configurable cache size

parity/cli.rs

@@ -155,6 +155,7 @@ Footprint Options:
   --cache MEGABYTES        Set total amount of discretionary memory to use for
                            the entire system, overrides other cache and queue
                            options.
+  --db-cache-size MEGABYTE Database cache size.
 
 Import/Export Options:
   --from BLOCK             Export from block BLOCK, which may be an index or
@@ -292,6 +293,7 @@ pub struct Args {
 	pub flag_ipcdisable: bool,
 	pub flag_ipcpath: Option<String>,
 	pub flag_ipcapi: Option<String>,
+	pub flag_db_cache_size: Option<usize>,
 }
 
 pub fn print_version() {

parity/configuration.rs

@@ -187,7 +187,7 @@ impl Configuration {
 		let mut latest_era = None;
 		let jdb_types = [journaldb::Algorithm::Archive, journaldb::Algorithm::EarlyMerge, journaldb::Algorithm::OverlayRecent, journaldb::Algorithm::RefCounted];
 		for i in jdb_types.into_iter() {
-			let db = journaldb::new(&append_path(&get_db_path(Path::new(&self.path()), *i, spec.genesis_header().hash()), "state"), *i);
+			let db = journaldb::new(&append_path(&get_db_path(Path::new(&self.path()), *i, spec.genesis_header().hash()), "state"), *i, None);
 			trace!(target: "parity", "Looking for best DB: {} at {:?}", i, db.latest_era());
 			match (latest_era, db.latest_era()) {
 				(Some(best), Some(this)) if best >= this => {}
@@ -214,6 +214,8 @@ impl Configuration {
 				client_config.blockchain.max_cache_size = self.args.flag_cache_max_size;
 			}
 		}
+		// forced blockchain (blocks + extras) db cache size if provided
+		client_config.blockchain.db_cache_size = self.args.flag_db_cache_size.and_then(|cs| Some(cs / 2));
 
 		client_config.tracing.enabled = match self.args.flag_tracing.as_str() {
 			"auto" => Switch::Auto,
@@ -221,6 +223,8 @@ impl Configuration {
 			"off" => Switch::Off,
 			_ => { die!("Invalid tracing method given!") }
 		};
+		// forced trace db cache size if provided
+		client_config.tracing.db_cache_size = self.args.flag_db_cache_size.and_then(|cs| Some(cs / 4));
 
 		client_config.pruning = match self.args.flag_pruning.as_str() {
 			"archive" => journaldb::Algorithm::Archive,
@@ -231,6 +235,9 @@ impl Configuration {
 			_ => { die!("Invalid pruning method given."); }
 		};
 
+		// forced state db cache size if provided
+		client_config.db_cache_size = self.args.flag_db_cache_size.and_then(|cs| Some(cs / 4));
+
 		if self.args.flag_jitvm {
 			client_config.vm_type = VMType::jit().unwrap_or_else(|| die!("Parity built without jit vm."))
 		}

parity/migration.rs

@@ -163,6 +163,7 @@ fn migrate_database(version: u32, path: PathBuf, migrations: MigrationManager) -
 		let db_config = DatabaseConfig {
 			prefix_size: None,
 			max_open_files: 64,
+			cache_size: None,
 		};
 
 		// open old database