velarixdb 0.0.17

An LSM Storage Engine focused on reduced IO amplification
Documentation 
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use crate::{
    bucket::BucketMap,
    key_range::KeyRange,
    memtable::{MemTable, SkipMapValue},
};
use chrono::{DateTime, Utc};
use crossbeam_skiplist::SkipMap;
use std::sync::Arc;
use tokio::sync::RwLock;

/// Contains type aliases to help with readability
/// Represents a key
pub type Key = Vec<u8>;

/// Represents a value
pub type Value = Vec<u8>;

/// Alias for value offset in vlog file
pub type ValOffset = usize;

/// Represents the creation time of an entity
pub type CreatedAt = DateTime<Utc>;

// Represents when an entity was last modified
pub type LastModified = DateTime<Utc>;

/// Represents a tombstone marker (true if entry is deleted)
pub type IsTombStone = bool;

/// Represents singal sent after flush
pub type FlushSignal = u8;

/// Represents the number of bytes read
pub type NoBytesRead = usize;

/// Represents entries in a SkipMap with generic key type wih order trait
pub type SkipMapEntries<K> = Arc<SkipMap<K, SkipMapValue<ValOffset>>>;

/// Represents a receiver for flush signal
pub type FlushReceiver = async_broadcast::Receiver<FlushSignal>;

/// Thread-safe BucketMap
pub type BucketMapHandle = Arc<RwLock<BucketMap>>;

/// Thread-safe KeyRange type
pub type KeyRangeHandle = Arc<KeyRange>;

/// Represents read-only MemTables
pub type ImmutableMemTables<K> = Arc<SkipMap<K, Arc<MemTable<K>>>>;

/// Represents read-only memtables without lock
pub type ImmutableMemTablesLockFree<K> = SkipMap<MemtableId, Arc<MemTable<K>>>;

/// Alias for a boolean value
pub type Bool = bool;

/// Represents an ID for a MemTable
pub type MemtableId = Vec<u8>;

/// Represents a HashSet that contains unique identifier of memtables currently being flushed
pub type MemtableFlushStream = std::collections::HashSet<MemtableId>;

/// Represents updated entries in a SkipMap after garbage collection, with a generic key type
pub type GCUpdatedEntries<K> = Arc<RwLock<SkipMap<K, SkipMapValue<ValOffset>>>>;

/// Represents value log head offset
pub type VLogHead = usize;

/// Represents value log tail offset
pub type VLogTail = usize;

/// Represents entry encoded as bytes
pub type ByteSerializedEntry = Vec<u8>;