[ovs-dev] [PATCH v4] datapath-windows: Enable checksum offloads in STT

[Nithin Raju]

> On Sep 29, 2015, at 5:01 PM, Ben Pfaff <blp at nicira.com> wrote:
> 
> On Tue, Sep 29, 2015 at 01:05:33PM -0700, Jesse Gross wrote:
>> On Tuesday, September 29, 2015, Ben Pfaff <blp at nicira.com
>> <javascript:_e(%7B%7D,'cvml','blp at nicira.com');>> wrote:
>> 
>>> On Wed, Sep 23, 2015 at 08:49:49AM -0700, Jesse Gross wrote:
>>>> On Wed, Sep 23, 2015 at 8:38 AM, Nithin Raju <nithin at vmware.com> wrote:
>>>>>> On Sep 23, 2015, at 8:33 AM, Jesse Gross <jesse at nicira.com> wrote:
>>>>>> 
>>>>>> On Tue, Sep 22, 2015 at 11:04 PM, Nithin Raju <nithin at vmware.com>
>>> wrote:
>>>>>>> hi Jesse,
>>>>>>> We are getting the Hyper-V solution to a state with the following
>>> goals:
>>>>>>> - Work “out of the box” ie. no need to make special settings such as
>>> disabling checksum offload, TSO, etc.
>>>>>>> - Reasonably stable
>>>>>>> 
>>>>>>> Most of the patches we have checked in so far into 2.4 are geared
>>> towards these two goals. Once all of the required changes go in, and we are
>>> reasonably confident about the stability, we can hopefully make an
>>> announcement about Hyper-V support.
>>>>>> 
>>>>>> This is my concern - there should not be any announcements based on
>>>>>> stable branches because there should be no development on stable
>>>>>> branches. The only thing that should go in is targeted bug fixes to
>>>>>> address issues that came up after the release.
>>>>>> 
>>>>>> All of the goals that you listed are good things and make sense - on
>>>>>> the master branch. However, I don't see a need to bring these back to
>>>>>> 2.4. My guess is that there is no more churn in the common code on
>>>>>> master than with the Windows patches here.
>>>>>> 
>>>>>> So please just target 2.5 as the release to make an announcement about
>>>>>> Hyper-V support. I promise that this release cycle won't be as long as
>>>>>> 2.4.
>>>>> 
>>>>> Jesse,
>>>>> We were hoping for a dot release off of 2.4. Like a 2.4.1 or 2.4.2 to
>>> announce support. Would that not be the right release vehicle?
>>>> 
>>>> No, there should be no new features in point releases. 2.5 is the next
>>>> release where it would makes sense to do this. My guess is that will
>>>> be some time around the end of the year.
>>> 
>>> The patches I've seen from the Hyper-V developers so far are just in
>>> Hyper-V specific code, that can't really affect the stability of the
>>> rest of the platform.  I have questions about the value of doing this on
>>> 2.4, given that 2.5 will branch in a reasonable amount of time, but
>>> since they're eager to do it I'm not sure that it's worth discouraging
>>> them ;-)
>>> 
>> 
>> I think it does cause problems for people who want to upgrade OVS in
>> production deployments as often it is not desirable to just take a large
>> set of changes wholesale for a bugfix release. If there are many unrelated
>> commits for feature development it makes it harder to identify what is
>> actually going on. I'm also not sure that it is true that there are no
>> changes to common code.
> 
> Nithin, Alin, et al., why do you guys want this on branch-2.4 so badly?
> Everything that Jesse is saying is right, and despite my initial
> instincts I'm inclined to agree with him in the end.

Ben,
Our goal is to get onto the next earliest release of OVS be it 2.5 or 2.4.1.

If you think that 2.5 will happen soon enough, we can wait for it. Otherwise, we are inclined to request a 2.4.1 release with Hyper-V support.

For now, we can commit to master, and perhaps decide in a month or so as to what the release branch should be. If it turns out to be 2.4.1, we’ll have to do a bunch of crossposts, and I can help with that.

Is that reasonable?

thanks,
-- Nithin