innodb_io_patches.patch merged

buf/buf0rea.c

@@ -187,6 +187,10 @@ buf_read_ahead_random(
 	ulint		i;
 	ulint		buf_read_ahead_random_area;
 
+	if (!(srv_read_ahead & 1)) {
+		return(0);
+	}
+
 	if (srv_startup_is_before_trx_rollback_phase) {
 		/* No read-ahead to avoid thread deadlocks */
 		return(0);
@@ -412,6 +416,10 @@ buf_read_ahead_linear(
 	const ulint	buf_read_ahead_linear_area
 		= BUF_READ_AHEAD_LINEAR_AREA;
 
+ 	if (!(srv_read_ahead & 2)) {
+ 		return(0);
+ 	}
+ 
 	if (UNIV_UNLIKELY(srv_startup_is_before_trx_rollback_phase)) {
 		/* No read-ahead to avoid thread deadlocks */
 		return(0);

handler/ha_innodb.cc

@@ -137,6 +137,7 @@ static long innobase_mirrored_log_groups, innobase_log_files_in_group,
 	innobase_force_recovery, innobase_open_files,
 	innobase_autoinc_lock_mode;
 
+static unsigned long innobase_read_io_threads, innobase_write_io_threads;
 static long long innobase_buffer_pool_size, innobase_log_file_size;
 
 /* The default values for the following char* start-up parameters
@@ -2066,6 +2067,8 @@ innobase_init(
 	srv_mem_pool_size = (ulint) innobase_additional_mem_pool_size;
 
 	srv_n_file_io_threads = (ulint) innobase_file_io_threads;
+	srv_n_read_io_threads = (ulint) innobase_read_io_threads;
+	srv_n_write_io_threads = (ulint) innobase_write_io_threads;
 
 	srv_force_recovery = (ulint) innobase_force_recovery;
 
@@ -9558,6 +9561,31 @@ static MYSQL_SYSVAR_STR(version, innodb_version_str,
   PLUGIN_VAR_NOCMDOPT | PLUGIN_VAR_READONLY,
   "InnoDB version", NULL, NULL, INNODB_VERSION_STR);
 
+static MYSQL_SYSVAR_ULONG(io_capacity, srv_io_capacity,
+  PLUGIN_VAR_RQCMDARG,
+  "Number of IO operations per second the server can do. Tunes background IO rate.",
+  NULL, NULL, 100, 100, 999999999, 0);
+
+static MYSQL_SYSVAR_ULONG(read_ahead, srv_read_ahead,
+  PLUGIN_VAR_RQCMDARG,
+  "Enable/Diasable read aheads bit0:random bit1:linear",
+  NULL, NULL, 3, 0, 3, 0);
+
+static MYSQL_SYSVAR_ULONG(adaptive_checkpoint, srv_adaptive_checkpoint,
+  PLUGIN_VAR_RQCMDARG,
+  "Enable/Diasable flushing along modified age 0:disable 1:enable",
+  NULL, NULL, 0, 0, 1, 0);
+
+static MYSQL_SYSVAR_ULONG(read_io_threads, innobase_read_io_threads,
+  PLUGIN_VAR_RQCMDARG | PLUGIN_VAR_READONLY,
+  "Number of background read I/O threads in InnoDB.",
+  NULL, NULL, 1, 1, 64, 0);
+
+static MYSQL_SYSVAR_ULONG(write_io_threads, innobase_write_io_threads,
+  PLUGIN_VAR_RQCMDARG | PLUGIN_VAR_READONLY,
+  "Number of background write I/O threads in InnoDB.",
+  NULL, NULL, 1, 1, 64, 0);
+
 static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(additional_mem_pool_size),
   MYSQL_SYSVAR(autoextend_increment),
@@ -9604,6 +9632,11 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(thread_sleep_delay),
   MYSQL_SYSVAR(autoinc_lock_mode),
   MYSQL_SYSVAR(version),
+  MYSQL_SYSVAR(io_capacity),
+  MYSQL_SYSVAR(read_ahead),
+  MYSQL_SYSVAR(adaptive_checkpoint),
+  MYSQL_SYSVAR(read_io_threads),
+  MYSQL_SYSVAR(write_io_threads),
   NULL
 };
 

include/os0file.h

@@ -561,8 +561,10 @@ os_aio_init(
 /*========*/
 	ulint	n,		/* in: maximum number of pending aio operations
 				allowed; n must be divisible by n_segments */
-	ulint	n_segments,	/* in: combined number of segments in the four
-				first aio arrays; must be >= 4 */
+//	ulint	n_segments,	/* in: combined number of segments in the four
+//				first aio arrays; must be >= 4 */
+	ulint	n_read_threads,  /* n_segments == 2 + n_read_threads + n_write_threads */
+	ulint	n_write_threads, /**/
 	ulint	n_slots_sync);	/* in: number of slots in the sync aio array */
 /***********************************************************************
 Requests an asynchronous i/o operation. */

include/srv0srv.h

@@ -100,6 +100,8 @@ extern ulint	srv_mem_pool_size;
 extern ulint	srv_lock_table_size;
 
 extern ulint	srv_n_file_io_threads;
+extern ulint	srv_n_read_io_threads;
+extern ulint	srv_n_write_io_threads;
 
