[dpdk-dev] [RFC PATCH 0/3] Add PIE support for HQoS library

[Morten Brørup]

> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Liguzinski,
> WojciechX
> Sent: Monday, 24 May 2021 12.58
> 
> DPDK sched library is equipped with mechanism that secures it from the
> bufferbloat problem
> which is a situation when excess buffers in the network cause high
> latency and latency
> variation. Currently, it supports RED for queue congestion control

The correct term is "active queue management", not "queue congestion control".

> (which is designed
> to control the queue length but it does not control latency directly
> and is now being
> obsoleted ).

Some might prefer other algorithms, such as PIE, CoDel, CAKE, etc., but RED is not obsolete!

> However, more advanced queue management is required to
> address this problem
> and provide desirable quality of service to users.
> 
> This solution (RFC) proposes usage of new algorithm called "PIE"
> (Proportional Integral
> controller Enhanced) that can effectively and directly control queuing
> latency to address
> the bufferbloat problem.
> 
> The implementation of mentioned functionality includes modification of
> existing and
> adding a new set of data structures to the library, adding PIE related
> APIs.
> This affects structures in public API/ABI. That is why deprecation
> notice is going
> to be prepared and sent.
> 
> 
> Liguzinski, WojciechX (3):
>   sched: add pie based congestion management
>   example/qos_sched: add pie support
>   example/ip_pipeline: add pie support

It's "PIE", not "pie". :-)

Nonetheless, the RFC looks good!

-Morten