Skip to main content

We've Moved!

Product Documentation has moved to docs.hitachivantara.com
Hitachi Vantara Knowledge

Managing background tasks

The management of background tasks running on Content Software for File clusters is described.

The Content Software for File system has some internal/external asynchronous operations and maintenance tasks, such as migrating an object store and downloading/uploading snapshots. These tasks are performed in the background and should not interfere nor starve the Content Software for File system from serving IOs with high performance.‌

The Content Software for File system limits the CPU resources these tasks consume to 5% per host CPU.

NoteWhen the CPU is idle, background tasks can use more than the configured resources, but they are immediately freed if needed for serving IOs.
NoteThe configured limit affects both external tasks (that are visible using the GUI/CLI) and internal low-priority asynchronous operations.‌

Viewing background tasks using the CLI

It is possible to view currently-running background tasks, including their status and progress.

Commandweka cluster tasks

This command is used for viewing all background tasks. For each task, a range of data can be displayed, as shown in the following example:

# weka cluster tasks
Type       | State   | Progress | Description
-----------+---------+----------+--------------------------------------
OBS_DETACH | RUNNING | 94 | Detaching Object Storage `obs_1` from

Limiting background tasks using the CLI

It is possible to limit the resources being used by background tasks.

Commandweka cluster tasks limits

This command is used to view the currently-defined limits.

Commandweka cluster tasks limits set <cpu-limit limit>

This command is used to update the CPU limit.

Pause/Resume/Abort a background task

It is possible to pause and later resume a background task, as well as completely abort it. This is useful in case there are other tasks/activities that are of higher priority.

Command:
weka cluster task pause / resume / abort <task-id>

This command is used to pause/resume/abort the running of a specific task.

NoteUp to 16 background tasks can run in parallel. A paused (or aborting) task still consumes one of these spots.