CapabilitiesSizes and regions
Resize while running
Change CPU or memory without stopping the machine or losing what is running.
Who offers it
Part of Sizes, regions and hardware, which explains why it matters.
Fully: Tensorlake. With a catch: Agent 37, Blaxel, Daytona, InstaBox, Morph and Runtime. Not at all: Boat, boxd, Cloudflare Sandbox, E2B, Lizard, Modal, Sandboxer, Sprites and Vercel Sandbox.
Memory can only shrink back to about what the running programs are using.
docs-confirmed “A sandbox can change its CPU, memory, and root disk allocation while it runs.” Source
The catch: You can change the size without stopping the machine, but it may move to another host and everything running in memory is lost.
docs-confirmed “start and resize answer 202 instead of 200 when they moved the instance to another host” Source
The catch: You can change the memory, but the sandbox resets, so anything running is lost.
docs-confirmed “Updates a sandbox's configuration. Note that certain changes (like image or memory) may reset the sandbox state.” Source
The catch: You can add cores and memory while it runs, but you cannot shrink them, and the feature has to be switched on by support first.
docs-confirmed “On a running sandbox, you can increase CPU and memory without interruption.” Source
The catch: Cores and memory change only while the machine is stopped, and take effect at its next start; the free plan cannot resize at all.
docs-confirmed “A paid machine moves to another size of its plan while stopped” Source
The catch: Disk space can grow while the machine runs, but changing cores or memory means restarting it.
docs-confirmed “CPU and memory changes still require reboot.” Source
The catch: You can change the memory only while the machine is paused, not while it is working.
docs-confirmed “resize this one while it is paused” Source
Note: Changing the size means stopping the machine and starting it again.
docs-confirmed “To change the size, stop the sandbox, then resume it with --type.” Source
Note: A size change reboots the machine, so running programs are lost.
docs-confirmed “A running machine reboots to apply it, so its disk persists and running processes are lost.” Source
Note: The size is fixed when the sandbox is deployed; changing it means deploying again.
Inferred from the instance type being set at deploy time.
inferred “Maximum vCPU” Source
Note: The machine keeps the size it was created with; there is no resize.
Inferred: no resize call appears in the docs or API reference.
inferred “Max vCPUs” Source
Note: The size is chosen when the sandbox is created and cannot be changed.
Inferred: the size list is closed and no resize is documented.
inferred “Sandbox sizes run from Small (2 vCPU / 4 GB) to Large (8 vCPU / 16 GB)” Source
Note: Resources are fixed when the sandbox is created; changing them means starting a new one.
Inferred: no resize method is documented.
inferred “Sandboxes have the same disk limits as other Modal containers” Source
Note: There is no way to change a running machine's size; you create a new one and copy your files across.
docs-confirmed “Moving to a smaller size isn't supported yet. To go smaller, create a new sandbox of that size and copy your files across” Source
Note: The shape is fixed, so there is nothing to resize.
docs-confirmed “The vCPU count and the storage ceiling are fixed” Source
Note: The size is set when the sandbox is created and cannot be changed during its life.
Inferred: no resize in the SDK reference.
inferred “Each vCPU includes 2 GB of memory.” Source
Related
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