[dpdk-dev] Question about telemetry on 18.11 release

[Hideyuki Yamashita]

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.

Thanks in advance.

BR,
Hideyuki Yamashita
NTT TechnoCross