faster & more compact than ASCII) into a kernel circular buffer.
Add some special stuff for special cases like dropped packets. The
option to use speparate files for each matching logging entry in firewall.
Handy if you have to write bills based on that material.

Real solution: custumers should realize that IP by volume is a good bit
more expensive ... They want it anyway and we have to collect that
data for billing :-(