On Wed, 2006-09-13 at 15:03, Michael S. Tsirkin wrote: > Quoting r. Fabian Tillier <[EMAIL PROTECTED]>: > > Subject: Re: [PATCH for-2.6.18] IB/cma: option to limitMTU to 1K > > > > On 9/13/06, Michael S. Tsirkin <[EMAIL PROTECTED]> wrote: > > > Quoting r. Hal Rosenstock <[EMAIL PROTECTED]>: > > > > Subject: Re: [openib-general] [PATCH for-2.6.18] IB/cma: option to > > > > limitMTU to 1K > > > > > > > > On Wed, 2006-09-13 at 11:57, Michael S. Tsirkin wrote: > > > > > Tavor systems get better performance with 1K MTU. Since there does > > > > > not seem to be any way to find out whether the remote system uses > > > > > Tavor, > > > > > add an option to limit the MTU globally. > > > > > > > > Can't Tavor be determined locally ? > > > > > > It can, but we need this for remote tavor as well, anyway. > > > > > > > And couldn't the remote end negotiate the MTU down (if Tavor) as well ? > > > > > > The way to do this is would be for SA to select 1K MTU if it detects > > > Tavor on one side > > > and if this does not conflict with MTU selector. > > > > You can't do this because the SA doesn't have a way to tell if a path > > query is going to be used for RC or UD, and IPoIB needs paths with 2K > > MTU. > > I think we can do that without breaking IPoIB. > IPoIB needs mtu >= 1K.
Huh ? > IPoIB sets mtu selector to >= 2K. I don't think that's a requirement for IPoIB. > I am talking about users that do not set mtu selector. Understood. -- Hal _______________________________________________ openib-general mailing list openib-general@openib.org http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general