---
title: "Monitoring Your Server with htop"
source: "https://docs.nexcess.com/hosting/performance/server-optimization/monitoring-your-server-with-htop/"
description: "htop: Your server's intuitive monitor. See CPU/memory, processes, and troubleshoot with interactive sorting, filtering, and direct process management."
vertical: "Hosting"
date: "2025-05-27"
last_modified: "2026-07-30"
---

# Monitoring Your Server with htop

Keeping an eye on your server’s performance is crucial for maintaining stability and quickly troubleshooting issues. While `top` is a well-known tool, `htop` offers a more user-friendly and powerful way to monitor your system and processes. Think of `htop` as an enhanced version of `top`, providing a clearer, more interactive view of what’s happening on your server.

##### Why htop?

*htop* makes system monitoring easier by:

- Presenting information in a more readable, colorful layout.
- Allowing you to scroll through and sort the process list.
- Enabling you to send signals (like `kill`) to processes directly from the interface.
- Showing you precisely how much physical memory applications are using, excluding buffer and cache memory.

##### Installing htop (YUM)

If `htop` isn’t already on your server, you can usually install it from the EPEL (Extra Packages for Enterprise Linux) repository.

- **Install EPEL Release (if needed):**` `

```
yum -y install epel-release
```

- **Install htop:**

```
yum -y install htop
```

If you encounter an error like “No package htop available,” check your `/etc/yum.repos.d/epel.repo` file to ensure the EPEL repository is enabled.

- If you installed EPEL just for `htop` and don’t need it for other software, it’s generally safe to remove the `epel-release` package after `htop` is installed:

```
yum remove epel-release
```

##### How to use htop?

Once `htop` is running (just type `htop` in your terminal and press Enter), you’ll see a dynamic, real-time display of your server’s activity.

##### CPU and memory usage :

![](https://docs.nexcess.com/wp-content/uploads/2026/06/image-7-1024x246-1.png)At the top of the `htop` display, you’ll see multiple numbered bars with colorful segments.

- **CPU Cores:** Each bar represents a CPU core on your server. The number of bars corresponds to the number of cores your CPU has. The colors within each bar indicate the type of load: 
    - **Blue:** Low-priority processes.
    - **Green:** Normal user processes (applications you run).
    - **Red:** Kernel processes (core operating system tasks).
- **Memory (Mem) and Swap (Swp):** Below the CPU bars, these rows show your server’s memory usage. The colors within these bars represent: 
    - **Green:** Memory actively used by running programs.
    - **Blue:** Memory used for buffers (temporary storage for disk I/O).
    - **Yellow:** Memory used for cache (recently accessed data from disk, speeding up future access).

#### Tasks, system load averages, and uptime

![](https://docs.nexcess.com/wp-content/uploads/2026/06/image-8.png)Next to the memory bars, you’ll find key system statistics:

- **Tasks:** This shows the number of active processes on your system. It typically displays three values: the total number of processes, the number of threads within those processes, and how many tasks are currently running.
- **Load Average:** This measures the computational work your CPU is handling. It’s a key indicator of how busy your server is. 
    - A single-core CPU at 100% utilization would have a 1.0 load average.
    - A quad-core CPU at 100% utilization would have a 4.0 load average.
    - You’ll see three numbers: the average load over the last one minute, five minutes, and fifteen minutes.
- **Uptime:** This tells you how long your system has been running continuously since its last reboot.

#### Process information 

![](https://docs.nexcess.com/wp-content/uploads/2026/06/image-9-1024x275-1.png)The main part of the `htop` screen is a list of all running processes. Each column provides specific details:

- **PID:** The unique Process ID number.
- **USER:** The user account that owns the process.
- **PRI:** The process’s priority as set by the kernel.
- **NI:** The “nice” value, which is the process priority adjusted by a user or root.
- **VIRT:** The total virtual memory the process is using.
- **RES:** The actual physical memory (RAM) the process is consuming.
- **SHR:** The amount of shared memory the process is using.
- **S:** The current state of the process (e.g., `R` for running, `S` for sleeping).
- **CPU%:** The percentage of CPU resources the process is currently using.
- **MEM%:** The percentage of total physical memory the process is consuming.
- **TIME+:** The total CPU time the process has used since it started.
- **Command:** The name of the command or program that started the process.

#### Footer menu commands

At the bottom of the `htop` screen, you’ll see a row of function key commands (F1 through F10) that provide quick access to common actions:

- **F2 Setup:** Tweak `htop`‘s display options, columns, and colors.
- **F3 Search:** Find specific processes by name.
- **F4 Filter:** Apply filters to narrow down the displayed processes.
- **F5 Tree:** View processes in a hierarchical tree structure, showing parent-child relationships.
- **F6 SortBy:** Change the sorting order of processes (e.g., by CPU usage, memory usage).
- **F9 Kill:** Send a signal to the currently highlighted process (e.g., to stop it).
- **F10 Quit:** Exit `htop`.

#### Useful shortcut keys

To become even more efficient with `htop`, try these keyboard shortcuts:

- **u:** Display all processes owned by a particular user (you’ll be prompted to select a user).
- **p:** Sort processes by high CPU consumption.
- **m:** Sort processes by high memory consumption.
- **t:** Sort processes by the total time they’ve been running.
- **Space:** “Tag” a process. You can tag multiple processes and then perform actions on all tagged processes at once.
- **c:** Tag a process and all its child processes.
- **Shift + u:** Remove all tags.
- **Shift + f:** Highlight and “follow” a process. If the process moves in the list due to sorting, `htop` will keep it in view.
- **Shift + h:** Toggle showing/hiding user and kernel processes.
- **a:** Set what CPU cores a process can access (affinity).
- **i:** Set a process’s I/O priority.
- **h:** Display the `htop` help menu.

### Conclusion

`htop` is an indispensable tool for anyone managing a Linux server. Its intuitive interface and powerful features make it easy to monitor performance, identify resource-intensive processes, and troubleshoot issues quickly. By familiarizing yourself with `htop`, you’ll gain a deeper understanding and better control over your server’s health. As always, if you have questions or need assistance, contact our [Support team](https://docs.nexcess.com/sites-stores/support/).