in procstat input plugin, process_name tag should be tagged not only procstat measurement but procstat_lookup measurement.

[Jaeyo]

Feature Request

in procstat input plugin, process_name tag also tagged in procstat_lookup measurement.

Proposal:

Current behavior:

procstat input plugin produce two measurement: procstat, procstat_lookup.
and process_name tag only tagged with procstat measurement.

# tag list
- procstat measurement
  - host
  - pattern
  - process_name
  - user
- procstat_lookup measurement
  - host
  - pattern

Desired behavior:

process_name should be tagged with procstat_lookup measurement also.

Use case: [Why is this important (helps with prioritizing requests)]

i'm checking specific processes aliveness with procstat_lookup measurement with pid_count field. if process_name tagged with procstat_lookup measurement, i think i can check it more clearly.

[danielnelson]

During the lookup we don't know the process name yet, and the lookup may return multiple processes with differing names. One exception to this might be if it is set statically with the process_name option, though I'd like to do #3362 and then deprecate this option.

If you are setting the process_name, or even if not but you have a good idea of what it should be statically then you can use the tags option:

[[inputs.procstat]]
  [inputs.procstat.tags]
    process_name = "foo"

[tushar2013]

this does not overwrite the process_name tag of procstat measurement.
so if procstat if getting a name "foo" from /proc/<pid>/status and then you do above to set process_name as "my_foo"
then procstat_lookup will definitely have a tag as "process_name=my_foo" but procstat will still have "process_name=foo"