If someone fixes this upstream via https://github.com/performancecopilot/pcp/issues/656 then we can re-open this BZ, but otherwise we dont have this on the roadmap to be fixed any time soon, so closing wontfix until then.

Ken (upstream) and I worked on the design of this over the last week or so, and he's now implemented it.
We'll merge this new functionality with the planned PCP rebase in 8.4.

This is resolved by upstream commit:

commit 1f73f48fee1d493e1f88c1f9359241c5de6ca64d
Author: Ken McDonell <kenj.au>
Date:   Sat Jul 11 07:03:57 2020 +1000

    Add help text support for derived metrics

Thanks Jan.  I'll review these and maybe see if Mark and Andreas can help with some as well - we'll aim to tackle these remaining ones via the next rebase to pcp-5.2.2.

There's a couple there (event.*) that may not be fixable as they're internal, generated metrics.  I'll see what we can do though and post an update.

Quick question Jan, your missing.help.text.metrics file lists 'proc.hog.disk' - but that one definitely should have help text now:

$ pminfo -t proc.hog.disk -T

proc.hog.disk [average I/O rate of each process since it was started]
Help:
average I/O rate (reads and writes less cancelled writes) of each process
since it was started.


Can you double check that one?  /var/lib/pcp/config/derived/proc.conf contains the metric definition and help text, for reference.

Thanks!

@Nathan: yes, you are right. The "proc.hog.disk" has the help text. That was just an error in my detection script.
I am sorry for the confusion.

I checked all the other metrics from the missing.help.text.metrics file and all of these are missing the help text.

There are 3 new metrics in pcp-5.2.3-1.el8 build missing the online help. This is a partial output of "pminfo -T" command:

network.all.out.packets
Full Help: Error: One-line or help text is not available

network.all.out.errors
Full Help: Error: One-line or help text is not available

network.all.out.drops
Full Help: Error: One-line or help text is not available

Thanks Jan, will back-port in the new year but this one is resolved now via upstream commit:

commit ddd2740e8d0d36d48ed14d75b36aaffa3a725464 (HEAD -> master)
Author: Nathan Scott <nathans>
Date:   Mon Dec 21 13:47:01 2020 +1100

    pmdalinux: add missing help text for new metrics, drop dups
    
    Resolves Red Hat BZ #1670029

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (pcp bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2021:1754