# Identify your unused resources to optimize costs in Amazon Keyspaces
This section provides an overview of how to evaluate your unused resources regularly. As your application requirements evolve, you should ensure no resources are unused and contributing to unnecessary Amazon Keyspaces costs. The procedures described below use Amazon CloudWatch metrics to identify unused resources and take action to reduce costs.
You can monitor Amazon Keyspaces using CloudWatch, which collects and processes raw data from Amazon Keyspaces into readable, near real-time metrics. These statistics are retained for a period of time, so that you can access historical information to better understand your utilization. By default, Amazon Keyspaces metric data is sent to CloudWatch automatically. For more information, see [What is Amazon CloudWatch?](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/WhatIsCloudWatch.html) and [Metrics retention](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch_concepts.html#metrics-retention) in the *Amazon CloudWatch User Guide*.
**Topics**
+ [How to identify unused resources](#CostOptimization_UnusedResources_Identifying)
+ [Identifying unused table resources](#CostOptimization_UnusedResources_Tables)
+ [Cleaning up unused table resources](#CostOptimization_UnusedResources_Tables_Cleanup)
+ [Cleaning up unused point-in-time recovery (PITR) backups](#CostOptimization_UnusedResources_Backups)
## How to identify unused resources
To identify unused tables you can take a look at the following CloudWatch metrics over a period of 30 days to understand if there are any active reads or writes on a specific table:
**`ConsumedReadCapacityUnits`**
The number of read capacity units consumed over the specified time period, so you can track how much consumed capacity you have used. You can retrieve the total consumed read capacity for a table.
**`ConsumedWriteCapacityUnits`**
The number of write capacity units consumed over the specified time period, so you can track how much consumed capacity you have used. You can retrieve the total consumed write capacity for a table.
## Identifying unused table resources
Amazon CloudWatch is a monitoring and observability service which provides the Amazon Keyspaces table metrics you can use to identify unused resources. CloudWatch metrics can be viewed through the AWS Management Console as well as through the AWS Command Line Interface.
------
#### [ AWS Command Line Interface ]
To view your tables metrics through the AWS Command Line Interface, you can use the following commands.
1. First, evaluate your table's reads:
**Note**
If the table name is not unique within your account, you must also specify the name of the keyspace.
```
aws cloudwatch get-metric-statistics --metric-name
ConsumedReadCapacityUnits --start-time --end-time --period --namespace AWS/Cassandra --statistics Sum --
dimensions Name=TableName,Value=
```
To avoid falsely identifying a table as unused, evaluate metrics over a longer period. Choose an appropriate start-time and end-time range, such as ** 30 days**, and an appropriate period, such as **86400**.
In the returned data, any **Sum** above **0** indicates that the table you are evaluating received read traffic during that period.
The following result shows a table receiving read traffic in the evaluated period:
```
{
"Timestamp": "2022-08-25T19:40:00Z",
"Sum": 36023355.0,
"Unit": "Count"
},
{
"Timestamp": "2022-08-12T19:40:00Z",
"Sum": 38025777.5,
"Unit": "Count"
},
```
The following result shows a table not receiving read traffic in the evaluated period:
```
{
"Timestamp": "2022-08-01T19:50:00Z",
"Sum": 0.0,
"Unit": "Count"
},
{
"Timestamp": "2022-08-20T19:50:00Z",
"Sum": 0.0,
"Unit": "Count"
},
```
1. Next, evaluate your table’s writes:
```
aws cloudwatch get-metric-statistics --metric-name
ConsumedWriteCapacityUnits --start-time --end-time --period --namespace AWS/Cassandra --statistics Sum --
dimensions Name=TableName,Value=
```
To avoid falsely identifying a table as unused, you will want to evaluate metrics over a longer period. Choose an appropriate start-time and end-time range, such as **30 days**, and an appropriate period, such as **86400**.
