[ofa-general] [PATCH 5/7 V3] osm: QoS - adding QoS policy options

[Sasha Khapyorsky]

On 04:19 Thu 30 Aug     , Yevgeny Kliteynik wrote:
>  Sasha Khapyorsky wrote:
> > On 19:12 Wed 29 Aug     , Hal Rosenstock wrote:
> >> On 8/29/07, Sasha Khapyorsky <sashak at voltaire.com> wrote:
> >>> On 17:48 Wed 29 Aug     , Hal Rosenstock wrote:
> >>>>> OK, there are three ways we want this thing to work:
> >>>>> 1. QoS is off
> >>>>> 2. The old QoS is on but w/o policy file
> >>>>> 3. The old QoS is on, plus reading policy file
> >>>>>
> >>>>> The first option is clear: if a user doesn't turns QoS on (-Q), QoS is 
> >>>>> off as before.
> >>>>>
> >>>>> Second and third options: if QoS is on, OpenSM looks for policy file in 
> >>>>> the default
> >>>>> location or in other location that was provided by user. If the file is 
> >>>>> not found,
> >>>>> QoS works as before.
> >>>> This sounds OK to me and is my first preference.
> >>>>
> >>>>> Do we want to add additional option for "enhanced" QoS?
> >>>>> If so, we will have three QoS-ralated command line options:
> >>>>>  - option for turning the QoS on (currently -Q)
> >>>>>  - option to turn the new QoS on (some new letter - must get
> >>>>>    one quick before they all run out... :)
> >>>>>  - option for policy file location if differs from default (currently 
> >>>>> -Y)
> >>>> This seems like the least preferable to me. Also, would need to deal
> >>>> with both on which seems to mean use new QoS.
> >>>>
> >>>>> Alternatively, we can turn -Q option into levels:
> >>>>>  -Q 0: QoS is off (default)
> >>>>>  -Q 1: old QoS is on
> >>>>>  -Q 2: old QoS plus reading policy file
> >>>> This one also seems OK to me (second preference).
> >>>>
> >>>> Anyone else with an opinion on this ? Sasha ?
> >>> I like -Q and -Y as Yevgeny proposed.
> >> So is that the first option ?
> > Yes. It is simplest and provides the same functionality.
> 
>  This is what's implemented right now
> 
> >> Actually, I think I like the third option best now that I think more
> >> on this. It seems a little odd to me to rely on the policy file not
> >> being present to determine which QoS to run. Seems a little cleaner
> >> this way to me.
> > We need file name option anyway, so things like '-Q 1 -Y ...' are
> > unclear. Also it would be nice to have "universal" (not for "two QoS")
> > user interface in order to not change it later.
> 
>  I would say that -Q and -Y are enough, but it poses some questions:
>  Do we want to allow the case when a user has policy file in a default
>  location, but he wants OpenSM to ignore this file and still have QoS on?

-Y '' should be fine then.

>  In case of partitions file we don't have an option to ignore partition
>  config file in a default location.
> 
>  And if OpenSM ignores policy file, what would it mean?
>  Would it be the "old" QoS?

Yes. Is there another useful options?

>  And when the setup part of the new QoS will be ready, would we still want
>  the SL2VL and VLArb tables to appear in the opts file?

Don't think. Why we need it in two places?

Sasha