max subcompactions (#36)

librocksdb_sys/crocksdb/c.cc

@@ -1489,6 +1489,9 @@ void crocksdb_options_set_block_based_table_factory(
   }
 }
 
+void crocksdb_options_set_max_subcompactions(crocksdb_options_t *opt, size_t v) {
+  opt->rep.max_subcompactions = v;
+}
 
 crocksdb_cuckoo_table_options_t*
 crocksdb_cuckoo_options_create() {

librocksdb_sys/crocksdb/rocksdb/c.h

@@ -775,6 +775,8 @@ extern C_ROCKSDB_LIBRARY_API void crocksdb_options_set_report_bg_io_stats(
     crocksdb_options_t*, int);
 extern C_ROCKSDB_LIBRARY_API void crocksdb_options_set_compaction_readahead_size(
     crocksdb_options_t*, size_t);
+extern C_ROCKSDB_LIBRARY_API void crocksdb_options_set_max_subcompactions(
+    crocksdb_options_t*, size_t);
 
 enum {
   crocksdb_tolerate_corrupted_tail_records_recovery = 0,

librocksdb_sys/src/lib.rs

@@ -257,6 +257,7 @@ extern "C" {
     pub fn crocksdb_options_set_report_bg_io_stats(options: *mut DBOptions, v: c_int);
     pub fn crocksdb_options_set_compaction_readahead_size(options: *mut DBOptions, v: size_t);
     pub fn crocksdb_options_set_wal_recovery_mode(options: *mut DBOptions, mode: DBRecoveryMode);
+    pub fn crocksdb_options_set_max_subcompactions(options: *mut DBOptions, v: size_t);
     pub fn crocksdb_options_enable_statistics(options: *mut DBOptions);
     pub fn crocksdb_options_statistics_get_string(options: *mut DBOptions) -> *const c_char;
     pub fn crocksdb_options_statistics_get_ticker_count(options: *mut DBOptions,

src/rocksdb_options.rs

@@ -542,6 +542,12 @@ impl Options {
         }
     }
 
+    pub fn set_max_subcompactions(&mut self, n: usize) {
+        unsafe {
+            crocksdb_ffi::crocksdb_options_set_max_subcompactions(self.inner, n);
+        }
+    }
+
     pub fn set_disable_auto_compactions(&mut self, disable: bool) {
         unsafe {
             if disable {

tests/test_rocksdb_options.rs

@@ -203,3 +203,12 @@ fn test_pending_compaction_bytes_limit() {
     opts.set_hard_pending_compaction_bytes_limit(256 * 1024 * 1024 * 1024);
     let db = DB::open(opts, path.path().to_str().unwrap()).unwrap();
 }
+
+#[test]
+fn test_set_max_subcompactions() {
+    let path = TempDir::new("_rust_rocksdb_max_subcompactions").expect("");
+    let mut opts = Options::new();
+    opts.create_if_missing(true);
+    opts.set_max_subcompactions(4);
+    DB::open(opts, path.path().to_str().unwrap()).unwrap();
+}