Guru can log runtime configuration of a given process, along with thread status and greenthread status. It greatly help check the process runtime status. The usage is simple: kill -USR2 {process-id} In dragonflow, you can show the reports of df-controller, df-publisher, df-l3-agent, and the coming df-metadata-service. The description is as follows: https://wiki.openstack.org/wiki/GuruMeditationReport Closes-Bug: #1568220 Change-Id: I24048e1018ba3710b7a7476ca1dd83a5ae38894a
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Guru Meditation Reports
Dragonflow contains a mechanism whereby developers and system administrators can generate a report about the state of a running Dragonflow executable. This report is called a Guru Meditation Report (GMR for short).
Generating a GMR
A GMR can be generated by sending the USR2 signal to any Dragonflow process with support (see below). The GMR will then be outputted standard error for that particular process.
For example, suppose that df-local-controller
has
process id 2525
, and was run with
2>/var/log/dragonflow/df-controller.log
. Then,
kill -USR2 2525
will trigger the Guru Meditation report to
be printed to /var/log/dragonflow/df-controller.log
.
Structure of a GMR
The GMR is designed to be extensible; any particular executable may add its own sections. However, the base GMR consists of several sections:
- Package
-
Shows information about the package to which this process belongs, including version information
- Threads
-
Shows stack traces and thread ids for each of the threads within this process
- Green Threads
-
Shows stack traces for each of the green threads within this process (green threads don't have thread ids)
- Configuration
-
Lists all the configuration options currently accessible via the CONF object for the current process
Adding Support for GMRs to New Executables
Adding support for a GMR to a given executable is fairly easy.
First import the module, as well as the Dragonflow version module:
from oslo_reports import guru_meditation_report as gmr
from dragonflow import version
Then, register any additional sections (optional):
'Some Special Section',
TextGuruMeditation.register_section( some_section_generator)
Finally (under main), before running the "main loop" of the executable, register the GMR hook:
TextGuruMeditation.setup_autorun(version)
Extending the GMR
As mentioned above, additional sections can be added to the GMR for a
particular executable. For more information, see the inline
documentation under oslo.reports