[ofa-general] Re: [PATCH] opensm: preserve base lid routes

[Hal Rosenstock]

On Tue, 2008-06-10 at 05:59 +0300, Sasha Khapyorsky wrote:
> Basically this addresses the problem described by Al Chu in:
> 
> http://lists.openfabrics.org/pipermail/general/2008-April/049132.html
> 
> When base lid paths become completely disbalanced on a fabrics with
> lmc > 0.
> 
> One feedback was from Yiftah Shahar:
> 
> "I think that our requirements should be that even when you are working
> with LMC>0 then the base LID routing should not be affected.

> One way to achieve this goal is to first run the base-LID routing (so
> all base LID improvement will be also in LMC>0) and then start with the
> other LIDs as round-robbing starting from the base-lid-port + 1
> according current routing algorithm rules (keeping min-hop, up/down...)."
> 
> We had some discussion with Al and Yiftah about this and considered that
> in addition to "pure" base lid paths preservation (which is good thing by
> itself) proposed method solves original lid disbalancing problem as well.

Would you elaborate on the motivation behind the requirement to
maintain/preserve the base LID routing ?

-- Hal