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Release 2.15.00

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Note: It is currently a best practice to use a Services Machine with a minimum of 32GB of RAM. Starting in 2019 it will become required. See docs for our recommendation(s).

What’s New in Release 2.15

This release contains an upgrade to MongoDB, service migrations for contexts and is a required upgrade. The following updates and fixes are also of note:

MongoDB Upgrade The MongoDB version running on Services VM will be automatically updated from 3.2 to 3.6 for you. If you have externalized MongoDB and wish to upgrade to 3.6, please contact your CSM

Bug Fix Restrict interaction of Workflows ‘Rerun’ dropdown to users who are part of GitHub organization for open-source projects.

Bug Fix Known issue for broken UI due to workflows with “.” in the name

Bug Fix Known performance issue with freezed browsers for organizations with many branches.

Bug Fix Known issue for Vault auth tokens not being automatically renewed. If you have externalized Vault, please contact your CSM before you upgrade to 2.15.0

New Feature: Splitting test files via Workflows. If your project has a large number of tests, you can use circleci tests split feature to reduce your job run time. For more information on how to setup tests split, please follow this document.

New Feature: Workflows UI will now show actors who have taken the following actions:

  • Rerun workflows
  • Approved jobs
  • Canceled jobs

New Feature We are excited to announce more Metrics! Nomad job metrics can be enabled and will be emitted by the Nomad Server. Please see Nomad Metrics documentation for instructions on how to configure Nomad Clients. The following five types of metrics are reported:

  • circle.nomad.server_agent.poll_failure: Returns 1 if the last poll of the Nomad agent failed, otherwise it returns 0.
  • Returns the total number of pending jobs across the cluster.
  • Returns the total number of running jobs across the cluster.
  • Returns the total number of complete jobs across the cluster.
  • Returns the total number of dead jobs across the cluster.

New Feature Host (Services VM) and docker metrics can now be forwarded via Telegraf , a plugin-driven server agent for collecting & reporting metrics, to DataDog or a custom location. To enable and/or configure please go to For more information please see the Monitoring documentation.

Performance Improvement Reduced the load time for all workflows pages.

Performance Improvement CircleCI has upgraded the mechanism that returns gettimeofday calls. As a result, heavy users of syscall will see an aggregate improvement in performance. Most noticeably this will improve the run time of projects with heavy usage of debugging/profiling tools and Xdebug with PHP.

Updated JVM_HEAP_SIZE is configurable for frontend, output-processor, and test-result containers. Please see JVM Heap Size Configuration documentation.

Updated For customers running the Static installation, Ubuntu 16.04 (Xenial) has been added as a supported OS. For additional details please see the docs.

Known Issue(s)

When a saved context is removed during the build graph phase it can cause a silent failure during job execution.
When using the none storage driver, the cache will not be saved. This means that you currently cannot use caching in CircleCI when you are using the none storage driver.