RE: [PATCH] net/i40e: reduce the ITR interval of multi-driver mode

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Kevin Traynor <ktraynor@redhat.com>
> Sent: Thursday, February 23, 2023 12:49 AM
> To: Zhang, Qi Z <qi.z.zhang@intel.com>; Yang, Qiming
> <qiming.yang@intel.com>; dev@dpdk.org; Xing, Beilei
> <beilei.xing@intel.com>; Xueming(Steven) Li <xuemingl@nvidia.com>; Luca
> Boccassi <bluca@debian.org>
> Subject: Re: [PATCH] net/i40e: reduce the ITR interval of multi-driver mode
> 
> On 26/12/2022 05:50, Zhang, Qi Z wrote:
> >
> >
> >> -----Original Message-----
> >> From: Qiming Yang <qiming.yang@intel.com>
> >> Sent: Friday, December 16, 2022 11:12 AM
> >> To: dev@dpdk.org; Xing, Beilei <beilei.xing@intel.com>
> >> Cc: Yang, Qiming <qiming.yang@intel.com>
> >> Subject: [PATCH] net/i40e: reduce the ITR interval of multi-driver
> >> mode
> >>
> >> This patch change the interrupt interval from 8160us to 32us to
> >> improve the performance of multi-driver mode.
> >>
> >> Signed-off-by: Qiming Yang <qiming.yang@intel.com>
> >
> > Acked-by: Qi Zhang <qi.z.zhang@intel.com>
> >
> > Applied to dpdk-next-net-intel.
> >
> > The patch also looks good for backporting, so added Cc stable tag.
> >
> 
> Hi. This looks like it is not fixing anything and it is changing a behaviour, so I
> won't take for 21.11.4.

This comes from customer issue, it does fix for the usage when latency is critical, will be nice if it can be applied, thanks.

> 
> thanks,
> Kevin.
> 
> > Thanks
> > Qi
> >
> >
> >> ---
> >>   drivers/net/i40e/i40e_ethdev.h | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/net/i40e/i40e_ethdev.h
> >> b/drivers/net/i40e/i40e_ethdev.h index fe943a45ff..7c4cc44a27 100644
> >> --- a/drivers/net/i40e/i40e_ethdev.h
> >> +++ b/drivers/net/i40e/i40e_ethdev.h
> >> @@ -1497,7 +1497,7 @@ i40e_calc_itr_interval(bool is_pf, bool
> is_multi_drv)
> >>   	uint16_t interval = 0;
> >>
> >>   	if (is_multi_drv) {
> >> -		interval = I40E_QUEUE_ITR_INTERVAL_MAX;
> >> +		interval = I40E_QUEUE_ITR_INTERVAL_DEFAULT;
> >>   	} else {
> >>   		if (is_pf)
> >>   			interval = I40E_QUEUE_ITR_INTERVAL_DEFAULT;
> >> --
> >> 2.25.1
> >