Linux kernel SLAB allocator statistics
Linux kernel SLAB allocator statistics
Plugin: slabinfo.plugin Module: slabinfo.plugin
Overview
Collects metrics on kernel SLAB cache utilization to monitor the low-level performance impact of workloads in the kernel.
The plugin parses /proc/slabinfo
This collector is only supported on the following platforms:
- Linux
This collector only supports collecting metrics from a single instance of this integration.
This integration requires read access to /proc/slabinfo, which is accessible only to the root user by default. Netdata uses Linux Capabilities to give the plugin access to this file. CAP_DAC_READ_SEARCH is added automatically during installation. This capability allows bypassing file read permission checks and directory read and execute permission checks. If file capabilities are not usable, then the plugin is instead installed with the SUID bit set in permissions sVko that it runs as root.
Default Behavior
Auto-Detection
Due to the large number of metrics generated by this integration, it is disabled by default and must be manually enabled inside /etc/netdata/netdata.conf
Limits
The default configuration for this integration does not impose any limits on data collection.
Performance Impact
The default configuration for this integration is not expected to impose a significant performance impact on the system.
Setup
Prerequisites
Minimum setup
If you installed netdata using a package manager, it is also necessary to install the package netdata-plugin-slabinfo.
Configuration
File
The configuration file name for this integration is netdata.conf.
Configuration for this specific integration is located in the [plugins] section within that file.
The file format is a modified INI syntax. The general structure is:
[section1]
option1 = some value
option2 = some other value
[section2]
option3 = some third value
You can edit the configuration file using the edit-config script from the
Netdata config directory.
cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config netdata.conf
Options
| Name | Description | Default | Required |
|---|---|---|---|
| Enable plugin | As described above plugin is disabled by default, this option is used to enable plugin. | no | yes |
Examples
There are no configuration examples.
Metrics
Metrics grouped by scope.
The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.
SLAB cache utilization metrics for the whole system.
Per Linux kernel SLAB allocator statistics instance
This scope has no labels.
Metrics:
| Metric | Dimensions | Unit |
|---|---|---|
| mem.slabmemory | a dimension per cache | B |
| mem.slabfilling | a dimension per cache | % |
| mem.slabwaste | a dimension per cache | B |
Alerts
There are no alerts configured by default for this integration.