TD_get_COD_limits Usage Notes - Teradata VantageCloud Lake

Lake - Monitor Resources and Performance

Deployment

VantageCloud

Edition

Lake

Product

Teradata VantageCloud Lake

Release Number

Published

February 2025

ft:locale

en-US

ft:lastEdition

2025-11-21

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wyu1683671641248.ditamap

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pny1626732985837.ditaval

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wyu1683671641248

There are two COD modes:

Mode	Description
PM COD	Platform Metering Capacity on Demand (PM COD) sets resource limits on all activities on the node. PM CPU COD uses hardware throttling at the node level. PM I/O COD throttling is done at the disk device level. Both PM I/O COD and WM I/O COD throttling are identical.
WM COD	Workload Management Capacity on Demand (WM COD) allows resource limitations to be applied to CPU and I/O for all database activity on the node. WM CPU COD uses software throttling at the node level. WM I/O COD throttling is done at the disk device level. Both PM I/O COD and WM I/O COD throttling are identical. WM COD Max is the maximum WM COD setting in WM COD mode. If there is a TDWM ruleset that exceeds WM COD Max, a message is logged and WM COD is overridden and set to WM COD Max.

Mode

Description

PM COD

Platform Metering Capacity on Demand (PM COD) sets resource limits on all activities on the node.

PM CPU COD uses hardware throttling at the node level. PM I/O COD throttling is done at the disk device level.

Both PM I/O COD and WM I/O COD throttling are identical.

WM COD

Workload Management Capacity on Demand (WM COD) allows resource limitations to be applied to CPU and I/O for all database activity on the node.

WM CPU COD uses software throttling at the node level. WM I/O COD throttling is done at the disk device level.

Both PM I/O COD and WM I/O COD throttling are identical.

WM COD Max is the maximum WM COD setting in WM COD mode. If there is a TDWM ruleset that exceeds WM COD Max, a message is logged and WM COD is overridden and set to WM COD Max.

WM COD mode is enabled on new installations. On upgrades, PM COD mode is enabled. The system can be switched to WM COD mode, which disables PM COD.

There are two types of PM COD packages:

Package teradata-pme-config-xxx, where xxx is the COD level (for example, 62.5, 75, 87.5, and so on). This package specifies the CPU and I/O limits.
Package teradata-pme-config-cpu-xxx, where xxx is the COD level (for example, 62.5, 75, 87.5, and so on). This package specifies only CPU limits.
The CPU and I/O limits are the maximum values specified by the PM COD packages that cannot be exceeded.

The function return values vary according to the mode and the PM COD packages installed.

PM COD mode returns 100% for the CPULimit and IOLimit.
WM COD mode returns 100% for the CPULimit and IOLimit, if there are no teradata-pme-config packages installed.
WM COD mode returns less than 100% for CPULimit and IOLimit, depending on the teradata-pme-config-xxx package installed.
WM COD mode returns less than 100% for CPULimit, depending on the teradata-pme-config-cpu-xxx package installed.

If you activate a Teradata dynamic workload management software ruleset that has CPU and I/O values greater than the COD maximum, the Priority Scheduler replaces the CPU and I/O values specified by the installed PM COD packages with the maximum allowable values and log a message in the messages log.

The maximum CPU and I/O COD values are global and not affected by planned environments (OpEnv). If you have multiple planned environments with different WM COD values, this is honored but is limited by the COD max value.

PM COD packages such as teradata-pme-config-62.5 or teradata-pme-config-cpu-87.5 have one tenth of a percent CPU limit granularity. For example, if the CPU maximum allowable value is 62.5%, the TD_get_COD_limits function returns 63%.