I/OAT ... Coming Soon ?

[Andre Oppermann]

Jack Vogel wrote:
> On Nov 14, 2007 5:52 PM, Julian Elischer <julian at elischer.org> wrote:
>> Jack Vogel wrote:
>>> On Nov 14, 2007 5:01 PM, Wilkinson, Alex
>>> <Alex.Wilkinson at dsto.defence.gov.au> wrote:
>>>> Hi all,
>>>>
>>>> Curious, is I/OAT [http://www.intel.com/go/ioat/] coming to FreeBSD soon
>>>> ?
>>> LOL, I did a driver for the first version of I/OAT more than a year
>>> ago, submitted
>>> it and interest was half hearted.
>>>
>>> The driver needs updating and polishing yet, but interest being what it was
>>> it hasn't been a real high priority.
>>>
>> I saw what I thought you called a "preliminary" driver.
>> There was discussion and I thought you got positive but
>> muted (along the lines of "nice.. when will there be hardware for it?")
>> and some discussion of how it fits in with TCP offload, but I don't think
>> that anyone said they didn't like the idea..
>>
>> hmm didn't someone else have an implementation? or am I getting
>> my wires crossed on that?
> 
> You are probably right, its been quite a while, and there were
> other factors that have effected my perception.
> 
> The driver just for the engine didn't require the stack portion
> that Prafulla did, although we need something using the thing :)

I/OAT helps with the userland/kernel copying by offloading it into
the chipset memory controller.  The right place to hook it isn't
really the network stack but copyin/copyout and equivalents.
m_uiotombuf and uiomove in this case for sockets.

> Not sure what other implementation you are thinking of. Linux has it
> of course.
> 
> I'd be glad to resurrect the code and get on with it in any case.

-- 
Andre