I want to use Amazon CloudWatch to monitor my Amazon Elastic File System (Amazon EFS) metrics. How can I do this?

## Short description

Amazon EFS automatically sends metric data to CloudWatch in one-minute intervals. The data is recorded for a 15-month period so that you can get a better insight on your application's file system usage.

You can monitor the various CloudWatch metrics for bench-marking, scaling, and monitoring purposes.

## Resolution

To calculate the average throughput, IOPS, or throughput percentage of your file system, create a metric math expression using the **TotalIOByte** metric. To create the metric math expression, do the following:

- Open the CloudWatch console.
- Select
**Metric**, **All metrics**.
- Select
**EFS file system metrics**.
- Select the metric
**TotalIOBytes** and then select **Graphed metrics**.
- Choose
**Sum** from the **Statistics** drop down menu.
- Select
**Add math**, **Start with empty expression**.
- Add one of the following formulas in the expression
**e1** to calculate throughput or IOPS:

**Calculate throughput in MiB/second:**

Formula for calculating throughput: **TotalIOBytes ÷ 1,048,576 (to convert to MiB) ÷ seconds in the period**.

Enter the following expression: **(m1/1048576)/PERIOD(m1)**.

The expression appears as **e1=(m1/1048576)/PERIOD(m1)**.

**e1** is throughput in **MiB/**s, m1 is **TotalIOBytes**. The **TotalIObytes** is divided by 1048576 to convert it to MiB.

**Note:** To calculate read, write, or metadata throughput specifically, replace the **TotalIOByte** in the preceding expression with **DataReadIOBytes**, **DataWriteIOBytes**, or **MetadataIOBytes**.

**Calculate IOPS (average operations per second):**

Formula for calculating IOPS: **TotalIOBytes ÷ seconds in the period**.

Enter the following expression: **m1/PERIOD(m1)**.

The expression appears as **e1=m1/PERIOD(m1)**.

**e1** is **IOPS**, **m1** is **TotalIOBytes**.

**Note:** To calculate read, write, or metadata IOPS specifically, replace **TotalIOByte** in the preceding expression with **DataReadIOBytes**, **DataWriteIOBytes**, or **MetadataIOBytes**.

For more information, see Using metric math with Amazon EFS.

## Related information

CloudWatch metrics for Amazon EFS