This topic tells you about the metrics that are emitted by all containers managed by VMware Tanzu Application Service for VMs (TAS for VMs) and its scheduling system, Diego.

App metrics include the container metrics, and any custom app metrics that developers create.

Diego Container metrics

Diego containers emit resource usage metrics for the app instance. Diego averages and emits each metric every 15 seconds.

The following table describes all Diego container metrics:

Metric Description Unit

CpuPercentage CPU time used by AI as a percentage of a single CPU core.

This is usually no greater than 100% * the number of vCPUs on the host Diego cell, but it may be more due to discrepancies in measurement timing. float64

AbsoluteCPUEntitlement CPU time that the AI was entitled to use.

At minimum, the CPU time that a Diego cell provides an AI is min(app memory, 8 GB) * (Diego cell vCPUs/Diego cell memory) * 100%.

The platform operator can provide the Diego cell vCPUs/memory ratio to developers.
If a Diego cell is not at capacity or if other workloads on it are idle, the cell can provide more than the minimum CPU. uint64

AbsoluteCPUUsage CPU time used by AI.

AbsoluteCPUUsage / AbsoluteCPUEntitlement calculates a 0-100% range of AI usage per entitlement. uint64

MemoryBytes RAM memory used by AI, in MB. uint64

MemoryBytesQuota RAM memory available, in GB. uint64

DiskBytes Disk space used by AI, in MB. uint64

DiskBytesQuota Disk space available, in GB. uint64

ContainerAge Age of container, in nanoseconds. uint64

Metric	Description	Unit
`CpuPercentage`	CPU time used by AI as a percentage of a single CPU core. This is usually no greater than `100% * the number of vCPUs on the host Diego cell`, but it may be more due to discrepancies in measurement timing.	`float64`
`AbsoluteCPUEntitlement`	CPU time that the AI was entitled to use. At minimum, the CPU time that a Diego cell provides an AI is `min(app memory, 8 GB) * (Diego cell vCPUs/Diego cell memory) * 100%`. The platform operator can provide the Diego cell `vCPUs/memory` ratio to developers. If a Diego cell is not at capacity or if other workloads on it are idle, the cell can provide more than the minimum CPU.	`uint64`
`AbsoluteCPUUsage`	CPU time used by AI. `AbsoluteCPUUsage / AbsoluteCPUEntitlement` calculates a 0-100% range of AI usage per entitlement.	`uint64`
`MemoryBytes`	RAM memory used by AI, in MB.	`uint64`
`MemoryBytesQuota`	RAM memory available, in GB.	`uint64`
`DiskBytes`	Disk space used by AI, in MB.	`uint64`
`DiskBytesQuota`	Disk space available, in GB.	`uint64`
`ContainerAge`	Age of container, in nanoseconds.	`uint64`

Loggregator v1: Most of the container metrics are emitted in a ContainerMetric envelope. The AbsoluteCPUEntitlement, AbsoluteCPUUsage, and ContainerAge container metrics are emitted as separate ValueMetric envelopes.

Loggregator v2: All container metrics are emitted in gauge envelopes. The AbsoluteCPUEntitlement, AbsoluteCPUUsage, and ContainerAge container metrics are emitted in a separate envelope to the other container metrics.

Retrieve Container Metrics from the cf CLI

You can use Cloud Foundry command-line interface (cf CLI) commands to return container metrics.

Retrieving Container metrics from the cf CLI

You can retrieve container metrics using the Cloud Foundry Command Line Interface (cf CLI).

To retrieve CPU, memory, and disk metrics for all instances of an app, see Retrieve CPU, Memory, and Disk Metrics below.

To retrieve CPU entitlement metrics for all instances of an app, see Retrieve CPU Entitlement Metrics below.

To determine when an app has exceeded its CPU entitlement, see Monitor Apps That Exceed Their CPU Entitlement below.

Retrieving CPU, Memory, and Disk metrics

To retrieve CPU, memory, and disk metrics for all instances of an app:

Run the command cf app APP-NAME.

The command output lists Diego container metric values as follows:

Label in Output	Metrics listed, as described in Diego Container Metrics, above
`cpu`	`CpuPercentage`
`memory`	`MemoryBytes` of `MemoryBytesQuota`
`disk`	`DiskBytes` of `DiskBytesQuota`

For example:

Retrieving CPU Entitlement metrics

name: dora-example requested state: started routes: dora-example.bosh-lite.com last uploaded: Fri 05 Apr 10:41:21 PDT 2019 stack: cflinuxfs3 buildpacks: ruby

type: web instances: 1/1 memory usage: 256M state since cpu memory disk details

0 running 2019-04-05T17:41:31Z 0.4% 39.5M of 256M 89.9M of 1G

Retrieve CPU Entitlement Metrics (Experimental)

To see app instance AbsoluteCPUEntitlement metrics from the command line:

Install the CPU Entitlement Plugin from cpu-entitlement-plugin in GitHub.

Determining when Apps exceed their CPU Entitlement

You can use the Cloud Foundry CPU Overentitlement Plug-in to determine when an app has exceeded its CPU entitlement and might need to be scaled up.

$ cf cpu-entitlement dora-example
Note: This feature is experimental.
Showing CPU usage against entitlement for app dora-example in org example-org / space example-org-staging as dora@example.com ...

     avg usage   curr usage
#0   1.62%       1.66%
#1   2.93%       3.09%
#2   2.51%       2.62%

Important: To avoid security exposure, verify that you migrate your apps and custom buildpacks to use the cflinuxfs4 stack based on Ubuntu 22.04 LTS (Jammy Jellyfish). The cflinuxfs3 stack is based on Ubuntu 18.04 (Bionic Beaver), which reaches end of standard support in April 2023.