Announcing our new CI/CD runtime, with up to 8x faster builds

We recently gave you a preview of some exciting changes coming to Bitbucket Pipelines with the release of our next-generation CI/CD runtime. This new runtime will act as the foundation for a range of powerful new future capabilities like ARM and multi-arch builds in cloud, and we're excited to announce that this new runtime is available starting today.

With today's launch, you can enable significantly larger instance sizes for your CI/CD workloads – giving your teams up to 8x more CPU and memory for their builds.

Important: This post includes a deprecation notice for Pipelines’ legacy cloud runtime. If you use IP allowlisting as part of your CI/CD setup, it is important you review the "Retirement of legacy runtime and IP changes" section below.

Increase CPU and memory allocation for your builds

You can now specify two new sizes for your builds running in Bitbucket Pipelines with the new 4x and 8x build sizes.

Note: Please be aware that the new Pipelines size options are only available for builds running under a paid Bitbucket Cloud plan (Standard or Premium).

Any builds run with these new size properties will automatically be provisioned on the new runtime which gives them access to both increased CPU and memory, as well as dedicated compute resources that are assigned exclusively to your builds.

We're reworking the build size numbering scheme for Bitbucket Pipelines, starting with 4x & 8x which will be moving to a standardised sizing ratio with dedicated CPU and memory that scales directly in line with the increased build size number.

For more information on setting-up and using the larger step sizes, check out the Pipelines documentation.

For reference:

  • 4x builds will be provisioned with 8 CPU cores and 16GB of memory.
  • 8x builds will be provisioned with 16 CPU cores and 32GB of memory.

New Pipelines runtime:

Steps using the new 4x and 8x sizes will automatically be set up on the new Pipelines runtime, whilst steps running on the existing 1x and 2x sizes will continue using the legacy runtime until September.

It's important to be aware that there are some underlying changes to the Pipeline platform that, in extremely rare scenarios, may cause unexpected behaviours in your builds.

If your builds rely on specific elements of the current runtime environment (such as specific Linux kernel versions, or specific numbers of CPU cores being visible to the build container), we recommend you do detailed end-to-end testing of your builds on the new runtime, prior to making it your default execution environment.

Not sure if this applies to you? Then you shouldn’t need to worry about it.

Retirement of legacy runtime and IP changes

On September 17th, 2024, we will be retiring the legacy Pipelines runtime for builds running on 1x and 2x sizes. Those step sizes will be automatically migrated to the new Pipelines runtime, as part of this process.

To be clear, 1x and 2x sizes are not being retired, they are simply being moved to the new Pipelines runtime.

As part of this deprecation:

  • No changes are required in your Pipelines configuration.
  • If you use IP allowlisting to control access to your internal networks from Pipelines, please update to the new IP address ranges for the new runtime as listed in the Pipelines documentation prior to September 17th.

We recommend conducting some basic end-to-end testing of your 1x and 2x builds on the new 4x build size prior to September 17th, even if you do not intend to use the larger step sizes for production loads. This will give you a chance to identify any potential incompatibilities between your current CI/CD workflow and the new runtime.

For context, Atlassian has been running on this new runtime for it's internal CI/CD for an extensive period of time and has completed millions of builds with it, with no major incompatibility being experienced.