Hi all,
I'm sorry, I'm not sure that I can take part in tomorrow meeting, so,
I'd like to drop my thoughts on the topic via E-mail.
Existing "meter" object which pulls profile and policy together allows
do apply metering in one flow-based lookup for different flows.
I.e. we can route absolutely different flows to one meter object to
share metering counters. When we know meter ID for a flow, everything
becomes simple - just get corresponding metering counters, apply it and
do actions based on color. Yes, it is not flexible, but very simple. As
I understand the configuration model enforces to define actions for all
colors.
A new model, if I'm not mistaken, will require three flow-based lookups:
1. To assign a TAG based on flow fields (to handle different flows in
one meter)
2. To do metering for packets with a TAG
3. To find actions based on color
Of course, (2) and (3) are done in existing model with meter ID, but
here it is a generic flow-based lookups with extra matching criteria.
Yes, it is true that it gives extra flexibility, but everything has its
price.
Theoretically old model could be expressed using new one (and,
therefore, supported on old HW), but it is a bit tricky and raises many
questions on how to handle it correctly in all cases. E.g. if a TAG is
the only pattern in non-zero table and used for meter+jump actions only,
it could be associated with meter ID.
Above jump table specified after meter action could be associated with a
policy ID. If action for a color is not specified in a table, it should
be drop by default.
Indirect actions or action templates could help to do meter profile job
- define profile in single place.
To sum up, since some HW could support the flexibility provided by
suggested flow API items/actions. I see no reason to block it. Solution
looks good from flow API design point of view.
May be I'm missing something since I'm not expert in QoS and have no
hands-on experience with meters in DPDK.
Andrew.
