Re: [dpdk-dev] [EXT] Re: [PATCH] eal: add telemetry callbacks for memory info

[Harman Kalra <hkalra@marvell.com>]

> -----Original Message-----
> From: Bruce Richardson <bruce.richardson@intel.com>
> Sent: Monday, September 27, 2021 10:08 PM
> To: Harman Kalra <hkalra@marvell.com>
> Cc: dev@dpdk.org; ciara.power@intel.com; Anatoly Burakov
> <anatoly.burakov@intel.com>
> Subject: Re: [EXT] Re: [PATCH] eal: add telemetry callbacks for memory info
> 
> On Tue, Sep 21, 2021 at 09:05:29AM +0000, Harman Kalra wrote:
> >
> > > -----Original Message-----
> > > From: Bruce Richardson <bruce.richardson@intel.com>
> > > Sent: Monday, September 20, 2021 9:27 PM
> > > To: Harman Kalra <hkalra@marvell.com>
> > > Cc: dev@dpdk.org; ciara.power@intel.com; Anatoly Burakov
> > > <anatoly.burakov@intel.com>
> > > Subject: [EXT] Re: [PATCH] eal: add telemetry callbacks for memory
> > > info
> > >
> > > External Email
> > >
> > > --------------------------------------------------------------------
> > > > Signed-off-by: Harman Kalra <hkalra@marvell.com>
> > > > ---
> > >
> > > For this info, why not just send the data out as telemetry data
> > > rather than writing files on the filesystem containing it? If the
> > > info is too large to dump it all in a single go, a shortened form
> > > could be sent via some form of list call, and additional calls could
> > > be used to provide more detail on specific items in the list.
> > >
> > >  Also, this seems more a debugging operation than a telemetry one,
> > > though I don't have a strong objection to the info being exported as
> > > telemetry directly (just not via filesystem).
> > >
> > > Regards,
> > > /Bruce
> >
> >
> > Hi Bruce,
> >
> > Thanks for reviewing the patch.
> > I have implemented these telemetry commands as a wrapper which uses
> > existing malloc/memzone debug APIs to collect the debug information,
> these debug APIs are implemented in the way that they accept a file
> pointer/stdout.
> > to get the information.
> >
> > As a solution either  I should make changes to these debug APIs to
> > accept a buffer also? Or other way could be get the info dumped into a file,
> and inside telemetry command parse and convert the info into json format
> and send it.
> > But its lot of debug information so will require multiple iterations
> > as you suggested. But on client (peer) side one will have to again convert
> json to retrieve the info.
> >
> > Just for my understanding, what drawback do you see in dumping the
> > information to a file? Because on peer side It is very convenient to read the
> information from dumped file and use it.
> >
> 
> Hi
> 
> The drawback is largely a philosophical one in that what you add here are
> not read-operations for telemetry, but rather commands which cause the
> application to make changes on the running system - i.e. write out files.
> It's certainly something we could look to do, but I think we should only do so
> with some careful thought, rather than just adding it ad-hoc.

Hi Bruce

I have started working on this, and will come up with proper implementation as suggested.

Thanks
Harman

> 
> Regards,
> /Bruce