Just a quick note to say that I've closed the survey.
I haven't published the results yet as I said that I would write notes
necessary as a preamble to correctly inform potential readers,
and these notes are taking longer to write than I have time available.
Cheers,
Etienne
On Wed, Feb 24, 2021 at 7:07 PM Etienne-Victor Depasquale
wrote:
> I think I need to calm this thread down.
>
> I'm a researcher, and my interest is in the truth, not in my opinion.
>
> I've read some facts in this thread that are necessary
> as a prerequisite to the publication of the results on Friday.
>
> I do want to ensure that no future reader is misinformed and will do my
> best,
> with the help of contribution from my peers in this good community,
> to summarize all objections to this survey's questions,
> in the same message as that which publishes the result.
>
> All peace and good wishes,
>
> Etienne
>
> On Wed, Feb 24, 2021 at 4:35 PM Robert Bays wrote:
>
>> To the nanog community, I’m sorry to have dragged this conversation out
>> further. I'm only responding to this because there are a significant
>> number of open source projects and commercial products that use DPDK, or
>> similar userspace network environment in their implementations. The
>> statements in this thread incorrectly cast them, because they use DPDK, as
>> inefficient. But the reality is they have all been designed from day one
>> not to unnecessarily consume power. Please ask your open source dev and/or
>> vendor of choice to verify. But please don’t rely on the information in
>> this thread to make decisions about what you deploy in your network.
>>
>> On Feb 23, 2021, at 11:44 PM, Etienne-Victor Depasquale
>> wrote:
>>
>> Hello Robert,
>>
>> Your statement that DPDK “keeps utilization at 100% regardless of packet
>>> activity” is just not correct. You further pre-suppose "widespread DPDK's
>>> core operating inefficiency” without any data to backup the operating
>>> inefficacy assertion.
>>>
>>
>> This statement is incorrect.
>> I have provided references (please see earlier e-mails) that investigate
>> the operation of DPDK.
>> These references are items of peer-reviewed research that investigate a
>> perceived problem with deployment of DPDK.
>> If the power consumption incurred while running DPDK were a corner case,
>> then there would be little to no research value in investigating such
>> behavior.
>>
>>
>> Your references don’t take into account the code that this community
>> would actually deploy; open source implementations like DANOS, FD.io, or
>> OVS. They don’t audit any commercial products that implement userspace
>> stacks. None of your references say that DPDK is inherently inefficient.
>> The closest they come is to say that tight polling is inefficient. But
>> tight polling, even in the earliest days of DPDK, was never meant to be a
>> design pattern that was actually deployed into production. I was there for
>> those early conversations.
>>
>> Please don’t mislead the community into believing that DPDK == power bad
>>>
>> I have to object to this statement. It does seem to imply malice, or, at
>> best, amateurish behaviour, whether you intended it or not.
>>
>>
>> Object all you want. You are misleading people with your comments. And
>> in the process you are denigrating a large swath of OSS projects and
>> commercial products that use DPDK. Your survey questions are leading and
>> provide a false dichotomy. And when you post the results here, they will
>> be archived forever to continue to spread misinformation, unfortunately.
>>
>> Everything following is informational. Stop here if so inclined.
>>>
>> Please stop delving into the detail of DPDK's facilities without regard
>> for your logical omission:
>> that whether the facilities are available or not, DPDK's deployment
>> profile (meaning: how it's being used in general), as indicated by the
>> references I've provided,
>> are leading to high power inefficiency on cores partitioned to the data
>> plane.
>>
>>
>> I’ve been writing network appliance code for over 20 years. I designed
>> network architectures for years before that. I have 10s of thousands of
>> DPDK based appliances in production at this moment across multiple
>> different use cases. I work with companies that have 100s of thousands of
>> units in production that leverage userspace runtimes. I do think I
>> understand DPDK’s deployment profile better than you. That’s what I have
>> been trying to tell you. People don’t write inefficient DPDK code to put
>> into production. We’re not dumb. We’ve been thinking about power
>> consumption from day one. DPDK was never supposed to be just a tight loop
>> poll. You were always supposed to put in the very minimal extra work to
>> modulate power consumption.
>>
>> The takeaway is that DPDK (and similar) doesn’t guarantee runaway power
>>> bills.
>>>
>> Of course it doesn't.
>> Even the second question of that bare-bones survey tried to
