macOS-15 routing to x86_64 after macOS-15-arm64 label was removed?

[woodrufs]

Description

The macOS-15-arm64 YAML label, which had been working successfully for Azure Pipelines
builds, stopped routing as of today (2026-03-27) with no changes on our end. Switching
to the macOS-15 label (which the readme appears to indicate is arm64) results in
successful agent assignment, but build times have doubled — reverting to durations
consistent with x86_64 execution.

Questions

1. Was macOS-15-arm64 an officially supported Azure Pipelines label? If so, was
   it intentionally removed or is this a regression?
2. Does the macOS-15 label currently route to arm64 or x86_64 hardware?
3. If macOS-15 is x86_64, what is the correct label to request an arm64 runner
   for Azure Pipelines?

Environment

• Pipeline: Azure Pipelines (Microsoft-hosted)
• Agent: sjc20-cw753-d249a61e-0d5c-45da-bf62-b50a3f680b3e-F24553D04FD2
• Agent version: 4.270.0
• Image: macos-15 (version 20260324.0317.1)
• OS: macOS 15.7.5 (24G617)
• Azure Region: westus
• Runner Image Provisioner: Hosted Compute Agent v20260213.493

Additional Context

The runner image readme linked from the agent log
(macos-15/20260324.0317) only lists x64 paths in environment variables
(e.g. JAVA_HOME_*_X64, chromedriver-mac-x64), which raises the question of
whether macOS-15 is actually serving arm64 hardware at all.

Note: I do not have uname -m output from the affected runs to confirm architecture
definitively — happy to provide this if it would help investigation.

Platforms affected

• Azure DevOps
• GitHub Actions - Standard Runners
• GitHub Actions - Larger Runners

Runner images affected

• Ubuntu 22.04
• Ubuntu 24.04
• Ubuntu Slim
• macOS 14
• macOS 14 Arm64
• macOS 15
• macOS 15 Arm64
• macOS 26
• macOS 26 Arm64
• Windows Server 2022
• Windows Server 2025
• Windows Server 2025 with Visual Studio 2026

Image version and build link

Image: macos-15
Version: 20260324.0317.1

Note: previous builds with arm64 said Image was macos-15-arm64

Is it regression?

Yes, builds from yesterday worked using: Image: macos-15-arm64 Version: 20260325.0234.1

Expected behavior

macOS-15-arm64 routes successfully to an arm64 runner, or macOS-15 is confirmed
as arm64 and builds run at arm64 speeds.

Actual behavior

The pipeline errors immediately with:

[error]No image label found to route agent pool Azure Pipelines.

Switching the label to macOS-15 resolves the routing error, but build times
doubled from ~30 minutes (previously observed on arm64) to ~60 minutes (consistent
with our prior experience on x86_64).

Repro steps

1. Use vmImage: macOS-15-arm64 in an Azure Pipelines YAML file
2. Queue a build

[v-GeorgyPuzakov]

Hi @woodrufs, We will have a look and get back to you.

[woodrufs]

Hi @v-GeorgyPuzakov - thank you for reaching out. This morning, I did notice that Microsoft updated their docs with this note:

My org is using the public pool to build our iOS app, so I assume that is why I have been impacted. I was referencing the docs in the readme of this repository, which feels like they might be out of sync. Loved the arm64 machine since it cut our build time in half 😃

[agarshubh]

Hi @woodrufs the preview of macOS-15 ARM64 images have been paused. Please look out for announcements on this page around early June for the availability of these images

[Jon889]

Hi @woodrufs the preview of macOS-15 ARM64 images have been paused. Please look out for announcements on this page around early June for the availability of these images

Does the documentation need to be updated to remove the sentence "Any Azure DevOps organization currently using it can continue to do so."?