 #ifdef UNIV_LOG_ARCHIVE
 extern ibool	srv_log_archive_on;
@@ -144,6 +146,11 @@ extern ulong	srv_max_buf_pool_modified_pct;
 extern ulong	srv_max_purge_lag;
 
 extern ulong	srv_replication_delay;
+
+extern ulint	srv_io_capacity;
+extern ulint	srv_read_ahead;
+extern ulint	srv_adaptive_checkpoint;
+
 /*-------------------------------------------*/
 
 extern ulint	srv_n_rows_inserted;

include/sync0rw.h

@@ -328,17 +328,7 @@ rw_lock_get_x_lock_count(
 Accessor functions for rw lock. */
 UNIV_INLINE
 ulint
-rw_lock_get_s_waiters(
-/*==================*/
-	rw_lock_t*	lock);
-UNIV_INLINE
-ulint
-rw_lock_get_x_waiters(
-/*==================*/
-	rw_lock_t*	lock);
-UNIV_INLINE
-ulint
-rw_lock_get_wx_waiters(
+rw_lock_get_waiters(
 /*================*/
 	rw_lock_t*	lock);
 UNIV_INLINE
@@ -422,11 +412,6 @@ rw_lock_debug_print(
 	rw_lock_debug_t*	info);	/* in: debug struct */
 #endif /* UNIV_SYNC_DEBUG */
 
-#ifdef HAVE_GCC_ATOMIC_BUILTINS
-/* This value means NOT_LOCKED */
-#define RW_LOCK_BIAS		0x00100000
-#endif
-
 /* NOTE! The structure appears here only for the compiler to know its size.
 Do not use its fields directly! The structure used in the spin lock
 implementation of a read-write lock. Several threads may have a shared lock
@@ -436,9 +421,9 @@ blocked by readers, a writer may queue for the lock by setting the writer
 field. Then no new readers are allowed in. */
 
 struct rw_lock_struct {
-			/* Used by sync0arr.c for thread queueing */
-	os_event_t	s_event;	/* Used for s_lock */
-	os_event_t	x_event;	/* Used for x_lock */
+	os_event_t	event;	/* Used by sync0arr.c for thread queueing */
+
+#ifdef __WIN__
 	os_event_t	wait_ex_event;	/* This windows specific event is
 				used by the thread which has set the
 				lock state to RW_LOCK_WAIT_EX. The
@@ -446,34 +431,30 @@ struct rw_lock_struct {
 				thread will be the next one to proceed
 				once the current the event gets
 				signalled. See LEMMA 2 in sync0sync.c */
-
-#ifdef HAVE_GCC_ATOMIC_BUILTINS
-	volatile lint	lock_word;	/* Used by using atomic builtin */
 #endif
 
-	volatile ulint	reader_count;	/* Number of readers who have locked this
+	ulint	reader_count;	/* Number of readers who have locked this
 				lock in the shared mode */
-	volatile ulint	writer;		/* This field is set to RW_LOCK_EX if there
+	ulint	writer;		/* This field is set to RW_LOCK_EX if there
 				is a writer owning the lock (in exclusive
 				mode), RW_LOCK_WAIT_EX if a writer is
 				queueing for the lock, and
 				RW_LOCK_NOT_LOCKED, otherwise. */
-	volatile os_thread_id_t	writer_thread;
+	os_thread_id_t	writer_thread;
 				/* Thread id of a possible writer thread */
-	volatile ulint	writer_count;	/* Number of times the same thread has
+	ulint	writer_count;	/* Number of times the same thread has
 				recursively locked the lock in the exclusive
 				mode */
-#ifndef HAVE_GCC_ATOMIC_BUILTINS
 	mutex_t	mutex;		/* The mutex protecting rw_lock_struct */
-#endif
 	ulint	pass;		/* Default value 0. This is set to some
 				value != 0 given by the caller of an x-lock
 				operation, if the x-lock is to be passed to
 				another thread to unlock (which happens in
 				asynchronous i/o). */
-	volatile ulint	s_waiters;	/* 1: there are waiters (s_lock) */
-	volatile ulint	x_waiters;	/* 1: there are waiters (x_lock) */
-	volatile ulint	wait_ex_waiters;	/* 1: there are waiters (wait_ex) */
+	ulint	waiters;	/* This ulint is set to 1 if there are
+				waiters (readers or writers) in the global
+				wait array, waiting for this rw_lock.
+				Otherwise, == 0. */
 	UT_LIST_NODE_T(rw_lock_t) list;
 				/* All allocated rw locks are put into a
 				list */
@@ -486,7 +467,7 @@ struct rw_lock_struct {
 	const char*	cfile_name;/* File name where lock created */
 	const char*	last_s_file_name;/* File name where last s-locked */
 	const char*	last_x_file_name;/* File name where last x-locked */
-	volatile ibool		writer_is_wait_ex;
+	ibool		writer_is_wait_ex;
 				/* This is TRUE if the writer field is
 				RW_LOCK_WAIT_EX; this field is located far
 				from the memory update hotspot fields which

