chrt - Linux

Overview

chrt is a command used to set or change scheduling attributes of a running process or a command about to be executed. It is primarily used to adjust the scheduling policy and priority of the target process, enabling finer control over CPU resource allocation.

Syntax

chrt [options] [priority] [command] [args]

Parameters:

• priority: The scheduling priority, expressed as a numeric value from -20 (lowest) to 19 (highest). Default: 0
• command: The command to execute with the specified scheduling attributes

Options/Flags:

• -p: Specify priority explicitly
• -i: Set priority of the calling process
• -f: Apply the attributes to a future process (must be followed by a command)
• -e: Display effective priority
• -d: Display current scheduling policy
• -m: Modify current scheduling policy

Examples

Increase the priority of the current process:

chrt -p 10

Run a new command with a specific priority:

chrt -p 15 taskmanager

Set the priority of a future process:

chrt -f 5 firefox

Display the effective priority of a process:

chrt -e 4007

Common Issues

• Permission denied: Ensure the user has sufficient privileges to adjust process scheduling.
• Invalid priority: The specified priority must be within the range of -20 to 19.
• Process not found: Verify that the process you’re trying to modify is still running.

Integration

chrt can be used in conjunction with other tools for advanced task management:**

• nice: Adjust the static priority of a process
• ionice: Control the I/O scheduling priority of a process
• top: Monitor process priorities and CPU usage

Related Commands

• nice
• renice
• ps