# Read server graphs

Follow a server's CPU, memory, disk and network use over the last hour, day or week, so you can spot a full disk or a busy server before it causes trouble.

## Before you start

- A running server in Nuvlo. See [Create a server](https://app.nuvlo.dev/docs/create-a-server).

## Step 1: Open the Graphs tab

Open [Servers](https://app.nuvlo.dev/dashboard/servers), click the server and select the **Graphs** tab.

The server's **Overview** tab shows the same values live. This tab shows how they changed over time.

## Step 2: Pick a time range

Choose **Live**, **1 hour**, **12 hours**, **24 hours** or **1 week** at the top right. All charts switch to that range.

![The Graphs tab of a server with the time range buttons and the CPU, RAM and disk charts](https://app.nuvlo.dev/docs/shots/server-graphs--graphs.webp)

## Step 3: Read the charts

| Chart | What it shows |
| --- | --- |
| **CPU usage** | How busy the processor is, in percent. |
| **RAM usage** | How much memory is in use, in percent. |
| **Disk usage** | How full the disk is, in percent. |
| **Disk throughput** | How much data is read from and written to the disk. |
| **Disk IOPS** | How many read and write operations the disk handles. |
| **Network traffic** | Data coming in and going out. |
| **Network packets per second** | Packets coming in and going out. |

![All server charts for the last 24 hours: CPU, RAM and disk usage, disk throughput and IOPS, network traffic and packets](https://app.nuvlo.dev/docs/shots/server-graphs--charts.webp)

CPU or RAM that stays near 100% means the server is too small for its sites. You can [resize the server](https://app.nuvlo.dev/docs/resize-a-server). A disk that keeps filling up also shows as an alert on the [Monitoring](https://app.nuvlo.dev/docs/monitoring) page once it passes 85%.

## If the charts stay empty

The server reports its values through a small monitoring agent. If you see **Collecting historical metrics**, the first samples haven't arrived yet. Wait a few minutes, or click **Refresh agent** to reinstall the agent and reload the charts.

History is kept for one week. Values older than a day are shown as 15-minute averages.

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Source: https://app.nuvlo.dev/docs/server-graphs