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Host Metrics

  • ASSERT_REGULAR

  • ASSERT_WARNING

  • ASSERT_MSG

  • ASSERT_USER

Measures the rate of asserts for a MongoDB process, as collected from the MongoDB serverStatus command's asserts document.
  • BACKGROUND_FLUSH_AVG

Amount of data flushed in the background.
  • CACHE_BYTES_READ_INTO

  • CACHE_BYTES_WRITTEN_FROM

Applies to a MongoDB process's WiredTiger storage engine, as collected from the MongoDB serverStatus command's wiredTiger.cache and queues.execution documents.
  • CACHE_DIRTY_BYTES

  • CACHE_USED_BYTES

Total dirty or used bytes cached in memory for serving reads and writes.
  • CONNECTIONS

  • SERVERLESS_CONNECTIONS

  • CONNECTIONS_PERCENT

  • SERVERLESS_CONNECTIONS_PERCENT

Measures connections to a MongoDB process, as collected from the MongoDB serverStatus command's connections document.
  • CURSORS_TOTAL_OPEN

  • CURSORS_TOTAL_TIMED_OUT

  • CURSORS_TOTAL_CLIENT_CURSORS_SIZE

Measures the number of cursors for a MongoDB process, as collected from the MongoDB serverStatus command's metrics.cursor document.
  • DB_DATA_SIZE_TOTAL

  • SERVERLESS_DATA_SIZE_TOTAL

Sum total of the uncompressed document data in bytes across all databases, including system databases.
  • DB_STORAGE_TOTAL

Sum total of the compressed on-disk storage space allocated for document storage across all databases.

Atlas retrieves database metrics every 20 minutes by default but adjusts frequency when necessary to reduce the impact on database performance.

  • DB_INDEX_SIZE_TOTAL

Sum total of the logical size in bytes (including prefix compression) of the index data across all databases.
  • DB_DATA_SIZE_TOTAL_WO_SYSTEM

Sum total of the uncompressed document data in bytes across non-system databases.
  • LOGICAL_SIZE

Logical size of cluster data.
  • DISK_PARTITION_SPACE_USED_DATA

  • DISK_PARTITION_READ_IOPS_DATA

  • DISK_PARTITION_WRITE_IOPS_DATA

  • DISK_PARTITION_READ_LATENCY_DATA

  • DISK_PARTITION_WRITE_LATENCY_DATA

Partition measurements for different types of MongoDB data.
  • MAX_DISK_PARTITION_SPACE_USED_DATA

  • MAX_DISK_PARTITION_READ_IOPS_DATA

  • MAX_DISK_PARTITION_WRITE_IOPS_DATA

  • MAX_DISK_PARTITION_READ_LATENCY_DATA

  • MAX_DISK_PARTITION_WRITE_LATENCY_DATA

Maximum values for partition measurements for different types of MongoDB data.
  • DISK_PARTITION_QUEUE_DEPTH_DATA

Average length of the queue of requests issued to the disk partition that MongoDB uses.
  • MAX_DISK_PARTITION_QUEUE_DEPTH_DATA

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 MongoDB uses.
  • DOCUMENT_RETURNED

  • DOCUMENT_INSERTED

  • DOCUMENT_UPDATED

  • DOCUMENT_DELETED

Average rate per second of documents returned, inserted, updated, or deleted for a selected time period.
  • EXTRA_INFO_PAGE_FAULTS

  • GLOBAL_ACCESSES_NOT_IN_MEMORY

  • GLOBAL_PAGE_FAULT_EXCEPTIONS_THROWN

Measurements on page faults related to the host.
  • FTS_MEMORY_RESIDENT

  • FTS_MEMORY_VIRTUAL

  • FTS_MEMORY_SHARED

  • FTS_CURRENT_MEMORY

  • FTS_MAX_MEMORY

Memory usage for Atlas Search processes, in bytes.
  • FTS_PROCESS_CPU_USER

  • FTS_PROCESS_CPU_KERNEL

  • FTS_PROCESS_DISK

  • NORMALIZED_FTS_PROCESS_CPU_USER

  • NORMALIZED_FTS_PROCESS_CPU_KERNEL

Percentage of CPU in use by Atlas Search processes.
  • GLOBAL_LOCK_CURRENT_QUEUE_TOTAL

