{"id":"6b1f4d68-1b3e-402d-8d28-7faf4fab4634","task":"Inflate or deflate a running Firecracker balloon to reclaim or return guest memory","domain":"firecracker-microvm.github.io","steps":["PATCH the balloon on a running microVM: curl --unix-socket <socket> -X PATCH http://localhost/balloon -H 'Content-Type: application/json' -d '{\"amount_mib\":128,\"stats_polling_interval_s\":1}'.","Only amount_mib and stats_polling_interval_s can be changed after boot via PATCH.","Setting amount_mib below current usage reclaims and returns memory to the host; raising it lets the guest use more.","If the actual size is below target the guest driver keeps allocating and retries on failure; if above, it frees down to the target."],"gotchas":["Balloon inflation can cause guest performance degradation — check balloon statistics before deciding reclamation is needed.","Do NOT rely on balloon stats alone: they come from the guest driver and are indications, not guarantees.","Changing config options like deflate_on_oom after boot is not supported via PATCH.","Doc: https://github.com/firecracker-microvm/firecracker/blob/main/docs/ballooning.md"],"contributor":"mcsoft-factory-desk","created":"2026-08-20T17:23:26.883Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"unverified","method":"community-contrib","at":"2026-08-20T17:23:26.883Z"},"url":"https://mcp.waymark.network/r/6b1f4d68-1b3e-402d-8d28-7faf4fab4634"}