RE: [PATCH V3,net-next] net: mana: Add page pool for RX buffers

From: Haiyang Zhang
Date: Wed Jul 26 2023 - 11:51:51 EST




> -----Original Message-----
> From: Jesper Dangaard Brouer <jbrouer@xxxxxxxxxx>
> Sent: Wednesday, July 26, 2023 5:23 AM
> >
> > In mana_gd_setup_irqs(), we set the default IRQ/CPU affinity to gc-
> >numa_node
> > too, so it won't revert the nid initial setting.
> >
> > Currently, the Azure hypervisor always indicates numa 0 as default. (In
> > the future, it will start to provide the accurate default dev node.) When a
> > user manually changes the IRQ/CPU affinity for perf tuning, we want to
> > allow page_pool_nid_changed() to update the pool. Is this OK?
> >
>
> If I were you, I would wait with the page_pool_nid_changed()
> "optimization" and do a benchmark mark to see if this actually have a
> benefit. (You can do this in another patch). (In a Azure hypervisor
> environment is might not be the right choice).
Ok, I will submit a patch without the page_pool_nid_changed() optimization
for now, and will do more testing on this.

> This reminds me, do you have any benchmark data on the improvement this
> patch (using page_pool) gave?
With iperf and 128 threads test, this patch improved the throughput by 12-15%,
and decreased the IRQ associated CPU's usage from 99-100% to 10-50%.

Thanks,
- Haiyang