Merge pull request #113 from mempool/junderw/read-only-script-gen

Use read only when opening the history DB for popular scripts binary

src/bin/popular-scripts.rs

@@ -18,7 +18,10 @@ type DB = rocksdb::DBWithThreadMode<rocksdb::MultiThreaded>;
 lazy_static! {
     static ref HISTORY_DB: DB = {
         let config = Config::from_args();
-        open_raw_db(&config.db_path.join("newindex").join("history"))
+        open_raw_db(
+            &config.db_path.join("newindex").join("history"),
+            electrs::new_index::db::OpenMode::ReadOnly,
+        )
     };
 }
 

src/new_index/db.rs

@@ -148,7 +148,7 @@ pub enum DBFlush {
 impl DB {
     pub fn open(path: &Path, config: &Config) -> DB {
         let db = DB {
-            db: open_raw_db(path),
+            db: open_raw_db(path, OpenMode::ReadWrite),
         };
         db.verify_compatibility(config);
         db
@@ -290,7 +290,17 @@ impl DB {
     }
 }
 
-pub fn open_raw_db<T: rocksdb::ThreadMode>(path: &Path) -> rocksdb::DBWithThreadMode<T> {
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(u8)]
+pub enum OpenMode {
+    ReadOnly,
+    ReadWrite,
+}
+
+pub fn open_raw_db<T: rocksdb::ThreadMode>(
+    path: &Path,
+    read_mode: OpenMode,
+) -> rocksdb::DBWithThreadMode<T> {
     debug!("opening DB at {:?}", path);
     let mut db_opts = rocksdb::Options::default();
     db_opts.create_if_missing(true);
@@ -308,5 +318,13 @@ pub fn open_raw_db<T: rocksdb::ThreadMode>(path: &Path) -> rocksdb::DBWithThread
     // let mut block_opts = rocksdb::BlockBasedOptions::default();
     // block_opts.set_block_size(???);
 
-    rocksdb::DBWithThreadMode::<T>::open(&db_opts, path).expect("failed to open RocksDB")
+    match read_mode {
+        OpenMode::ReadOnly => {
+            rocksdb::DBWithThreadMode::<T>::open_for_read_only(&db_opts, path, false)
+                .expect("failed to open RocksDB (READ ONLY)")
+        }
+        OpenMode::ReadWrite => {
+            rocksdb::DBWithThreadMode::<T>::open(&db_opts, path).expect("failed to open RocksDB")
+        }
+    }
 }

start

@@ -88,7 +88,6 @@ POPULAR_SCRIPTS_FILE="${POPULAR_SCRIPTS_FOLDER}/popular-scripts.txt"
 # This function runs the job for generating the popular scripts text file for the precache arg
 generate_popular_scripts() {
 	mkdir -p "${POPULAR_SCRIPTS_FOLDER}"
-	rm -f "${POPULAR_SCRIPTS_FILE_RAW}" "${POPULAR_SCRIPTS_FILE}"
 
 	## Use nproc * 4 threads to generate the txt file (lots of iowait, so 2x~4x core count is ok)
 	## Only pick up addresses with 101 history events or more
@@ -107,8 +106,12 @@ generate_popular_scripts() {
 		--db-dir "${DB_FOLDER}" \
 		> "${POPULAR_SCRIPTS_FILE_RAW}"
 
-	## Sorted and deduplicated just in case
-	sort "${POPULAR_SCRIPTS_FILE_RAW}" | uniq > "${POPULAR_SCRIPTS_FILE}"
+	## Only overwrite the existing file if the popular-scripts cargo run succeeded
+	if [ "$?" = "0" ];then
+		## Sorted and deduplicated just in case
+		sort "${POPULAR_SCRIPTS_FILE_RAW}" | uniq > "${POPULAR_SCRIPTS_FILE}"
+	fi
+
 	rm "${POPULAR_SCRIPTS_FILE_RAW}"
 }