log/log0log.c

@@ -3258,6 +3258,15 @@ log_print(
 		log_sys->flushed_to_disk_lsn,
 		log_sys->last_checkpoint_lsn);
 
+	fprintf(file,
+		"Max checkpoint age  %lu\n"
+		"Modified age        %lu\n"
+		"Checkpoint age      %lu\n",
+			(ulong) log_sys->max_checkpoint_age,
+			(ulong) ut_dulint_minus(log_sys->lsn,
+					log_buf_pool_get_oldest_modification()),
+			(ulong) ut_dulint_minus(log_sys->lsn, log_sys->last_checkpoint_lsn));
+
 	current_time = time(NULL);
 
 	time_elapsed = 0.001 + difftime(current_time,

os/os0file.c

@@ -2920,8 +2920,10 @@ os_aio_init(
 /*========*/
 	ulint	n,		/* in: maximum number of pending aio operations
 				allowed; n must be divisible by n_segments */
-	ulint	n_segments,	/* in: combined number of segments in the four
-				first aio arrays; must be >= 4 */
+//	ulint	n_segments,	/* in: combined number of segments in the four
+//				first aio arrays; must be >= 4 */
+	ulint	n_read_threads,  /* n_segments == 2 + n_read_threads + n_write_threads*/
+	ulint	n_write_threads, /**/
 	ulint	n_slots_sync)	/* in: number of slots in the sync aio array */
 {
 	ulint	n_read_segs;
@@ -2929,6 +2931,8 @@ os_aio_init(
 	ulint	n_per_seg;
 	ulint	i;
 
+ 	ulint	n_segments = 2 + n_read_threads + n_write_threads;
+ 
 	ut_ad(n % n_segments == 0);
 	ut_ad(n_segments >= 4);
 
@@ -2939,8 +2943,8 @@ os_aio_init(
 	}
 
 	n_per_seg = n / n_segments;
-	n_write_segs = (n_segments - 2) / 2;
-	n_read_segs = n_segments - 2 - n_write_segs;
+	n_write_segs = n_write_threads;
+	n_read_segs = n_read_threads;
 
 	/* fprintf(stderr, "Array n per seg %lu\n", n_per_seg); */
 
@@ -3140,6 +3144,13 @@ os_aio_array_reserve_slot(
 	OVERLAPPED*	control;
 #endif
 	ulint		i;
+	ulint		prim_segment;
+	ulint		n;
+
+	n = array->n_slots / array->n_segments;
+	/* 64 blocks' striping ( aligning max(BUF_READ_AHEAD_AREA) ) */
+	prim_segment = ( offset >> (UNIV_PAGE_SIZE_SHIFT + 6) ) % (array->n_segments);
+
 loop:
 	os_mutex_enter(array->mutex);
 
@@ -3158,6 +3169,16 @@ os_aio_array_reserve_slot(
 		goto loop;
 	}
 
+	for (i = prim_segment * n; i < array->n_slots; i++) {
+		slot = os_aio_array_get_nth_slot(array, i);
+
+		if (slot->reserved == FALSE) {
+			break;
+		}
+	}
+
+	if (slot->reserved == TRUE){
+		/* Not found after the intended segment. So we should search before. */
 	for (i = 0;; i++) {
 		slot = os_aio_array_get_nth_slot(array, i);
 
@@ -3165,6 +3186,7 @@ os_aio_array_reserve_slot(
 			break;
 		}
 	}
+	}
 
 	array->n_reserved++;
 

srv/srv0srv.c

@@ -147,6 +147,8 @@ UNIV_INTERN ulint	srv_mem_pool_size	= ULINT_MAX;
 UNIV_INTERN ulint	srv_lock_table_size	= ULINT_MAX;
 
