Experimental code that uses one locker ID per thread. Seems to work OK,

is enabled by default. #undef BDB_REUSE_LOCKERS in back-bdb.h to disable.
Probably needs to be disabled when built with NO_THREADS.

diff --git a/servers/slapd/back-bdb/back-bdb.h b/servers/slapd/back-bdb/back-bdb.h
index 6eeae509e586c3f66085c920a8e71d5a75ddc774..2d7075b9931d1143eb6046400700d83671eea046 100644 (file)
--- a/servers/slapd/back-bdb/back-bdb.h
+++ b/servers/slapd/back-bdb/back-bdb.h
@@ -156,8 +156,8 @@ struct bdb_op_info {
 #define TXN_COMMIT(txn,f)                      txn_commit((txn), (f))
 #define        TXN_ABORT(txn)                          txn_abort((txn))
 #define TXN_ID(txn)                                    txn_id(txn)
-#define LOCK_ID(env, locker)           lock_id(env, locker)
-#define LOCK_ID_FREE(env, locker)      lock_id_free(env, locker)
+#define XLOCK_ID(env, locker)          lock_id(env, locker)
+#define XLOCK_ID_FREE(env, locker)     lock_id_free(env, locker)
 #else
 #define LOCK_DETECT(env,f,t,a)         (env)->lock_detect(env, f, t, a)
 #define LOCK_GET(env,i,f,o,m,l)                (env)->lock_get(env, i, f, o, m, l)
@@ -168,8 +168,18 @@ struct bdb_op_info {
 #define TXN_COMMIT(txn,f)                      (txn)->commit((txn), (f))
 #define TXN_ABORT(txn)                         (txn)->abort((txn))
 #define TXN_ID(txn)                                    (txn)->id(txn)
-#define LOCK_ID(env, locker)           (env)->lock_id(env, locker)
-#define LOCK_ID_FREE(env, locker)      (env)->lock_id_free(env, locker)
+#define XLOCK_ID(env, locker)          (env)->lock_id(env, locker)
+#define XLOCK_ID_FREE(env, locker)     (env)->lock_id_free(env, locker)
+
+#define BDB_REUSE_LOCKERS
+
+#ifdef BDB_REUSE_LOCKERS
+#define        LOCK_ID_FREE(env, locker)
+#define        LOCK_ID(env, locker)    bdb_locker_id(op, env, locker)
+#else
+#define        LOCK_ID_FREE(env, locker)       XLOCK_ID_FREE(env, locker)
+#define        LOCK_ID(env, locker)            XLOCK_ID(env, locker)
+#endif
 
 #if DB_VERSION_MINOR > 1 || DB_VERSION_PATCH >= 17
 #undef DB_OPEN

diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 8f20bcee6ff0f1b9559a3a91b98d3d7f815cc12d..dcfa51c68e5dd63db08d195fe32799dd55594913 100644 (file)
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -1100,3 +1100,57 @@ bdb_lru_print( Cache *cache )
        }
 }
 #endif
+
+#ifdef BDB_REUSE_LOCKERS
+void
+bdb_locker_id_free( void *key, void *data )
+{
+       DB_ENV *env = key;
+       int lockid = (int) data;
+
+       XLOCK_ID_FREE( env, lockid );
+}
+
+int
+bdb_locker_id( Operation *op, DB_ENV *env, int *locker )
+{
+       int i, rc, lockid;
+       void *data;
+
+       if ( !env || !op || !locker ) return -1;
+
+       /* Shouldn't happen unless we're single-threaded */
+       if ( !op->o_threadctx ) {
+               *locker = 0;
+               return 0;
+       }
+
+       if ( ldap_pvt_thread_pool_getkey( op->o_threadctx, env, &data, NULL ) ) {
+               for ( i=0, rc=1; rc != 0 && i<4; i++ ) {
+                       rc = XLOCK_ID( env, &lockid );
+                       if (rc) ldap_pvt_thread_yield();
+               }
+               if ( rc != 0) {
+                       return rc;
+               }
+               data = (void *)lockid;
+               if ( ( rc = ldap_pvt_thread_pool_setkey( op->o_threadctx, env,
+                       data, bdb_locker_id_free ) ) ) {
+                       XLOCK_ID_FREE( env, lockid );
+#ifdef NEW_LOGGING
+                       LDAP_LOG( BACK_BDB, ERR, "bdb_locker_id: err %s(%d)\n",
+                               db_strerror(rc), rc, 0 );
+#else
+                       Debug( LDAP_DEBUG_ANY, "bdb_locker_id: err %s(%d)\n",
+                               db_strerror(rc), rc, 0 );
+#endif
+
+                       return rc;
+               }
+       } else {
+               lockid = (int)data;
+       }
+       *locker = lockid;
+       return 0;
+}
+#endif

diff --git a/servers/slapd/back-bdb/proto-bdb.h b/servers/slapd/back-bdb/proto-bdb.h
index 6cef37e39c57fa2b7433f4b9a0ef2ccb2d5b2405..1a50eef2beb931e114c696523cffdd825d7dffc7 100644 (file)
--- a/servers/slapd/back-bdb/proto-bdb.h
+++ b/servers/slapd/back-bdb/proto-bdb.h
@@ -343,6 +343,12 @@ int bdb_cache_delete_entry(
 );
 void bdb_cache_release_all( Cache *cache );
 
+#ifdef BDB_REUSE_LOCKERS
+
+int bdb_locker_id( Operation *op, DB_ENV *env, int *locker );
+
+#endif
+
 #ifdef HAVE_EBCDIC
 char *ebcdic_dberror( int rc );