  • GLOBAL_LOCK_CURRENT_QUEUE_READERS

  • GLOBAL_LOCK_CURRENT_QUEUE_WRITERS

  • GLOBAL_LOCK_PERCENTAGE

Measures operations waiting on locks, as collected from the MongoDB serverStatus command.
  • INDEX_COUNTERS_BTREE_ACCESSES

  • INDEX_COUNTERS_BTREE_HITS

  • INDEX_COUNTERS_BTREE_MISSES

  • INDEX_COUNTERS_BTREE_MISS_RATIO

Measurements concerning B-tree index activity.
  • JOURNALING_COMMITS_IN_WRITE_LOCK

  • JOURNALING_MB

  • JOURNALING_WRITE_DATA_FILES_MB

Measurements concerning journaling activity.
  • MEMORY_RESIDENT

  • MEMORY_VIRTUAL

  • MEMORY_MAPPED

  • COMPUTED_MEMORY

Measures memory for a MongoDB process, as collected from the MongoDB serverStatus command's mem document.
  • MUNIN_CPU_USER

  • MUNIN_CPU_NICE

  • MUNIN_CPU_SYSTEM

  • MUNIN_CPU_IOWAIT

  • MUNIN_CPU_IRQ

  • MUNIN_CPU_SOFTIRQ

  • MUNIN_CPU_STEAL

  • NETWORK_BYTES_IN

  • NETWORK_BYTES_OUT

  • NETWORK_NUM_REQUESTS

  • SERVERLESS_NETWORK_BYTES_IN

  • SERVERLESS_NETWORK_BYTES_OUT

  • SERVERLESS_NETWORK_NUM_REQUESTS

Measures throughput for MongoDB process, as collected from the MongoDB serverStatus command's network document.
  • OPCOUNTER_CMD

  • OPCOUNTER_QUERY

  • OPCOUNTER_UPDATE

  • OPCOUNTER_DELETE

  • OPCOUNTER_GETMORE

  • OPCOUNTER_INSERT

  • SERVERLESS_OPCOUNTER_CMD

  • SERVERLESS_OPCOUNTER_QUERY

  • SERVERLESS_OPCOUNTER_UPDATE

  • SERVERLESS_OPCOUNTER_DELETE

  • SERVERLESS_OPCOUNTER_GETMORE

  • SERVERLESS_OPCOUNTER_INSERT

Measures the rate of database operations on a MongoDB process since the process last started, as collected from the MongoDB serverStatus command's opcounters document.
  • OPCOUNTER_REPL_CMD

  • OPCOUNTER_REPL_UPDATE

  • OPCOUNTER_REPL_DELETE

  • OPCOUNTER_REPL_INSERT

Measures the rate of database operations on MongoDB secondaries, as collected from the MongoDB serverStatus command's opcountersRepl document.
  • OPERATIONS_SCAN_AND_ORDER

For a selected time period, the average rate per second for operations that perform a sort but cannot perform the sort using an index.
  • AVG_READ_EXECUTION_TIME

  • AVG_WRITE_EXECUTION_TIME

  • AVG_COMMAND_EXECUTION_TIME

  • SERVERLESS_AVG_READ_EXECUTION_TIME

  • SERVERLESS_AVG_WRITE_EXECUTION_TIME

  • SERVERLESS_AVG_COMMAND_EXECUTION_TIME

The execution time in milliseconds per read, write, or command operation over the selected time period.
  • OPLOG_MASTER_TIME

  • OPLOG_MASTER_TIME_ESTIMATED_TTL

  • OPLOG_SLAVE_LAG_MASTER_TIME

  • OPLOG_MASTER_LAG_TIME_DIFF

  • OPLOG_RATE_GB_PER_HOUR

Measurements that apply to the MongoDB process's oplog.
  • QUERY_EXECUTOR_SCANNED

