# Amazon Web Services (AWS) Monitoring Tools - Applications Manager User Guide

## Amazon DocumentDB Monitoring

## Overview

Amazon DocumentDB (with MongoDB compatibility) is a fully managed, scalable document database service that supports MongoDB workloads. Applications Manager monitors three types of DocumentDB resources:

- [DocumentDB Cluster](#cluster) - Consists of a primary instance and up to 15 read replicas across multiple Availability Zones, backed by a distributed storage system that automatically scales.
- [DocumentDB Global Cluster](#global-cluster) - Spans multiple AWS Regions, enabling low-latency global reads and disaster recovery from Region-wide outages.
- [DocumentDB Instance](#instance) - The compute components within a DocumentDB cluster that run the database engine and manage data processing for read and write operations.

## Creating new DocumentDB monitors

To learn how to create new DocumentDB monitors, [refer here](https://www.manageengine.com/products/applications_manager/help/aws-monitoring-tools.html#NewMonitor).

## DocumentDB Cluster

Applications Manager's DocumentDB Cluster monitoring tool provides visibility into the performance, CPU utilization, memory usage, replication lag, database operations, network throughput, and storage metrics of your DocumentDB clusters. Monitoring these metrics enables administrators to identify performance bottlenecks, optimize resource allocation, and ensure high availability of their document database workloads.

### Monitored parameters

Go to the **Monitors Category View** by clicking the **Monitors** tab. Click on the **DocDB Cluster** instance available under **Amazon** in the **Cloud Apps** section. Displayed is the DocDB Cluster bulk configuration view distributed into three tabs:

- **Availability** tab shows the availability history for the past 24 hours or 30 days.
- **Performance** tab shows health status and events for the past 24 hours or 30 days.
- **List view** tab enables you to perform [bulk admin configurations](https://www.manageengine.com/products/applications_manager/help/bulk-config.html).

By clicking a monitor from the list, you will be taken to the Amazon DocumentDB Cluster dashboard which includes the following tabs:

- [Performance Overview](#cluster-performance-overview)
- [DB Operations](#cluster-db-operations)
- [Network & Storage](#cluster-network-storage)
- [NVMe Storage](#cluster-nvme-storage)
- [Configuration](#cluster-configuration)

### Performance Overview

| Parameter | Description |
|---|---|
| **CLUSTER INFORMATION** |  |
| Cluster Status | The current status of the DocumentDB resource. |
| Endpoint | The endpoint for the primary instance of the cluster. |
| Cluster Reader Endpoint | The reader endpoint for the resource. |
| Cluster Port | The port on which the resource listens. |
| Engine Uptime | The maximum time taken by the DocumentDB resource to run at the time of polling (in minutes). |
| Available MVCC IDs | The average number of Multi-Version Concurrency Control (MVCC) IDs available in the DocumentDB resource at the time of polling. |
| Longest Active GC Runtime | The average duration of the longest active garbage collection operation on the DocumentDB resource between the poll interval (in seconds). |
| **CPU UTILIZATION** |  |
| CPU Utilization | The average percentage of CPU used by the DocumentDB resource at the time of polling (in %). |
| **BUFFER CACHE HIT RATIO** |  |
| Buffer Cache Hit Ratio | The average percentage of requests served by the buffer cache on the DocumentDB resource between the poll interval (in %). |
| Index Buffer Cache Hit Ratio | The average percentage of index requests served by the buffer cache on the DocumentDB resource between the poll interval (in %). |
| **CPU CREDITS** |  |
| CPU Credit Balance | The average number of CPU credits available for the DocumentDB resource instance to burst beyond its base CPU utilization at the time of polling. |
| CPU Credit Usage | The average number of CPU credits consumed by the DocumentDB resource instance at the time of polling. |
| **CPU SURPLUS CREDIT BALANCE & CHARGES** |  |
| CPU Surplus Credit Balance | The average number of surplus CPU credits spent to sustain CPU performance when the CPUCreditBalance value is zero at the time of polling. |
| CPU Surplus Credits Charged | The average number of surplus CPU credits exceeding the maximum number of CPU credits that can be earned in a 24-hour period, and thus attracting an additional charge, measured for the DocumentDB resource between the poll interval. |
| **FREE MEMORY** |  |
| Free Memory | The average amount of available random access memory of the DocumentDB resource at the time of polling (in MB). |
| **SWAP USAGE** |  |
| Swap Usage | The average amount of swap space used on the DocumentDB resource at the time of polling (in MB). |
| **LOW MEMORY OPERATIONS THROTTLED** |  |
| Operations Throttled (Low Memory) | The total number of requests that are throttled due to low available memory on the DocumentDB resource between the poll interval. |
| **LOW MEMORY THROTTLING** |  |
| Queue Depth (Low Memory Throttled Requests) | The total queue depth for requests that are throttled due to low available memory on the DocumentDB resource between the poll interval. |
| Max Queue Depth (Low Memory Throttled Requests) | The maximum queue depth for requests that are throttled due to low available memory on the DocumentDB resource between the poll interval. |
| **LATENCY** |  |
| Read Latency | The average time taken per disk IO read operation on the DocumentDB resource during the polling interval (in ms). |
| Write Latency | The average time taken per disk IO write operation on the DocumentDB resource during the polling interval (in ms). |
| **REPLICATION LAG** |  |
| Replication Lag | The average amount of lag when replicating updates from the primary instance to a replica instance on the DocumentDB resource between the poll interval (in ms). |
| Replica Lag (Max) | The maximum amount of lag between the primary instance and each DocumentDB instance in the cluster between the poll interval (in ms). |
| Replica Lag (Min) | The minimum amount of lag between the primary instance and each DocumentDB instance in the cluster between the poll interval (in ms). |

