> On Jan 20, 2020, at 4:47 AM, Hrvoje Popovski <[email protected]> wrote:
> 
> On 16.1.2020. 18:45, Scott Cheloha wrote:
>> Here's a first batch of conversions: rx refill timeouts for bnxt(4),
>> myx(4), and vr(4).  All of these can run during a softclock().  Will
>> changing these to one tick break these drivers?
> 
> Hi all,
> 
> i tried this diff with myx and performance are the same as with plain
> kernel.
> 
> myx0 at pci4 dev 0 function 0 "Myricom Z8E" rev 0x01: msi, model
> 10G-PCIE2-8BL2-2S, address 00:60:dd:45:ba:f8
> myx1 at pci5 dev 0 function 0 "Myricom Z8E" rev 0x01: msi, model
> 10G-PCIE2-8BL2-2S, address 00:60:dd:45:ba:f9

Appreciate the testing.

Given what dlg@ has said in the past I think there should only be a
performance change in a livelock situation.

What metric did you use to compare performance?

I think you could induce a livelock with tcpbench(8) or iperf3 from ports.
CC'd bluhm@, who would know more.

To be clear, I'm of the opinion that we should not be spinning the softclock()
unless the alternative is palpably reduced performance for a significant group
of users.  However, I don't want to tread on network performance without 
analysis
and buy-in from the people who work on that, hence all the CCs.

Probably missing a few CCs, but I figured I'd start with the API and driver
authors.

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