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Detailed Database Metrics - Amazon Relational Database Service

Detailed Database Metrics

Counter metrics are operating system and database performance metrics. These metrics are exposed through the Performance Insights API. To help identify and analyze performance problems, you can correlate counter metrics with DB load. You must append a statistic function to the metric to get the metric values. For example, the supported functions for os.memory.active metric are .avg, .min, .max, .sum, and .sample_count.

The counter metrics are collected one time each minute. The OS metrics collection depends on whether Enhanced Monitoring is turned on or off. If Enhanced Monitoring is turned off, the OS metrics are collected one time each minute. If Enhanced Monitoring is turned on, the OS metrics are collected for the selected time period. For more information about turning Enhanced Monitoring on or off, see Turning Enhanced Monitoring on and off.

Operating system counters

The following operating system counters, which are prefixed with os, are available through the Performance Insights API for all RDS engines except RDS for SQL Server .

You can use ListAvailableResourceMetrics API for the list of available counter metrics for your DB instance. For more information, see ListAvailableResourceMetrics in the Amazon RDS Performance Insights API Reference guide.

Counter Type Unit Metric Description
Active Memory Kilobytes os.memory.active The amount of assigned memory, in kilobytes.
Buffers Memory Kilobytes os.memory.buffers The amount of memory used for buffering I/O requests prior to writing to the storage device, in kilobytes.
Cached Memory Kilobytes os.memory.cached The amount of memory used for caching file system–based I/O, in kilobytes.
DB Cache Memory Bytes os.memory.db.cache

The amount of memory used for page cache by database process including tmpfs (shmem), in bytes.

DB Resident Set Size Memory Bytes os.memory.db.residentSetSize

The amount of memory used for anonymous and swap cache by database process not including tmpfs (shmem), in bytes.

DB Swap Memory Bytes os.memory.db.swap

The amount of memory used for swap by database process, in bytes.

Dirty Memory Kilobytes os.memory.dirty The amount of memory pages in RAM that have been modified but not written to their related data block in storage, in kilobytes.
Free Memory Kilobytes os.memory.free The amount of unassigned memory, in kilobytes.
Huge Pages Free Memory Pages os.memory.hugePagesFree The number of free huge pages. Huge pages are a feature of the Linux kernel.
Huge Pages Rsvd Memory Pages os.memory.hugePagesRsvd The number of committed huge pages.
Huge Pages Size Memory Kilobytes os.memory.hugePagesSize The size for each huge pages unit, in kilobytes.
Huge Pages Surp Memory Pages os.memory.hugePagesSurp The number of available surplus huge pages over the total.
Huge Pages Total Memory Pages os.memory.hugePagesTotal The total number of huge pages.
Inactive Memory Kilobytes os.memory.inactive The amount of least-frequently used memory pages, in kilobytes.
Mapped Memory Kilobytes os.memory.mapped The total amount of file-system contents that is memory mapped inside a process address space, in kilobytes.
Out of Memory Kill Count Memory Kills os.memory.outOfMemoryKillCount

The number of OOM kills that happened over the last collection interval.

Page Tables Memory Kilobytes os.memory.pageTables The amount of memory used by page tables, in kilobytes.
Slab Memory Kilobytes os.memory.slab The amount of reusable kernel data structures, in kilobytes.
Total Memory Kilobytes os.memory.total The total amount of memory, in kilobytes.
Writeback Memory Kilobytes os.memory.writeback The amount of dirty pages in RAM that are still being written to the backing storage, in kilobytes.
Guest Cpu Utilization Percentage os.cpuUtilization.guest The percentage of CPU in use by guest programs.
Idle Cpu Utilization Percentage os.cpuUtilization.idle The percentage of CPU that is idle.
Irq Cpu Utilization Percentage os.cpuUtilization.irq The percentage of CPU in use by software interrupts.
Nice Cpu Utilization Percentage os.cpuUtilization.nice The percentage of CPU in use by programs running at lowest priority.
Steal Cpu Utilization Percentage os.cpuUtilization.steal The percentage of CPU in use by other virtual machines.
System Cpu Utilization Percentage os.cpuUtilization.system The percentage of CPU in use by the kernel.
Total Cpu Utilization Percentage os.cpuUtilization.total The total percentage of the CPU in use. This value includes the nice value.
User Cpu Utilization Percentage os.cpuUtilization.user The percentage of CPU in use by user programs.
Wait Cpu Utilization Percentage os.cpuUtilization.wait The percentage of CPU unused while waiting for I/O access.

