storage

const (
	// Default disk path
	DefaultDiskPath = "/var/cache"

	// Default TTL (seconds) when no key-level TTL is set
	DefaultTTL = 0

	// Default inline threshold (bytes) for small objects that are inlined in RocksDB
	DefaultInlineThreshold = 64 * 1024 // 64KB

	// Default compact threshold (bytes) for objects that are compacted to segments
	DefaultCompactThreshold = 64 * 1024 * 1024 // 64MB

	// Default segment size (bytes)
	DefaultSegmentSize = 256 * 1024 * 1024 // 256MB

	// Default file descriptor cache size (entries)
	DefaultFdCacheSize = 10000

	// Default max disk usage (bytes)
	DefaultMaxDiskUsage = 0

	// Default compaction threads
	DefaultCompactionThreads = 1 // Default to single thread for backwards compatibility

	// DefaultCompactionBytesPerSecond reserves most of a typical capped volume
	// for serving reads while background compaction drains its backlog. It is
	// the SERVER FLAG default only (see server/config.go): the storage layer
	// treats a non-positive CompactionBytesPerSecond as unthrottled, matching
	// the 0-disables convention of MaxDiskUsage, so directly constructed and
	// embedded storage keeps its historical unthrottled behavior unless a
	// budget is set explicitly.
	DefaultCompactionBytesPerSecond int64 = 16 * 1024 * 1024 // 16 MiB/s

	// Default TTL cleanup interval
	DefaultTTLCleanupInterval = 1 * time.Minute

	// Default access update buffer size, batch interval and delay
	DefaultAccessUpdateBufferSize = 100000
	DefaultAccessUpdateInterval   = 1 * time.Second
	DefaultAccessUpdateDelay      = 5 * time.Minute

	// Default queue config
	DefaultDeleteBatchSize = 1000 // Number of deletions to process per batch

	// Default segment recompaction settings
	DefaultRecompactionDisabled          = false
	DefaultFragmentationThreshold        = 0.5             // Recompact when dead space exceeds 50%
	DefaultMinSegmentAgeForRecompaction  = 2 * time.Hour   // Don't recompact segments younger than 2 hours (ensures they're cold)
	DefaultMinSegmentsBeforeRecompaction = 2               // Minimum number of segments required for recompaction
	DefaultRecompactionInterval          = 1 * time.Minute // Interval between segment recompaction runs

	// Default delete queue settings
	DeleteProcessInterval = time.Second      // Interval between batch processing
	DeletePruneAge        = 24 * time.Hour   // Age after which entries are pruned
	DeleteRetryDelay      = 30 * time.Second // Backoff before retrying a failed deletion (bounds retry churn for stuck files)

	// Default number of parallel workers for startup file recovery
	DefaultRecoveryWorkers = files.MaxWorkers

	// Default RocksDB configuration
	DefaultMetadataCacheSize      = metadata.DefaultRocksDBBlockCacheSize
	DefaultMetadataBackgroundJobs = metadata.DefaultRocksDBMaxBackgroundJobs

	// Eviction policies for StorageConfig.EvictionPolicy (only relevant when
	// MaxDiskUsage > 0). Each policy maintains its own eviction index:
	//
	//   lru  - evict least-recently-accessed first, using the time-bucketed
	//          access index; a read re-buckets the entry, protecting recently
	//          -read data.
	//   fifo - evict oldest-written first, using the dedicated !fifo/ index;
	//          entries are written once at Put and never touched by reads, so a
	//          read of old data does not protect it from eviction.
	EvictionPolicyLRU  = "lru"
	EvictionPolicyFIFO = "fifo"

	// DefaultEvictionPolicy preserves the historical behavior (LRU).
	DefaultEvictionPolicy = EvictionPolicyLRU
)

const (
	// BucketDuration defines the time window for each bucket (1 hour)
	BucketDuration = time.Hour
)

const MaxListValueSize int64 = 1 << 20 // 1 MiB