On Tue, Nov 05, 2024 at 12:47:27PM +0100, Toke Høiland-Jørgensen wrote: > Simon Horman <horms@xxxxxxxxxx> writes: > > > + Toke > > > > On Tue, Oct 29, 2024 at 06:36:56PM +0800, Qingfang Deng wrote: > >> When testing the parallel TX performance of a single PPPoE interface > >> over a 2.5GbE link with multiple hardware queues, the throughput could > >> not exceed 1.9Gbps, even with low CPU usage. > >> > >> This issue arises because the PPP interface is registered with a single > >> queue and a tx_queue_len of 3. This default behavior dates back to Linux > >> 2.3.13, which was suitable for slower serial ports. However, in modern > >> devices with multiple processors and hardware queues, this configuration > >> can lead to congestion. > >> > >> For PPPoE/PPTP, the lower interface should handle qdisc, so we need to > >> set IFF_NO_QUEUE. For PPP over a serial port, we don't benefit from a > >> qdisc with such a short TX queue, so handling TX queueing in the driver > >> and setting IFF_NO_QUEUE is more effective. > >> > >> With this change, PPPoE interfaces can now fully saturate a 2.5GbE link. > >> > >> Signed-off-by: Qingfang Deng <dqfext@xxxxxxxxx> > > > > Hi Toke, > > > > I'm wondering if you could offer an opinion on this. > > Hi Simon > > Thanks for bringing this to my attention; I'll reply to the parent > directly :) Likewise, thanks for following-up on this.
