Disk space management in Jenkins - Step-by-Step Execution

Process Flow - Disk space management

Start Jenkins Job

↓

Check Disk Space

↓

Is Disk Space < Threshold?

No→Continue Job

Yes↓

Clean Workspace and Old Builds

↓

Re-check Disk Space

↓

Enough Space?

No→Fail Job or Alert Admin

Yes↓

Continue Job Execution

This flow shows how Jenkins checks disk space before running jobs, cleans up if needed, and decides whether to continue or stop.

Execution Sample

Jenkins

node {
  def freeSpaceStr = sh(script: "df --output=avail -B1 ${WORKSPACE} | tail -1", returnStdout: true).trim()
  def freeSpace = freeSpaceStr.toLong()
  if (freeSpace < 5000000000L) {
    cleanWs()
    freeSpaceStr = sh(script: "df --output=avail -B1 ${WORKSPACE} | tail -1", returnStdout: true).trim()
    freeSpace = freeSpaceStr.toLong()
  }
  echo "Free space: ${freeSpace}"
}

This Jenkins pipeline script checks free disk space, cleans workspace if below 5GB, then prints free space.

Process Table

Step	Action	Disk Space (bytes)	Condition	Result
1	Start job and check disk space	4000000000	4000000000 < 5000000000?	True - proceed to cleanup
2	Run cleanWs() to clean workspace	7000000000	N/A	Workspace cleaned, disk space increased
3	Print free space after cleanup	7000000000	7000000000 < 5000000000?	False - enough space, continue job
4	Job continues execution	7000000000	N/A	Job runs successfully

💡 Disk space after cleanup is sufficient, job continues normally.

Status Tracker

Variable	Start	After Step 1	After Step 2	Final
freeSpace	N/A	4000000000	7000000000	7000000000

Key Moments - 3 Insights

Why do we check disk space before cleaning the workspace?

Because if disk space is already enough (see Step 1 in execution_table), cleaning is unnecessary and saves time.

How does cleanWs() affect disk space?

cleanWs() deletes old files and builds, increasing free disk space as shown from 4GB to 7GB in Step 2.

What happens if disk space is still low after cleanup?

The job should fail or alert admin to prevent running with insufficient space, but in this example, space is enough after cleanup.

Visual Quiz - 3 Questions

Look at the execution table, what is the disk space value after running cleanWs()?

A 7000000000

B 5000000000

C 4000000000

D 3000000000

💡 Hint

Check Step 2 in the execution_table under 'Disk Space (bytes)' column.

At which step does the condition 'freeSpace < 5000000000' become false?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the 'Condition' column in execution_table for each step.

If the initial disk space was 6000000000 bytes, what would happen at Step 1?

A Cleanup would run

B Job would continue without cleanup

C Job would fail immediately

D Disk space would decrease

💡 Hint

Refer to the condition check in Step 1 of execution_table.

Concept Snapshot

Jenkins Disk Space Management:
- Check disk space before job runs
- If below threshold, run cleanWs() to free space
- Re-check space; if enough, continue job
- If still low, fail job or alert
- Helps prevent job failures due to disk full

Full Transcript

This visual execution shows how Jenkins manages disk space during job runs. First, it checks the available disk space. If the space is less than 5GB, it cleans the workspace using cleanWs() to free up space. After cleanup, it checks disk space again. If the space is sufficient, the job continues normally. If not, the job should fail or alert an administrator. This process helps avoid job failures caused by insufficient disk space.