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: Friday, May 26, 2023 11:28 AM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Cc: linux-hyperv@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Dexuan Cui
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> Subject: Re: [PATCH V2,net] net: mana: Fix perf regression: remove rx_cqes,
> tx_cqes counters
> 
> On Fri, 26 May 2023 14:42:07 +0000 Haiyang Zhang wrote:
> > > 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.
> 
> Exactly what I was looking for, thanks. Please put that in the commit
> message and post v3 (feel free to add the review tags which came in for
> v1 in the meantime).

Will do.

Thanks!