In the returned data, any **Sum** above **0** indicates that the table you are evaluating received read traffic during that period.
The following result shows a table receiving write traffic in the evaluated period:
```
{
"Timestamp": "2022-08-19T20:15:00Z",
"Sum": 41014457.0,
"Unit": "Count"
},
{
"Timestamp": "2022-08-18T20:15:00Z",
"Sum": 40048531.0,
"Unit": "Count"
},
```
The following result shows a table not receiving write traffic in the evaluated period:
```
{
"Timestamp": "2022-07-31T20:15:00Z",
"Sum": 0.0,
"Unit": "Count"
},
{
"Timestamp": "2022-08-19T20:15:00Z",
"Sum": 0.0,
"Unit": "Count"
},
```
------
#### [ AWS Management Console ]
The following steps allow you to evaluate your resource utilization through the AWS Management Console.
1. Log into the AWS Management Console and navigate to the CloudWatch service page at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/). Select the appropriate AWS Region in the top right of the console, if necessary.
1. On the left navigation bar, locate the **Metrics** section and choose **All metrics**.
1. The action above opens a dashboard with two panels. In the top panel, you can see currently graphed metrics. On the bottom you can select the metrics available to graph. Choose Amazon Keyspaces in the bottom panel.
1. In the Amazon Keyspaces metrics selection panel, choose the **Table Metrics** category to show the metrics for your tables in the current region.
1. Identify your table name by scrolling down the menu, then choose the metrics `ConsumedReadCapacityUnits` and `ConsumedWriteCapacityUnits` for your table.
1. Choose the **Graphed metrics (2)** tab and adjust the **Statistic** column to **Sum**.
1. To avoid falsely identifying a table as unused, evaluate the table metrics over a longer period. At the top of the graph panel, choose an appropriate time frame, such as 1 month, to evaluate your table. Choose **Custom**, choose **1 Months** in the drop-down menu, and choose **Apply**.
1. Evaluate the graphed metrics for your table to determine if it is being used. Metrics that have gone above **0** indicate that a table has been used during the evaluated time period. A flat graph at **0** for both read and write indicates that a table is unused.
------
## Cleaning up unused table resources
If you have identified unused table resources, you can reduce their ongoing costs in the following ways.
**Note**
If you have identified an unused table but would still like to keep it available in case it needs to be accessed in the future, consider switching it to on-demand mode. Otherwise, you can consider deleting the table.
**Capacity modes**
Amazon Keyspaces charges for reading, writing, and storing data in your Amazon Keyspaces tables.
Amazon Keyspaces has [two capacity modes](ReadWriteCapacityMode.md), which come with specific billing options for processing reads and writes on your tables: on-demand and provisioned. The read/write capacity mode controls how you are charged for read and write throughput and how you manage capacity.
For on-demand mode tables, you don't need to specify how much read and write throughput you expect your application to perform. Amazon Keyspaces charges you for the reads and writes that your application performs on your tables in terms of read request units and write request units. If there is no activity on your table, you do not pay for throughput but you still incur a storage charge.
**Deleting tables**
If you’ve discovered an unused table and would like to delete it, consider to make a backup or export the data first.
Backups taken through AWS Backup can leverage cold storage tiering, further reducing cost. Refer to the [Managing backup plans](https://docs.aws.amazon.com/aws-backup/latest/devguide/about-backup-plans) documentation for information on how to use a lifecycle to move your backup to cold storage.
After your table has been backed up, you may choose to delete it either through the AWS Management Console or through the AWS Command Line Interface.
## Cleaning up unused point-in-time recovery (PITR) backups
Amazon Keyspaces offers Point-in-time recovery, which provides continuous backups for 35 days to help you protect against accidental writes or deletes. PITR backups have costs associated with them.
Refer to the documentation at [Backup and restore data with point-in-time recovery for Amazon Keyspaces](PointInTimeRecovery.md) to determine if your tables have backups enabled that may no longer be needed.