[ofa-general] QoS RFC

[Or Gerlitz]

Sean Hefty wrote:
>> 2. Architecture ----------------
> 
> This is a higher level approach to the problem, but I came up with the
> following QoS relationship hierarchy, where '->' means 'maps to'.
> 
> Application Service -> Service ID (or range)
> Service ID -> desired QoS
> QoS, SGID, DGID, PKey -> SGID, DGID, TClass, FlowLabel, PKey
> SGID, DGID, TC, FL, PKey -> SLID, DLID, SL (set if crossing subnets)
> SLID, DLID, SL -> MTU, Rate, VL, PacketLifeTime

What's the reasoning to use TClass and Flowlabel here? is it that you 
want to come up with a scheme which is valid also for traffic crossing 
IB subnets?

you suggest two mappings:

A) from SID to "desired QoS"
B) from "desired QoS" (and more params) to TClass and FlowLabel

First, my understanding is that "QoS" is an abstract term here, that is 
does not translate to concrete IB term, correct? now, what entity per 
your design would translate from SID to QoS, is it something done 
internally in the host stack similar to what the net stack does with the 
IP_TOS and SOL_PRIORITY socket options?

Or.