Read IOs PS

Disk IO Requests per second

os.diskIO.<devicename>.readIOsPS

The number of read operations per second.

Write IOs PS

Disk IO Requests per second

os.diskIO.<devicename>.writeIOsPS

The number of write operations per second.

Avg Queue Len

Disk IO Requests

os.diskIO.<devicename>.avgQueueLen

The number of requests waiting in the I/O device's queue.

Avg Req Sz

Disk IO Requests

os.diskIO.<devicename>.avgReqSz

The number of requests waiting in the I/O device's queue.

Await

Disk IO Milliseconds

os.diskIO.<devicename>.await

The number of milliseconds required to respond to requests, including queue time and service time.

Read IOs PS

Disk IO Requests

os.diskIO.<devicename>.readIOsPS

The number of read operations per second.

Read KB

Disk IO Kilobytes

os.diskIO.<devicename>.readKb

The total number of kilobytes read.

Read KB PS

Disk IO Kilobytes per second

os.diskIO.<devicename>.readKbPS

The number of kilobytes read per second.

Rrqm PS

Disk IO Requests per second

os.diskIO.<devicename>.rrqmPS

The number of merged read requests queued per second.

TPS

Disk IO Transactions per second

os.diskIO.<devicename>.tps

The number of I/O transactions per second.

Util

Disk IO Percentage

os.diskIO.<devicename>.util

The percentage of CPU time during which requests were issued.

Write KB

Disk IO Kilobytes

os.diskIO.<devicename>.writeKb

The total number of kilobytes written.

Write KB PS

Disk IO Kilobytes per second

os.diskIO.<devicename>.writeKbPS

The number of kilobytes written per second.

Wrqm PS

Disk IO Requests per second

os.diskIO.<devicename>.wrqmPS

The number of merged write requests queued per second.
Blocked Tasks Tasks os.tasks.blocked The number of tasks that are blocked.
Running Tasks Tasks os.tasks.running The number of tasks that are running.
Sleeping Tasks Tasks os.tasks.sleeping The number of tasks that are sleeping.
Stopped Tasks Tasks os.tasks.stopped The number of tasks that are stopped.
Total Tasks Tasks os.tasks.total The total number of tasks.
Zombie Tasks Tasks os.tasks.zombie The number of child tasks that are inactive with an active parent task.
One Load Average Minute Processes os.loadAverageMinute.one The number of processes requesting CPU time over the last minute.
Fifteen Load Average Minute Processes os.loadAverageMinute.fifteen The number of processes requesting CPU time over the last 15 minutes.
Five Load Average Minute Processes os.loadAverageMinute.five The number of processes requesting CPU time over the last 5 minutes.
Cached Swap Kilobytes os.swap.cached The amount of swap memory, in kilobytes, used as cache memory.
Free Swap Kilobytes os.swap.free The amount of swap memory free, in kilobytes.
In Swap Kilobytes os.swap.in The amount of memory, in kilobytes, swapped in from disk.
Out Swap Kilobytes os.swap.out The amount of memory, in kilobytes, swapped out to disk.
Total Swap Kilobytes os.swap.total

The total amount of swap memory available in kilobytes.

Max Files File Sys Files os.fileSys.maxFiles The maximum number of files that can be created for the file system across all storage volumes.
Used Files File Sys Files os.fileSys.usedFiles The number of files in the file system across all storage volumes.
Used File Percent File Sys Files os.fileSys.usedFilePercent The percentage of available files in use across all storage volumes.
Used Percent File Sys Percentage os.fileSys.usedPercent The percentage of the file-system disk space in use across all storage volumes.
Used File Sys Kilobytes os.fileSys.used The amount of disk space used by files in the file system across all storage volumes, in kilobytes.
Total File Sys Kilobytes os.fileSys.total The total disk space available for the file system across all storage volumes, in kilobytes.
Max Files