System Memory Fragmentation icon

System Memory Fragmentation

System Memory Fragmentation

Plugin: debugfs.plugin Module: /sys/kernel/debug/extfrag


Collects memory fragmentation statistics from the Linux kernel

Parse data from debugfs file

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 files under /sys/kernel/debug/extfrag, which are accessible only to the root user by default. Netdata uses Linux Capabilities to give the plugin access to debugfs. 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 so that it runs as root.

Default Behavior


Assuming that debugfs is mounted and the required permissions are available, this integration will automatically run by default.


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.




The debugfs filesystem must be mounted on your host for plugin to collect data. You can run the command-line (sudo mount -t debugfs none /sys/kernel/debug/) to mount it locally. It is also recommended to modify your fstab (5) avoiding necessity to mount the filesystem before starting netdata.



The configuration file name for this integration is netdata.conf. Configuration for this specific integration is located in the [plugin:debugfs] section within that file.

The file format is a modified INI syntax. The general structure is:

    option1 = some value
    option2 = some other value

    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


Name Description Default Required
update every Data collection frequency. 1 no
command options Additinal parameters for collector no


There are no configuration examples.


Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Monitor the overall memory fragmentation of the system.

Per node

Memory fragmentation statistics for each NUMA node in the system.


Label Description
numa_node The NUMA node the metrics are associated with.


Metric Dimensions Unit
mem.fragmentation_index_dma order0, order1, order2, order3, order4, order5, order6, order7, order8, order9, order10 index
mem.fragmentation_index_dma32 order0, order1, order2, order3, order4, order5, order6, order7, order8, order9, order10 index
mem.fragmentation_index_normal order0, order1, order2, order3, order4, order5, order6, order7, order8, order9, order10 index


There are no alerts configured by default for this integration.

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