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From:   Hayes Wang <hayeswang@realtek.com>
To:     Jakub Kicinski <kuba@kernel.org>
CC:     "Limonciello, Mario" <mario.limonciello@amd.com>,
        "edumazet@google.com" <edumazet@google.com>,
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        "pabeni@redhat.com" <pabeni@redhat.com>,
        "Paul Menzel" <pmenzel@molgen.mpg.de>
Subject: RE: Error 'netif_napi_add_weight() called with weight 256'
Thread-Topic: Error 'netif_napi_add_weight() called with weight 256'
Thread-Index: AQHZw8h1VlKS4AgmjUKpznAl5+SYmK/Tp70AgAAC4ICACvPXQP//7sWAgANr4sD//9pVAIAHlskA
Date:   Mon, 14 Aug 2023 07:07:13 +0000
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Jakub Kicinski <kuba@kernel.org>
> Sent: Thursday, August 10, 2023 2:38 AM
[...]
> High weight will cause higher latency for other softirq and RT
> processing, it's not a good idea. Even with weight/budget of 64
> if there's no higher prio work to do the driver will be polled
> again immediately if it consumed the budget and has more packets.

I mean that only the slow platform uses more than 64 budget,
even I set the weight to 256.
That is, for the fast platform, the actual used budget is always less than 64,
even the weight is 256.

> Do you have some actual data on how the device performs with budget
> of 64 and 256? And maybe perf traces to show where the difference goes?

I tested that slow embedded platform many years ago, so I
don't remember the actual data.
I think the difference is more than 400Mbps.

Best Regards,
Hayes