1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
..
Except where otherwise noted, this document is licensed under Creative
Commons Attribution 3.0 License. You can view the license at:
https://creativecommons.org/licenses/by/3.0/
.. _watcher_gmr:
=======================
Guru Meditation Reports
=======================
Watcher contains a mechanism whereby developers and system administrators can
generate a report about the state of a running Watcher service. 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 Watcher process
with support (see below). The *GMR* will then be outputted as standard error
for that particular process.
For example, suppose that ``watcher-api`` has process id ``8675``, and was run
with ``2>/var/log/watcher/watcher-api-err.log``. Then, ``kill -USR2 8675``
will trigger the Guru Meditation report to be printed to
``/var/log/watcher/watcher-api-err.log``.
Structure of a GMR
==================
The *GMR* is designed to be extensible; any particular service 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.
Plugins
Lists all the plugins currently accessible by the Watcher service.
|
