***SPAM*** Re: [ofa-general] [infiniband-diags] add --loop_ports option to perfquery

[Hal Rosenstock]

Hi Al,

On Thu, Oct 9, 2008 at 12:25 PM, Al Chu <chu11 at llnl.gov> wrote:
> Hey Hal,
>
> On Thu, 2008-10-09 at 08:37 -0400, Hal Rosenstock wrote:
>> Hi again Al,
>>
>> On Wed, Oct 8, 2008 at 6:45 PM, Al Chu <chu11 at llnl.gov> wrote:
>> > Hey Hal,
>> >
>> > On Wed, 2008-10-08 at 09:44 -0400, Hal Rosenstock wrote:
>> >> Hi Al,
>> >>
>> >> On Wed, Oct 8, 2008 at 6:26 AM, Al Chu <chu11 at llnl.gov> wrote:
>> >> > Hey Hal,
>> >> >
>> >> > On Wed, 2008-10-08 at 07:03 -0400, Hal Rosenstock wrote:
>> >> >> Al,
>> >> >>
>> >> >> On Tue, Oct 7, 2008 at 6:54 PM, Al Chu <chu11 at llnl.gov> wrote:
>> >> >> > Hey Sasha,
>> >> >> >
>> >> >> > We have a switch here that does not report the AllPortSelect flag as a
>> >> >> > capability.  It's pretty annoying typing each port on the switch or
>> >> >> > always having to script around this one oddball switch we have.  So I
>> >> >> > added an option --loop_ports for perfquery.  If you want to do something
>> >> >> > to all the ports on the CA/Switch, but AllPortSelect isn't available, it
>> >> >> > loops through all the available ports instead.
>> >> >>
>> >> >> Why not add simulated AllPortSelect for multiple ports rather than add
>> >> >> another perquery option for this ?
>> >> >
>> >> > I did try that, and it did seem to work for the switches we had.  But
>> >> > when I read the IB spec, it said something to the affect that if a
>> >> > system doesn't support AllPortSelect, setting the PortSelect field to
>> >> > 0xFF was undefined behavior.
>> >>
>> >> I was suggesting that the emulation support (when AllPortSelect is not
>> >> supported) be enhanced for multiple ports and work on both CAs and all
>> >> switches. The one difference is one response for AllPortSelect
>> >> (whether emulated or not) v. many responses for port loop.
>> >
>> > Oh.  I thought you were referring the the workaround "simulation" that
>> > was in the original code.  But you're referring to aggregating the
>> > data/output make it look like AllPortSelect was supported.  I'll put
>> > this on the TODO.
>>
>> So it seems that the reason for adding an additional option for this
>> is that the lack of this support ? Are there any other uses ?
>
> I made the --loop_ports option b/c I just didn't want to change the
> default behavior perfquery.  But we could easily make it an automatic if
> the AllPortsSelect flag isn't supported.
>
> Thinking about it, there is a bit of a subtlety in the command line
> options and expectations.
>
> If a user inputs a port of '255', to me this means that the user wants
> to do an AllPortSelect and we should error out if AllPortSelect isn't
> supported.
>
> If a user inputs the '-a' option, it suggests that they want perfquery
> to operate on every port, suggesting that we could automatically loop if
> they don't input --loop_ports.

Yes, there is some redundancy now with port 255 and -a option (both do
the same thing) and they could be made subtly different as you
indicate.

In the case of query rather than reset, we are still left with the
question of whether to return 1 aggregated response or 1
response/port. Do we need to support both ? AllPortsSelect has this as
aggregated.

I'm also not sure that the loop ports option is needed.

IMO all that was needed was to loop on the ports when all ports is not
supported by the PMA and aggregate the counters and then nothing else
needs to change.

-- Hal

> Al
>
>> -- Hal
>>
>> >>
>> >> >> > There was already a workaround in the tool for a CA that did not support
>> >> >> > the AllPortSelect flag.  I get the feeling the workaround may have been
>> >> >> > for a specific hardware, so I kept the workaround in there.
>> >> >>
>> >> >> > Al
>> >> >> >
>> >> >> > --
>> >> >> > Albert Chu
>> >> >> > chu11 at llnl.gov
>> >> >> > Computer Scientist
>> >> >> > High Performance Systems Division
>> >> >> > Lawrence Livermore National Laboratory
>> >> >> >
>> >> >> > _______________________________________________
>> >> >> > general mailing list
>> >> >> > general at lists.openfabrics.org
>> >> >> > http://   lists.openfabrics.org/cgi-bin/mailman/listinfo/general
>> >> >> >
>> >> >> > To unsubscribe, please visit http://   openib.org/mailman/listinfo/openib-general
>> >> >> >
>> >> >>
>> >> >> There are also 2 for loops which are not correct for some switches:
>> >> >> for (i = 1; i <= num_ports; i++)
>> >> >
>> >> > I guess I've never seen a switch that doesn't go from 1 to num_ports.
>> >> > Is there something else I need to handle?
>> >>
>> >> Yes, per the spec, enhanced SP0 supports PortCounters. All your
>> >> switches likely support AllPortSelect so it's not an issue there.
>> >
>> > Ok I see now.  Wasn't aware of it.  I'll get a patch together.
>> >
>> > Thanks,
>> > Al
>> >
>> >> -- Hal
>> >>
>> >> > Al
>> >> >
>> >> >> -- Hal
>> >> >>
>> >> > --
>> >> > Albert Chu
>> >> > chu11 at llnl.gov
>> >> > Computer Scientist
>> >> > High Performance Systems Division
>> >> > Lawrence Livermore National Laboratory
>> >> >
>> >> >
>> >>
>> > --
>> > Albert Chu
>> > chu11 at llnl.gov
>> > Computer Scientist
>> > High Performance Systems Division
>> > Lawrence Livermore National Laboratory
>> >
>> >
>>
> --
> Albert Chu
> chu11 at llnl.gov
> Computer Scientist
> High Performance Systems Division
> Lawrence Livermore National Laboratory
>
>