numa and taskqueues

[Adrian Chadd]

On 31 May 2017 at 06:53, Emeric POUPON <emeric.poupon at stormshield.eu> wrote:
>
>>>
>>> Actually, there is a performance boost only when few flows are involved.
>>> That's why this is not activated by default and a sysctl is here to enable the
>>> feature.
>>>
>>> To sum up, the more different flows you process (both ciphered and unciphered),
>>> the more network queues are hit and the more CPU units are triggered from
>>> ipsec.
>>> In this case, we indeed notice a loss, certainly due to the extra
>>> queing/reordering performed.
>>
>> Can you dig into that a bit more? Do you know exactly what's going on?
>> eg, is it a "lock contention" problem? Is it a "stuff is context
>> switching, thus latency" problem? etc, etc.
>>
>
> Unfortunately I cannot tell you the exact reason right now.
> I am sure there is no lock contention involved though (except of course when several domains are involved).
> Did you expect such a dev to be enabled by default?

Well, I'd really like to get to the bottom of these. :-P



-adrian