GitLab CI job log size limit exceeded

What this failure means

The GitLab CI job produced more output than the runner’s configured log size limit. GitLab truncates the log and marks the job as failed.

Symptoms

Faultline looks for one or more of these log fragments:

Job's log exceeded limit
job log size exceeded
Archiving trace
log limit exceeded
truncated log
CI_JOB_LOG_LIMIT
trace size
job trace exceeded

Diagnosis

GitLab enforces a maximum log size per job (default 100 MB for self-managed instances; GitLab.com uses a lower limit). When the job output reaches that ceiling, the runner stops archiving the trace, truncates the log, and fails the job.

Common causes:

• A verbose build tool printing every dependency download (Maven, Gradle, npm with --verbose).
• A test suite printing full diff output or stack traces for a large number of failures.
• A debug flag (set -x, CI_DEBUG_TRACE=true, or --log-level debug) left enabled in production workflows.
• An infinite loop or very long-running command that continuously writes to stdout.
• Unnecessary progress bars or animated output captured as static log lines.

Fix steps

1. Identify which step is generating volume: look at the truncated log for the start of the last heavy section.

2. Reduce verbosity:

   • Maven: add -q (quiet) or remove -X (debug) from the mvn invocation.
   • Gradle: remove --info or --debug; add --quiet for builds that pass.
   • npm: remove --verbose; use npm ci --prefer-offline 2>&1 | grep -v "^npm http" to suppress download noise.

3. For test output, configure the test reporter to print only failures:

   # pytest: show only failures
   pytest -q --tb=short
   # Jest: suppress pass summaries
   jest --silent
   

4. Remove CI_DEBUG_TRACE: "true" or set -x from the job configuration.

5. For self-managed GitLab, raise the log size limit in the runner configuration (max_log_size) or in the GitLab admin panel under Settings → CI/CD → Maximum job log file size.

6. Split the noisy job into smaller stages so each stage’s output fits within the limit.

Validation

• Re-run the job and confirm it completes without the log-limit message.
• wc -c on a captured log file should be well below the runner’s configured limit.

Try it locally

# Remove verbose flags from the failing job and re-run
# To measure: wc -c <captured-log-file>
# Confirm job completes without truncation message

How Faultline detects it

Use faultline explain gitlab-job-log-limit to see the full playbook.

faultline analyze build.log
faultline explain gitlab-job-log-limit

Generated from playbooks/bundled/log/ci/gitlab-job-log-limit.yaml. Do not edit directly.