[Linux] C Shell (csh) iotop用法: Monitor disk I/O usage by processes

Overview

The iotop command is a powerful tool that allows users to monitor disk I/O usage by processes in real-time. It provides a dynamic view of which processes are consuming the most disk resources, helping to identify bottlenecks and optimize system performance.

Usage

The basic syntax of the iotop command is as follows:

iotop [options] [arguments]

Common Options

-o, --only: Show only processes or threads actually doing I/O, which can help focus on active processes.
-b, --batch: Run in batch mode, useful for logging output to a file.
-n NUM, --iter NUM: Set the number of iterations before exiting.
-d SEC, --delay SEC: Set the delay between updates in seconds.

Common Examples

Here are some practical examples of using iotop:

Basic Usage: Launch iotop to view real-time disk I/O.
```
iotop
```
Show Only Active Processes: Display only the processes that are currently performing I/O.
```
iotop -o
```
Batch Mode for Logging: Run iotop in batch mode and log the output to a file for later analysis.
```
iotop -b -n 10 > iotop_log.txt
```
Set Update Interval: Change the update interval to 2 seconds.
```
iotop -d 2
```
Limit Iterations: Run iotop for a specific number of iterations, e.g., 5.
```
iotop -n 5
```

Tips

Use iotop with root privileges to ensure you can see all processes and their I/O usage.
Combine iotop with other monitoring tools like top or htop for a comprehensive view of system performance.
Regularly check for processes with high I/O usage to maintain optimal system performance and prevent slowdowns.