flyctl machine run and update accept --vm-max-memory
Introduced 2026-03-23 · score 0.92
HOW TO USE IT
When running a new machine or updating an existing one, pass `--vm-max-memory <memory>` to set its maximum memory in MB. The v0.4.27 source documents the flag as hidden and rejects zero or invalid sizes.
fly machine run <image> --vm-max-memory <memory> --app <app-name>fly machine update <machine-id> --vm-max-memory <memory> --app <app-name>WHY THIS HELPS
Set a machine's maximum memory while running or updating it.
REQUIREMENTS AND LIMITATIONS
- Version: v0.4.27
- --vm-max-memory <memory>: Maximum memory, in megabytes, allowed for the VM. Parsed as a size; zero is rejected. The flag is hidden and has no alias.
- <image> (required): Image or Dockerfile path argument for `machine run`.
- <machine-id> (required): Machine identifier argument for `machine update`.
- --app <app-name>: Application name; the run command source lists the app flag.
- Docs conflict: The run command source page is on master, newer than v0.4.27; it is used only for the `<image>` argument, not for the new flag behavior.
FIRST-PARTY EVIDENCE
- https://github.com/superfly/flyctl/releases/tag/v0.4.27
- https://github.com/superfly/flyctl/pull/4793
- https://github.com/superfly/flyctl/blob/v0.4.27/internal/flag/machines.go
- https://github.com/superfly/flyctl/blob/master/internal/command/machine/run.go
Check the installed version and the source before using it. Entry JSON