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From:   Ratheesh Kannoth <rkannoth@marvell.com>
To:     Jakub Kicinski <kuba@kernel.org>,
        Alexander Lobakin <aleksander.lobakin@intel.com>
CC:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
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Subject: RE: [EXT] Re: [PATCH net] octeontx2-pf: Set maximum queue size to 16K
Thread-Topic: [EXT] Re: [PATCH net] octeontx2-pf: Set maximum queue size to
 16K
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Date:   Mon, 7 Aug 2023 02:51:24 +0000
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> From: Jakub Kicinski <kuba@kernel.org>
> Sent: Saturday, August 5, 2023 2:05 AM
> To: Alexander Lobakin <aleksander.lobakin@intel.com>
> Subject: Re: [EXT] Re: [PATCH net] octeontx2-pf: Set maximum queue size t=
o
> 16K
>=20
> IDK if I agree with you here :S Tuning this in the driver relies on the
> assumption that the HW / driver is the thing that matters.
> I'd think that the workload, platform (CPU) and config (e.g. is IOMMU
> enabled?) will matter at least as much. While driver developers will end =
up
> tuning to whatever servers they have, random single config and most likel=
y..
> iperf.
>=20
> IMO it's much better to re-purpose "pool_size" and treat it as the ring s=
ize,
> because that's what most drivers end up putting there.
> Defer tuning of the effective ring size to the core and user input (via t=
he "it
> will be added any minute now" netlink API for configuring page pools)...
>=20
> So capping the recycle ring to 32k instead of returning the error seems l=
ike an
> okay solution for now.

Either of the solutions looks Okay to me. Let me push a patch with Jacub's =
proposal for now.  =20
-Ratheesh.=20