From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: Question about telemetry on 18.11 release
Date: Wed, 21 Nov 2018 11:38:25 +0000
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Cc: Harry Van Haaren <harry.van.haaren@intel.com>,
 "Laatz, Kevin" <kevin.laatz@intel.com>,
 Bruce Richardson <bruce.richardson@intel.com>
To: Hideyuki Yamashita <yamashita.hideyuki@po.ntt-tx.co.jp>, dev@dpdk.org
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On 11/21/2018 7:48 AM, Hideyuki Yamashita wrote:
> Hello,
> 
> I have some basic questions about telemetry API
> which is planned to be relaesed in 18.11.
> 
> Note that I have read the follwoing document.
> https://doc.dpdk.org/guides/howto/telemetry.html
> 
> Q1. In general dpdk application use polling when
> receiving packets. So CPU usage is always looks 100%
> when measured using e.g. vmstat even if there is no packet receiving.
> (CPU is busy for polling packets)
> Is that correct?
> 
> Q2. Is it correct understanding that dpdk application 
> can send "any" value(or metric) to client if client
> requested via "telemetry" framework?
> 
> Q3.Is it possible to query "real cpu usage" from dpdk
> application using "telemetry" framework?
> ("real cpu usage" I mean if 0 pakcket incoming,
> cpu usage indicates almost 0 %)
> 
> Q4. Is it possible to inform client about fault or some
> trouble from dpdk application?
> 
> Background  I ask above is that 
> - I am relative new to DPDK world and have almost no knowledge about
> "telemetry"
> - I am interested in how dpdk applications can "scales" on platform
> like OpenStack. I think some mesurement mechanism required
> and I thought it might be "telemetry" APIs.

Briefly I think yes, telemetry can be measurement mechanism and interface to
external application. Cc'ed Harry & Kevin for more detailed answers.

> 
> Thanks in advance.
> 
> BR,
> Hideyuki Yamashita
> NTT TechnoCross
> 
>