Skip to main content
Sign Out

Welcome to Dell

My Account
  • Place orders quickly and easily
  • View orders and track your shipping status
  • Enjoy members-only rewards and discounts
  • Create and access a list of your products
  • Manage your Dell EMC sites, products, and product-level contacts using Company Administration.
Sign In Create an Account Dell Financial Services Premier Sign In Partner Program Sign In
Contact Us

Your Dell.com Carts

PowerProtect Data Manager 19.14 File System User Guide

PDF

Host CPU throttling

A user with an administrator or backup role can enable the host CPU throttling feature to reduce the amount of CPU utilization by backups on the application agent host. The host CPU throttling can slow down the running backup jobs on the host and prevent any new backup jobs from starting. This feature is useful when backups on the host use a significant amount of CPU that adversely affects the existing production operations.

The user can enable the CPU throttling in the PowerProtect Data Manager UI and specify a host CPU utilization threshold or limit. When CPU utilization on the host exceeds the limit, the running backups are slowed down and new backups are queued. As a result, other processes on the same host can increase their CPU utilization and improve their response to critical tasks.

The host CPU throttling feature is supported for centralized and self-service backups with version 19.14 and later of the File System agent, Microsoft SQL Server agent, and Oracle RMAN agent. By default, CPU throttling is not enabled on an application agent host.

NOTE:

Use CPU throttling with care, on only specific hosts and in specific situations, as it can slow down the backup jobs by up to 20 times. The slowdown can cause backup jobs to run longer than the execution time window and possibly affect the compliance associated with the policies on the host.

The host CPU throttling feature is supported for Oracle Incremental Merge new backups. The feature is not supported for Oracle Incremental Merge existing in-progress centralized backups, self-service backups, or stand-alone application agents. You can enable CPU throttling for self-service Oracle RMAN agent backups through the following type of setting in the RMAN script. The backups are then slowed down: 

ALLOCATE CHANNEL C1 TYPE SBT TRACE 5 PARMS
'SBT_LIBRARY=/home/oracle/opt/dpsapps/rmanagent/lib/libddobk.so,
SBT_PARMS=(RMAN_AGENT_HOME=/home/oracle/opt/dpsapps/rmanagent/,
STORAGE_UNIT=/PLC-RAC-DG-blrv136g138-e8e4e, BACKUP_HOST=10.125.208.242,
ORACLE_HOME=/u02/software, SCHEDULED_BACKUP=TRUE, CPU_THROTTLE=90)';

For example, a user with an administrator or backup role enables the host CPU throttling and specifies the CPU utilization limit of 90% on the application agent host. The effect on the backup jobs is as follows:

  • When the host CPU utilization exceeds 90%:
    • Existing backup jobs are slowed down.
    • New backup jobs are queued on the host.
  • When the host CPU utilization is reduced to 90% or less:
    • The slowed backup jobs resume their normal speed.
    • The queued backup jobs are started.
NOTE:

It is recommended that you keep the host CPU utilization limit above 85%. Setting a limit of 85% or less can significantly slow down the backup operations. If all backup jobs become queued, then disable the CPU throttling or change the CPU utilization limit as it was likely set too low.

Running backup jobs are not affected by a change to the host CPU utilization limit. A running backup continues to use the limit value from the time that the backup job started. Backup jobs can be canceled when throttled or queued.

If the host CPU usage is consistently high without running backups, the CPU throttling feature will not be effective and backups will likely never start after you set the CPU utlilization limit. In this case, reduce the load on the host first and then use the host CPU throttling.

If the host includes pre-19.14 application agents or agents other than those for File System, Microsoft SQL Server, or Oracle RMAN, host CPU throttling is enabled, and the CPU utilization limit is exceeded:

  • New backup jobs are queued on the host.
  • Running backup jobs are not throttled.

A user can change the CPU utilization limit setting on a host as long as the host has a supported application agent. When CPU throttling is enabled on the host and then all the supported application agents are removed, the only available option for the user is to disable the CPU throttling.

Enable the host CPU throttling

To set the CPU throttling at the host level, perform the following steps as a user with an administrator or backup role.

  1. From the left navigation pane in the PowerProtect Data Manager UI, select Infrastructure > Application Agents.

    Starting with version 19.14, the lower table in the Application Agents window has two new columns that are related to host CPU throttling:

    • The Throttling Status column displays the status of backup throttling on the application agent host:
      • No Throttling—CPU throttling is not set for backups on the host.
      • Throttling—CPU throttling is set for backups on the host.
      • Unsupported—CPU throttling is unsupported because the host has only pre-19.14 application agents or application agents other than the File System agent, Microsoft SQL Server agent, or Oracle RMAN agent.

    • The CPU Throttling column displays the CPU utilization limit setting for backup throttling on the application agent host. The displayed setting is either a double dash when throttling is not set or the CPU utilization limit as a percentage between 1 to 99, inclusive.

      By default, the CPU Throttling column is hidden. To display the column, click the icon on the lower left and then select CPU Throttling from the Show/Hide Columns list.

    View application agent details provides more information about the Application Agents window.

  2. To enable the backup CPU throttling for the host and set the CPU utilization limit:

    1. In the lower table in the Application Agents window, select the application agent host.
    2. Select More Actions > Backup Throttling.

    3. In the Set Backup Throttling dialog box, specify the following fields and click Save. A system job is then created for the host CPU throttling configuration. When the CPU throttling limit is changed, an audit is also created:

      • Backup Throttling—Set the value to Enabled.

      • CPU Utilization Limit—Set the value to an integer between 1 and 99, inclusive. For example, set the value to 90 for a 90% limit. It is recommended that you keep the CPU utilization limit above 85%.

        The specified CPU utilization limit appears as a percent value in the CPU Throttling column in the table in the Application Agents window.

When backup throttling occurs, a message appears in the step log that is available through the protection job "details" view. The message states that the backup speed has slowed due to application agent throttling restrictions. When a backup job is queued during CPU throttling, the following message appears in the step log: 

Queued due to host backup throttling

On the Details tab in the protection job window, the value Yes appears after the Throttled field label when throttling has occurred at some point during the backup job.

Rate this content

Accurate
Useful
Easy to understand
Was this article helpful?
0/3000 characters
  Please provide ratings (1-5 stars).
  Please provide ratings (1-5 stars).
  Please provide ratings (1-5 stars).
  Please select whether the article was helpful or not.
  Comments cannot contain these special characters: <>()\