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
53
54
55
56
57
58
59
60
61
|
# Prometheus metrics for `pgagroal`
This tutorial will show you how to do basic [Prometheus](https://prometheus.io/){:target="_blank"} setup for `pgagroal`.
`pgagroal` is able to provide a set of metrics about what it is happening within the pooler,
so that a Prometheus instance can collect them and help you monitor the pooler.
## Preface
This tutorial assumes that you have already an installation of PostgreSQL 10 (or higher) and `pgagroal`.
In particular, this tutorial refers to the configuration done in [Install pgagroal](https://github.com/pgagroal/pgagroal/blob/master/doc/tutorial/01_install.md).
## Change the pgagroal configuration
In order to enable to export of the metrics, you need to add the `metrics` option in the main `pgagroal.conf` configuration. The value of this setting is the TCP/IP port number that Prometheus will use to grab the exported metrics.
Add a line like the following to `/etc/pgagroal/pgagroal.conf` by editing such file with your editor of choice:
```
metrics = 2346
```
Place it withingr the `[pgagroal]` section, like
```
[pgagroal]
...
metrics = 2346
```
This will bind the TCP/IP port number `2346` to the metrics export.
See [the `pgagroal` configuration settings](https://github.com/agroal/pgagroal/blob/master/doc/CONFIGURATION.md#pgagroal) with particular regard to `metrics`, `metrics_cache_max_age` and `metrics_cache_max_size` for more details.
## Restart pgagroal
In order to apply changes, you need to restart `pgagroal`, therefore run the following commands
as the `pgagroal` operating system user:
```
pgagroal-cli -c /etc/pgagroal/pgagroal.conf shutdown
pgagroal -c /etc/pgagroal/pgagroal.conf -a /etc/pgagroal/pgagroal_hba.conf
```
If you need to specify other configuration files, for example for remote management (see [the related tutorial](https://github.com/pgagroal/pgagroal/blob/master/doc/tutorial/03_remote_management.md)), add them on the `pgagroal` command line.
If the cofiguration files have standard names, you can omit them.
## Get Prometheus metrics
Once `pgagroal` is running you can access the metrics with a browser at the pooler address, specifying the `metrics` port number and routing to the `/metrics` page. For example, point your web browser at:
```
http://localhost:2346/metrics
```
It is also possible to get an explaination of what is the meaning of each metric by pointing your web browser at:
```
http://localhost:2346/
```
|
