# Memory Metrics

The **mem** input plugin, gathers the information about the memory and swap usage of the running system every certain interval of time and reports the total amount of memory and the amount of free available.

## Configuration Parameters

The plugin supports the following configuration parameters:

| Key           | Description                                                                                                                                                                    | Default |
| ------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------- |
| Interval\_Sec | Polling interval in seconds                                                                                                                                                    | 1       |
| PID           | Specify the ID (PID) of a running process in the system. By default the plugin monitors the whole system but if this option is set, it will only monitor the given process ID. |         |

## Getting Started

In order to get memory and swap usage from your system, you can run the plugin from the command line or through the configuration file:

### Command Line

```bash
$ fluent-bit -i mem -t memory -o stdout -m '*'
Fluent Bit v1.x.x
* Copyright (C) 2019-2020 The Fluent Bit Authors
* Copyright (C) 2015-2018 Treasure Data
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

[2017/03/03 21:12:35] [ info] [engine] started
[0] memory: [1488543156, {"Mem.total"=>1016044, "Mem.used"=>841388, "Mem.free"=>174656, "Swap.total"=>2064380, "Swap.used"=>139888, "Swap.free"=>1924492}]
[1] memory: [1488543157, {"Mem.total"=>1016044, "Mem.used"=>841420, "Mem.free"=>174624, "Swap.total"=>2064380, "Swap.used"=>139888, "Swap.free"=>1924492}]
[2] memory: [1488543158, {"Mem.total"=>1016044, "Mem.used"=>841420, "Mem.free"=>174624, "Swap.total"=>2064380, "Swap.used"=>139888, "Swap.free"=>1924492}]
[3] memory: [1488543159, {"Mem.total"=>1016044, "Mem.used"=>841420, "Mem.free"=>174624, "Swap.total"=>2064380, "Swap.used"=>139888, "Swap.free"=>1924492}]
```

### Configuration File

In your main configuration file append the following *Input* & *Output* sections:

```python
[INPUT]
    Name   mem
    Tag    memory

[OUTPUT]
    Name   stdout
    Match  *
```


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