Add LRU cache to database (#837)

* Add LRU caches to store

* Improvements to LRU caches

* Take state by value in `Store::put_state`

* Store blocks by value, configurable cache sizes

* Use a StateBatch to efficiently store skip states

* Fix store tests

* Add CloneConfig test, remove unused metrics

* Use Mutexes instead of RwLocks for LRU caches

beacon_node/client/src/builder.rs

@@ -7,7 +7,7 @@ use beacon_chain::{
     slot_clock::{SlotClock, SystemTimeSlotClock},
     store::{
         migrate::{BackgroundMigrator, Migrate, NullMigrator},
-        DiskStore, MemoryStore, SimpleDiskStore, Store,
+        DiskStore, MemoryStore, SimpleDiskStore, Store, StoreConfig,
     },
     BeaconChain, BeaconChainTypes, Eth1ChainBackend, EventHandler,
 };
@@ -478,7 +478,7 @@ where
         mut self,
         hot_path: &Path,
         cold_path: &Path,
-        slots_per_restore_point: u64,
+        config: StoreConfig,
     ) -> Result<Self, String> {
         let context = self
             .runtime_context
@@ -490,14 +490,8 @@ where
             .clone()
             .ok_or_else(|| "disk_store requires a chain spec".to_string())?;
 
-        let store = DiskStore::open(
-            hot_path,
-            cold_path,
-            slots_per_restore_point,
-            spec,
-            context.log,
-        )
-        .map_err(|e| format!("Unable to open database: {:?}", e))?;
+        let store = DiskStore::open(hot_path, cold_path, config, spec, context.log)
+            .map_err(|e| format!("Unable to open database: {:?}", e))?;
         self.store = Some(Arc::new(store));
         Ok(self)
     }

beacon_node/client/src/config.rs

@@ -6,6 +6,9 @@ use std::path::PathBuf;
 /// The number initial validators when starting the `Minimal`.
 const TESTNET_SPEC_CONSTANTS: &str = "minimal";
 
+/// Default directory name for the freezer database under the top-level data dir.
+const DEFAULT_FREEZER_DB_DIR: &str = "freezer_db";
+
 /// Defines how the client should initialize the `BeaconChain` and other components.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub enum ClientGenesis {
@@ -41,6 +44,10 @@ impl Default for ClientGenesis {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
     pub data_dir: PathBuf,
+    /// Name of the directory inside the data directory where the main "hot" DB is located.
+    pub db_name: String,
+    /// Path where the freezer database will be located.
+    pub freezer_db_path: Option<PathBuf>,
     pub testnet_dir: Option<PathBuf>,
     pub log_file: PathBuf,
     pub spec_constants: String,
@@ -64,6 +71,8 @@ impl Default for Config {
     fn default() -> Self {
         Self {
             data_dir: PathBuf::from(".lighthouse"),
+            db_name: "chain_db".to_string(),
+            freezer_db_path: None,
             testnet_dir: None,
             log_file: PathBuf::from(""),
             genesis: <_>::default(),
@@ -83,7 +92,7 @@ impl Config {
     /// Get the database path without initialising it.
     pub fn get_db_path(&self) -> Option<PathBuf> {
         self.get_data_dir()
-            .map(|data_dir| data_dir.join(&self.store.db_name))
+            .map(|data_dir| data_dir.join(&self.db_name))
     }
 
     /// Get the database path, creating it if necessary.
@@ -97,7 +106,7 @@ impl Config {
     /// Fetch default path to use for the freezer database.
     fn default_freezer_db_path(&self) -> Option<PathBuf> {
         self.get_data_dir()
-            .map(|data_dir| data_dir.join(self.store.default_freezer_db_dir()))
+            .map(|data_dir| data_dir.join(DEFAULT_FREEZER_DB_DIR))
     }
 
     /// Returns the path to which the client may initialize the on-disk freezer database.
@@ -105,8 +114,7 @@ impl Config {
     /// Will attempt to use the user-supplied path from e.g. the CLI, or will default
     /// to a directory in the data_dir if no path is provided.
     pub fn get_freezer_db_path(&self) -> Option<PathBuf> {
-        self.store
-            .freezer_db_path
+        self.freezer_db_path
             .clone()
             .or_else(|| self.default_freezer_db_path())
     }