cg_diff - Linux

Overview

cg_diff is a powerful command-line tool for comparing two control groups (cgroups) and highlighting their differences. It provides a detailed view of the configuration parameters, hierarchies, and resource limits set for each cgroup, enabling users to quickly identify and analyze variations between them.

Syntax

cg_diff [OPTIONS] CGROUP1 CGROUP2

Options/Flags

• -a, –all: Compare all parameters, including inherited values.
• -e, –exclude-inherited: Exclude inherited values from comparison.
• -h, –help: Display brief help information.
• -i, –ignore-case: Ignore case differences in parameter values.
• -n, –numeric: Output numeric values for parameters.
• -q, –quiet: Suppress output of identical parameters.
• -s, –skip-keys: Skip comparison of specified parameter keys.
• -t, –tree: Display differences in a tree-like format.
• -v, –verbose: Display more verbose output.

Examples

Simple Comparison:

cg_diff /sys/fs/cgroup/cpuset/user1 /sys/fs/cgroup/cpuset/user2

Verbose Comparison (with Tree Format):

cg_diff -tv /sys/fs/cgroup/memory/group1 /sys/fs/cgroup/memory/group2

Ignore Inherited Values:

cg_diff -ea /sys/fs/cgroup/memory/user1 /sys/fs/cgroup/memory/user2

Common Issues

• Incorrect Cgroup Paths: Ensure that the provided cgroup paths are valid.
• Permission Denied: Verify that you have sufficient permissions to access the cgroup filesystems.
• Parameter Not Found: Check that the specified parameter key exists in the cgroups being compared.

Integration

Combine with ‘cgget’ for Advanced Analysis:

cgget -a /sys/fs/cgroup/memory/group1 | cg_diff -

Create Ansible Playbooks for Cgroup Management:

- name: Compare cgroups
  cg_diff:
    target: /sys/fs/cgroup/memory/
    group1: group1
    group2: group2

Related Commands

• cgcreate
• cgdelete
• cgset
• cgget