### DB Operations

| Parameter | Description |
|---|---|
| **DATABASE CONNECTIONS** |  |
| Database Connections | The average number of database connections in use on the DocumentDB resource between the poll interval. |
| Database Connections Limit | The maximum database connections limit on the DocumentDB resource between the poll interval. |
| Database Connections Max | The maximum number of open database connections on the DocumentDB resource between the poll interval. |
| **DATABASE CURSORS** |  |
| Database Cursors | The average number of cursors open on the DocumentDB resource between the poll interval. |
| Database Cursors Limit | The maximum database cursors limit on the DocumentDB resource between the poll interval. |
| Database Cursors Max | The maximum number of open cursors on the DocumentDB resource between the poll interval. |
| **DATABASE CURSORS TIMED OUT** |  |
| Database Cursors Timed Out | The total number of cursors that timed out on the DocumentDB resource between the poll interval. |
| **TRANSACTIONS OPEN** |  |
| Transactions Open | The average number of transactions currently open on the DocumentDB resource between the poll interval. |
| Transactions Open Limit | The maximum limit of open transactions on the DocumentDB resource between the poll interval. |
| Transactions Open Max | The maximum number of open transactions on the DocumentDB resource between the poll interval. |
| **TRANSACTIONS** |  |
| Transactions Started | The total number of transactions started on the DocumentDB resource between the poll interval. |
| Transactions Committed | The total number of transactions committed on the DocumentDB resource between the poll interval. |
| Transactions Aborted | The total number of transactions aborted on the DocumentDB resource between the poll interval. |
| **DOCUMENT OPERATIONS** |  |
| Documents Updated | The total number of documents updated on the DocumentDB resource between the poll interval. |
| Documents Deleted | The total number of documents deleted from the DocumentDB resource between the poll interval. |
| Documents Inserted | The total number of documents inserted into the DocumentDB resource between the poll interval. |
| Documents Returned | The total number of documents returned by queries on the DocumentDB resource between the poll interval. |
| **DATABASE OPERATIONS - READ** |  |
| Query Operations | The total number of query operations issued on the DocumentDB resource between the poll interval. |
| Cursor Fetch Operations | The total number of getmore operations issued on the DocumentDB resource between the poll interval. |
| Commands Issued | The total number of commands issued on the DocumentDB resource between the poll interval. |
| **DATABASE OPERATIONS - WRITE** |  |
| Insert Operations | The total number of insert operations issued on the DocumentDB resource between the poll interval. |
| Update Operations | The total number of update operations issued on the DocumentDB resource between the poll interval. |
| Delete Operations | The total number of delete operations issued on the DocumentDB resource between the poll interval. |
| **DOCUMENTS DELETED BY TTL** |  |
| Documents Deleted by TTL | The total number of documents deleted by a TTL index on the DocumentDB resource between the poll interval. |

`Note: DB Operations tab metrics are disabled from data collection by default and mapped under performance polling as DB Operations. To enable data collection, navigate to Settings → Performance Polling, select the Optimize Data Collection tab, choose Amazon DocumentDB Cluster as the monitor type and DB Operations as the metric name, then set the preferred time interval.`