Re: [RFC PATCH net-next v2 0/7] Improve GbEth performance on Renesas RZ/G2L and related SoCs

From: Sergey Shtylyov
Date: Tue Feb 13 2024 - 04:44:21 EST


On 2/12/24 11:53 PM, Sergey Shtylyov wrote:
[...]

>>>> This series aims to improve peformance of the GbEth IP in the Renesas
>>>
>>> You didn't fix the typo in "peformance"... :-/
>>>
>>>> RZ/G2L SoC family and the RZ/G3S SoC, which use the ravb driver. Along
>>>> the way, we do some refactoring and ensure that napi_complete_done() is
>>>> used in accordance with the NAPI documentation for both GbEth and R-Car
>>>> code paths.
>>>>
>>>> Performance improvment mainly comes from enabling SW IRQ Coalescing for
>>>
>>> And in "improvment" too... :-/
>>
>> I'll fix this and the above type in v3.
>
> TIA! Chances are this will end up in the merge commit...
>
>>>> all SoCs using the GbEth IP, and NAPI Threaded mode for single core SoCs
>>>> using the GbEth IP. These can be enabled/disabled at runtime via sysfs,
>>>> but our goal is to set sensible defaults which get good performance on
>>>> the affected SoCs.
>>>>
>>>> The performance impact of this series on iperf3 testing is as follows:
>>>> * RZ/G2L Ethernet throughput is unchanged, but CPU usage drops:
>>>> * Bidirectional and TCP RX: 6.5% less CPU usage
>>>> * UDP RX: 10% less CPU usage
>>>>
>>>> * RZ/G2UL and RZ/G3S Ethernet throughput is increased for all test
>>>> cases except UDP TX, which suffers a slight loss:
>>>> * TCP TX: 32% more throughput
>>>> * TCP RX: 11% more throughput
>>>> * UDP TX: 10% less throughput
>>>> * UDP RX: 10183% more throughput - the previous throughput of
>>>
>>> So this is a real figure? I thought you forgot to erase 10... :-)
>>
>> Yes, throughput went from 1.06Mbps to 109Mbps for the RZ/G2UL with these
>> changes.
>
> Hm, that gives me even 10283%! :-)

Stupid me, forgot to subtract 100%... :-)

[...]

MBR, Sergey