svn commit: r327559 - in head: . sys/net

[Slawa Olhovchenkov]

On Fri, Jan 05, 2018 at 03:50:31AM +0700, Eugene Grosbein wrote:

> 05.01.2018 3:05, Steven Hartland wrote:
> 
> > Author: smh
> > Date: Thu Jan  4 20:05:47 2018
> > New Revision: 327559
> > URL: https://svnweb.freebsd.org/changeset/base/327559
> > 
> > Log:
> >   Disabled the use of flowid for lagg by default
> >   
> >   Disabled the use of RSS hash from the network card aka flowid for
> >   lagg(4) interfaces by default as it's currently incompatible with
> >   the lacp and loadbalance protocols.
> >   
> >   The incompatibility is due to the fact that the flowid isn't know
> >   for the first packet of a new outbound stream which can result in
> >   the hash calculation method changing and hence a stream being
> >   incorrectly split across multiple interfaces during normal
> >   operation.
> >   
> >   This can be re-enabled by setting the following in loader.conf:
> >   net.link.lagg.default_use_flowid="1"
> >   
> >   Discussed with: kmacy
> >   Sponsored by:	Multiplay
> 
> RSS by definition has meaning to received stream. What is "outbound" stream
> in this context, why can the hash calculatiom method change and what exactly
> does it mean "a stream being incorrectly split"?
> 
> Defaults should not be changed so easily just because they are not optimal
> for some specific case. Each lagg has its own setting for flowid usage
> and why one cannot just use "ifconfig lagg0 -use_flowid" for such cases?

Irrelevant to RSS and etc. flowid distribution in lacp case work very
bad. This is good and must be MFC (IMHO).