hashfolder

const (
	// EVENT_FULL, EVENT_ARRIVE, EVENT_ABSORB, EVENT_VACATE, EVENT_BALANCE, and
	// EVENT_CLAIM are hash_space_pending_event.event_kind values.
	EVENT_FULL    = "full"
	EVENT_ARRIVE  = "arrive"
	EVENT_ABSORB  = "absorb"
	EVENT_VACATE  = "vacate"
	EVENT_BALANCE = "balance"
	EVENT_CLAIM   = "claim"

	// ROOM_RETURN_MIN is the capacity increase that asks a disk to take
	// bytes back after other filesystem activity frees space.
	ROOM_RETURN_MIN = 1 << 30

	// REFRESH_INTERVAL is how often a node republishes used counters and runs a
	// queued event. Map edits reload the local snapshot and notify other nodes.
	REFRESH_INTERVAL = FLUSH_INTERVAL

	CAS_RETRIES = 20

	// NOTIFY_TIMEOUT bounds each map-change notification to another node.
	NOTIFY_TIMEOUT = 5 * time.Second

	// LIST_PAGE is how many directory entries a rebalance scan reads at once.
	LIST_PAGE = 256

	// MOVE_STALE is how long a move row may sit without HashSpaceMove starting
	// it before the row is obsolete and the destination is treated as missing.
	MOVE_STALE = 48 * time.Hour
)

const (
	// SPLIT is the folder split. The first two hex characters of the CID hash
	// are the directory and the rest is the file name: abcdefg is ab/cdefg.
	SPLIT = "2,-"

	// DIR_OPEN and DIR_ACL are the space folders on each storage root.
	DIR_OPEN = "open-pieces"
	DIR_ACL  = "acl-pieces"

	// HASH_BYTES is the CID hash width used for layout ranges.
	HASH_BYTES = 32

	// FLUSH_INTERVAL is how often a loaded space rewrites its layout.
	// It matches the storage heartbeat cadence.
	FLUSH_INTERVAL = 10 * time.Second
)

const (
	// MIGRATE_BATCH is how many piece-park files are renamed before their
	// sector_location rows are dropped in one statement.
	MIGRATE_BATCH = 10_000

	// MIGRATE_WORKERS_PER_DISK is how many renames and copies run at once
	// for each disk being migrated.
	MIGRATE_WORKERS_PER_DISK = 5

	// MIGRATE_PROGRESS_INTERVAL is how often migration progress is printed.
	MIGRATE_PROGRESS_INTERVAL = 5 * time.Second

	// MIGRATE_RETRY_MIN and MIGRATE_RETRY_MAX bound the wait before a failed
	// migration pass runs again. Startup waits until a pass succeeds.
	MIGRATE_RETRY_MIN = 5 * time.Second
	MIGRATE_RETRY_MAX = 2 * time.Minute

	// MIGRATE_SKIP_SAMPLES is how many pieces of one skip reason are logged
	// with their ids. Later ones of that reason are only counted.
	MIGRATE_SKIP_SAMPLES = 32
)

const OVERLAP_CHECK_INTERVAL = 10 * time.Minute

const SNAPSHOT_RETRIES = 3