Re: stmmac / meson8b-dwmac

[Simon Huelck <simonmail@gmx.de>]

Hi,

4.17.9 failed going back further

regards,
Simon

Am 06.02.2019 um 11:36 schrieb Emiliano Ingrassia:
> Hi Martin, Hi Simon,
>
> On Mon, Feb 04, 2019 at 03:34:41PM +0100, Martin Blumenstingl wrote:
>> On Thu, Jan 17, 2019 at 10:23 PM Simon Huelck <simonmail@gmx.de> wrote:
>> [...]
>>>>> I got problems with my ODROID c2 running on 4.19.16 ( and some releases
>>>>> earlier ). the stmmac / dwmac driver doesnt provide the 800M/900M
>>>>> performance that i was used to earlier.
>>>>>
> Simon, did you ever reach 1 Gbps full duplex speed?
> If yes, what was the kernel version did you use?
>
>>>>> Now im stuck near 550M/600M in the same environment. but what really
>>>>> confuses me that duplex does hurt even more.
>>>> interesting that you see this on the Odroid-C2 as well.
>>>> previously I have only observed it on an Odroid-C1
>>>>
>>>>> PC --- VLAN3 --> switch --VLAN3--> ODROID
>>>>>
>>>>> NAS <-- VLAN1 -- switch <-- VLAN1-- ODROID
>>>>>
>>>>>
>>>>> this means when im doing a iperf from PC to NAS, that my ODROID has load
>>>>> on RX/TX same time (duplex). this shouldnt be an issue , all is 1GBits
>>>>> FD. And in the past that wasnt an issue.
>> +Cc Emiliano who has seen a similar duplex issue on his Odroid-C1: [0]
>> (please note that all kernels prior to v5.1 with the pending patches
>> from [1] applied are only receiving data on RXD0 and RXD1 but not on
>> RXD2 and RXD3)
>>
>> Emiliano, can you confirm the duplex issue observed by Simon is
>> similar to the one you see on your Odroid-C1?
>>
> It could be but, if I understand correctly, Simon is limited in
> speed also in half duplex transmission (~550/600 Mbps), while we can
> reach at least 900 Mbps.
>
>>>>>
>>>>> Now what happens:
>>>>>
>>>>> - benchmark between PC - ODROID is roughly 550M
>>>>>
>>>>> - benchmark between NAS - ODROID is roughly 550M
>>>>>
>>>>> - benchmark between PC - NAS is only around 300M
>>>>>
>>>>>
>>>>> and like i said i was easliy able to hit 800 or even 900M to my NAS
>>>>> earlier. I applied some .dtb fixes for interrupt levels for the
>>>>> meson-gx.dtsi and meson-gxbb-odroid-c2.dtb, which will be mainlined ,
>>>>> but the effect stayed identical.
>>>> good that you have the interrupt patches already applied
>>>> I believe it don't fix any performance issues - it's a fix for the
>>>> Ethernet controller seemingly getting "stuck" (not processing data
>>>> anymore). however, that already rules out one potential issue
>>>>
>>>>> are you aware of this problem ? Earlier kernel versions were all
>>>>> perfectly fine and i stepped ( self compiled) kernel through all major
>>>>> releases since odroid c2 was mainlined.
>> Guiseppe, Alexandre: what kind of data do you need from us if we see
>> the speeds drop (in both directions) when we send and receive at the
>> same time?
>>
>> [...]
>>> the problem is that i dont have these kernel sources anymore :-(. but i
>>> can provide some testing and numbers. maybe i dig if i got these kernel
>>> configs somewhere around but i did not change much during migrating
>> do you remember the kernel version where it worked fine?
>>
>>> im using a zyxel gs1900-8 switch and a qnap ts231p , and as i said i
>>> didnt change my setup. i was able to hit 100MByte/s from my NAS , so
>>> close to the benchmarks of 900MBit/s
>> I typically only do small transfers or I have traffic only in one direction.
>> thus it's likely that I missed this in my own tests
>>
>>
>> Regards
>> Martin
>>
>>
>> [0] http://lists.infradead.org/pipermail/linux-amlogic/2018-December/009679.html
>> [1] https://patchwork.kernel.org/cover/10744905/
> Regards,
>
> Emiliano