RE: [PATCH V2,net] net: mana: Fix perf regression: remove rx_cqes, tx_cqes counters

[Haiyang Zhang]

> -----Original Message-----
> From: Jakub Kicinski <kuba@xxxxxxxxxx>
> Sent: Thursday, May 25, 2023 11:26 PM
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> Subject: Re: [PATCH V2,net] net: mana: Fix perf regression: remove rx_cqes,
> tx_cqes counters
> 
> On Thu, 25 May 2023 07:46:30 -0700 Haiyang Zhang wrote:
> > lot caching and memory overhead, hence perf regression.
> 
> Horatiu's ask for more details was perfectly reasonable.
> Provide more details to give the distros and users an
> idea of the order of magnitude of the problem. Example
> workload and relative perf hit, anything.

For example, a workload is iperf with 128 threads, and with RPS enabled.
We saw perf regression of 25% with the previous patch adding the counters.
And this patch eliminates the regression. 

Thanks,
- Haiyang