Average rate per second to scan index items during queries and query-plan evaluations. This rate is driven by the same value as totalKeysExamined in the output of explain. This measurement is found on the host's Query Executor chart, accessed when viewing metrics.
  • QUERY_EXECUTOR_SCANNED_OBJECTS

Average rate per second to scan documents during queries and query-plan evaluations. Atlas derives the rate using the explain output's totalDocsExamined value. This measurement is found on the host's Query Executor chart, accessed when viewing metrics.
  • QUERY_TARGETING_SCANNED_PER_RETURNED

Ratio of the number of index items scanned to the number of documents returned. This measurement is found on the host's Query Targeting chart, accessed when viewing metrics.

The change streams cursors that the Atlas Search process (mongot) uses to keep Atlas Search indexes updated can contribute to the query targeting ratio and trigger query targeting alerts if the ratio is high.

  • QUERY_TARGETING_SCANNED_OBJECTS_PER_RETURNED

Ratio of the number of documents scanned to the number of documents returned. This measurement is found on the host's Query Targeting chart, accessed when viewing metrics.

The change streams cursors that the Atlas Search process (mongot) uses to keep Atlas Search indexes updated can contribute to the query targeting ratio and trigger query targeting alerts if the ratio is high.

  • SEARCH_INDEX_SIZE

Total size of all indexes on disk in bytes.
  • SEARCH_NUMBER_OF_FIELDS_IN_INDEX

Total number of unique fields present in the Atlas Search index.
  • SEARCH_REPLICATION_LAG

Approximate number of milliseconds that Atlas Search is behind in replicating changes from the oplog of mongod.
  • SEARCH_OPCOUNTER_INSERT

  • SEARCH_OPCOUNTER_DELETE

  • SEARCH_OPCOUNTER_UPDATE

  • SEARCH_OPCOUNTER_GETMORE

Total number of Atlas Search operations.
  • SEARCH_NUMBER_OF_QUERIES_TOTAL

  • SEARCH_NUMBER_OF_QUERIES_ERROR

  • SEARCH_NUMBER_OF_QUERIES_SUCCESS

Total number of Atlas Search queries with each status.
  • SERVERLESS_TOTAL_READ_UNITS

Total serverless Read Processing Units (RPUs).
  • SWAP_USAGE_USED

  • SWAP_USAGE_FREE

  • MAX_SWAP_USAGE_USED

  • MAX_SWAP_USAGE_FREE

Swap space used and available, measured in bytes.
  • SYSTEM_MEMORY_USED

  • SYSTEM_MEMORY_FREE

  • SYSTEM_MEMORY_PERCENT_USED

Number of bytes of physical memory in use and available to the system.
  • MAX_SYSTEM_MEMORY_USED

  • MAX_SYSTEM_MEMORY_FREE

  • MAX_SYSTEM_MEMORY_PERCENT_USED

Maximum system memory values in bytes.
  • SYSTEM_MEMORY_AVAILABLE

  • MAX_SYSTEM_MEMORY_AVAILABLE

Estimate of the number of bytes of system memory available for running new applications, without swapping.
  • SYSTEM_NETWORK_IN

  • SYSTEM_NETWORK_OUT

Average rate of physical bytes received and transmitted per second by the eth0 network interface.
  • MAX_SYSTEM_NETWORK_IN

  • MAX_SYSTEM_NETWORK_OUT

Maximum values for the average rate of physical bytes (after any wire compression) sent to or from this database server per second over the selected sample period.
  • TICKETS_AVAILABLE_READS

  • TICKETS_AVAILABLE_WRITES

Measurement of the WiredTiger storage engine wiredTiger.cache and queues.execution documents as collected from the MongoDB serverStatus command.
  • NORMALIZED_SYSTEM_CPU_USER

  • NORMALIZED_SYSTEM_CPU_STEAL

CPU usage of processes on the host server, scaled to a range of 0-100% by dividing by the number of CPU cores.
  • MAX_NORMALIZED_SYSTEM_CPU_USER

  • MAX_NORMALIZED_SYSTEM_CPU_STEAL

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.

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Event Types