Review Available Metrics
You can review the following metrics to monitor your deployments. All hardware metrics include metrics or individual charts for maximum values.
Note
Ops Manager can only collect hardware metrics if you have enabled an automation agent. A monitoring agent can only collect database metrics.
Important
The metrics available depend on your user role and deployment type.
Metric | Description |
---|---|
Asserts | Displays the following information:
Monitor asserts to track how many errors occur while trying to read or write data. Check the server logs to identify the source of any errors. |
Avg Object Size | Displays the average object size across all collections in the database. Monitor object size to track the size of your objects and better understand your database space. |
Background Flush Avg | Displays the average time of background flushes in seconds.
Monitor the background flush average to determine whether this statistic is a significant percentage of 60 seconds. If so, this statistic could indicate that the server is bottlenecked on these writes. You might have a large number of random writes occurring. The operating system might flush data faster than every 60 seconds. In that case, this statistic will be a very small value even if the writing is a bottleneck. |
Collections | Displays the number of collections in the database. Monitor collections to determine restart times, continuous backup performance, and stability. |
Connections | Displays the total number of active connections to the deployment. Monitor connections to determine whether the current connection limits are sufficient. |
Cursors | Displays the following information:
Monitor cursors to close unnecessary cursors and reduce the timeout configuration in the application. |
Data Size | Displays the actual size of the data files in the database. Monitor data size to ensure that database is not using too much memory or CPU. |
DB Storage | Displays the following information:
Monitor storage space to determine whether to manually increase the disk size. |
Disk IOPS | Displays input operations per second. Monitor whether disk IOPS approaches the maximum provisioned IOPS. Determine whether the deployment can handle future workloads. |
Disk Latency | Displays the following information:
Monitor disk latency to track the efficiency of reading from and writing to disk. |
Disk Queue Depth | Displays the average length of the queue of requests issued to the disk partition that stores MongoDB data. Monitor disk queue depth to identify potential issues and bottlenecks. |
Disk Space Free | Displays the total amount of free space remaining on disk. Monitor free disk space to determine whether to use disk auto-scaling or manually increase the disk size. |
Disk Space Percent Free | Displays the total amount of free space remaining on disk as a percentage of the total disk space. Monitor the percentage of free disk space to determine whether to use disk auto-scaling or manually increase the disk size. |
Disk Space Used | Displays the total bytes of used disk space on the partition that runs MongoDB. Monitor the used disk space to determine whether to manually increase the disk size. |
Document Metrics | Displays the following information:
Monitor document metrics to measure the work MongoDB completes. |
File Size | Displays the total size of all the data files in the database. Monitor file size to deternine whether files are consuming excessive disk space. |
Index Size | Displays the total size of all indexes in the database. This metric includes the overhead incurred by indexes on top of the actual document data on which the indexes are based. Monitor the index size to manage your indexes. To learn more, see Indexing Strategies. |
Indexes | Displays the total number of indexes in the database. Monitor indexes to manage them. To learn more, see Indexing Strategies. |
Max Disk IOPS | Displays the following maximum disk IOPS values over the time period specified by the metric granularity:
Monitor whether disk IOPS approaches the maximum provisioned IOPS. Determine whether the deployment can handle future workloads. |
Max Disk Queue Depth | Displays the maximum disk queue depth values over the time period specified by the metric granularity. Disk queue depth is the average length of the queue of requests issued to the disk partition that stores MongoDB data. Monitor disk queue depth to identify potential issues and bottlenecks. |
Max Normalized System CPU | Displays the maximum CPU usage values of all processes on the node, scaled to a range of 0-100% by dividing by the number of CPU cores. Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Max Process CPU | Displays the following maximum process CPU values over the time period specified by the metric granularity:
Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Max System CPU | Displays the maximum CPU usage values of all processes on the node. Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Max System Memory | Displays the maximum system memory values in bytes. Monitor memory to determine whether your currrent deployment meets your memory needs. |
Memory | Displays the total consumption of memory in megabytes at a particular point in time:
Monitor memory to determine whether your currrent deployment meets your memory needs. |
Network | Displays the following information:
Monitor network metrics to track network performance. |
Non-Mapped Virtual Memory | Displays the amount of virtual memory that the memory mapping of data files doesn't take into account. Monitor non-mapped virtual memory to determine whether aspects other than memory mapping files use excessive memory. For example, this could indicate too many connections to the database. Each connection has a thread stack and the memory for those stacks can add up to a considerable amount. Keep this statistic reasonably low because the memory used here is unavailable for caching. |
Normalized Process CPU | Displays the following information:
Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Normalized System CPU | Displays the CPU usage of all processes on the node, scaled to a range of 0-100% by dividing by the number of CPU cores. Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Num Extents | Displays the total number of contiguously allocated chunks of data file space for the database. Monitor this metric to better understand your database space. |
Objects | Displays the number of objects in the database. Monitor this metric to better understand your database space. |
OpCounters | Displays the number of the following operations per second run on a MongoDB process since the process last started:
Monitor MongoDB operations to validate performance issues related to high workloads. Confirm the type of operations responsible for the load. |
Page Faults | Displays the average rate of page faults on this process per second over the selected sample period. In non-Windows environments this applies to hard page faults only. Monitor page faults to determine whether to increase your memory. |
Process CPU | Displays the following information:
Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |
Queues | Displays the following information:
Monitor queues to identify potential issues and bottlenecks. |
Query Targeting | Displays the following information:
Monitor query targeting to determine whether you have any inefficient queries. |
Query Targeting | Displays the efficiency of read operations run on MongoDB:
Monitor query targeting to determine read efficiency and optimize queries and indexes. |
Scan and Order | Displays the number of operations per second returning results that required a sort in-memory. Monitor this metric to identify whether your queries need indexes. |
Shard Data Size | Displays the amount of storage space in bytes that your stored data uses on each shard. You can access this chart only for sharded clusters with MongoDB 6.0+. Monitor this metric to verify whether you have balanced shards. |
Shard Document Count | Displays the number of documents on each shard. You can access this chart only for sharded clusters with MongoDB 6.0+. Monitor this metric to verify whether you have balanced shards. |
Storage Size | Displays the storage size of the database. Monitor storage size to determine whether to manually increase the disk size. |
System CPU | Displays the CPU usage of all processes on the node. Monitor CPU usage to determine whether data is retrieved from disk instead of memory. |