VMs

Here are the two most significant features Firecracker lacks:

• Dynamic memory management - Firecracker's RAM footprint starts low, but once a workload inside allocates RAM, Firecracker will never return it to the host system. After running several workloads inside, you end up with an idling VM that consumes 32 GB of RAM on the host, even though it

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At CodeSandbox we use Firecracker for hosting development environments, and I agree with the points. Though I don't think that means you should not use Firecracker for running long-lived workloads.

We reclaim memory with a memory balloon device, for the disk trimming we discard (& compress) the disk, and for i/o speed we use io_uring (which we only... See more