 UNIV_INTERN ulint	srv_n_file_io_threads	= ULINT_MAX;
+ulint	srv_n_read_io_threads	= 1;
+ulint	srv_n_write_io_threads	= 1;
 
 #ifdef UNIV_LOG_ARCHIVE
 UNIV_INTERN ibool		srv_log_archive_on	= FALSE;
@@ -311,6 +313,15 @@ UNIV_INTERN int	srv_query_thread_priority = 0;
 
 UNIV_INTERN ulong	srv_replication_delay		= 0;
 
+ulint	srv_io_capacity = 100;
+
+/* Returns the number of IO operations that is X percent of the capacity.
+PCT_IO(5) -> returns the number of IO operations that is 5% of the max
+where max is srv_io_capacity. */
+#define PCT_IO(pct) ((ulint) (srv_io_capacity * ((double) pct / 100.0)))
+
+ulint	srv_read_ahead = 3; /* 1: random  2: linear  3: Both */
+ulint	srv_adaptive_checkpoint = 0; /* 0:disable 1:enable */
 /*-------------------------------------------*/
 UNIV_INTERN ulong	srv_n_spin_wait_rounds	= 20;
 UNIV_INTERN ulong	srv_n_free_tickets_to_enter = 500;
@@ -2203,6 +2214,8 @@ srv_master_thread(
 	ibool		skip_sleep	= FALSE;
 	ulint		i;
 
+	dulint		oldest_lsn;
+	
 #ifdef UNIV_DEBUG_THREAD_CREATION
 	fprintf(stderr, "Master thread starts, id %lu\n",
 		os_thread_pf(os_thread_get_curr_id()));
@@ -2293,7 +2306,7 @@ srv_master_thread(
 		if (n_pend_ios < 3 && (n_ios - n_ios_old < 5)) {
 			srv_main_thread_op_info = "doing insert buffer merge";
 			ibuf_contract_for_n_pages(
-				TRUE, srv_insert_buffer_batch_size / 4);
+				TRUE, PCT_IO((srv_insert_buffer_batch_size / 4)));
 
 			srv_main_thread_op_info = "flushing log";
 
@@ -2306,7 +2319,7 @@ srv_master_thread(
 			/* Try to keep the number of modified pages in the
 			buffer pool under the limit wished by the user */
 
-			n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100,
+ 			n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(100),
 							  IB_ULONGLONG_MAX);
 
 			/* If we had to do the flush, it may have taken
@@ -2315,6 +2328,44 @@ srv_master_thread(
 			iteration of this loop. */
 
 			skip_sleep = TRUE;
+		} else if (srv_adaptive_checkpoint) {
+
+			/* Try to keep modified age not to exceed
+			max_checkpoint_age * 7/8 line */
+
+			mutex_enter(&(log_sys->mutex));
+
+			oldest_lsn = buf_pool_get_oldest_modification();
+			if (ut_dulint_is_zero(oldest_lsn)) {
+
+				mutex_exit(&(log_sys->mutex));
+
+			} else {
+				if (ut_dulint_minus(log_sys->lsn, oldest_lsn)
+				    > (log_sys->max_checkpoint_age) - ((log_sys->max_checkpoint_age) / 4)) {
+
+					/* 2nd defence line (max_checkpoint_age * 3/4) */
+
+					mutex_exit(&(log_sys->mutex));
+
+					n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(100),
+									  ut_dulint_max);
+					skip_sleep = TRUE;
+				} else if (ut_dulint_minus(log_sys->lsn, oldest_lsn)
+					   > (log_sys->max_checkpoint_age)/2 ) {
+
+					/* 1st defence line (max_checkpoint_age * 1/2) */
+
+					mutex_exit(&(log_sys->mutex));
+
+					n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(10),
+									  ut_dulint_max);
+					skip_sleep = TRUE;
+				} else {
+					mutex_exit(&(log_sys->mutex));
+				}
+			}
+
 		}
 
 		if (srv_activity_count == old_activity_count) {
@@ -2341,10 +2392,10 @@ srv_master_thread(
 	n_pend_ios = buf_get_n_pending_ios() + log_sys->n_pending_writes;
 	n_ios = log_sys->n_log_ios + buf_pool->n_pages_read
 		+ buf_pool->n_pages_written;
-	if (n_pend_ios < 3 && (n_ios - n_ios_very_old < 200)) {
-
-		srv_main_thread_op_info = "flushing buffer pool pages";
-		buf_flush_batch(BUF_FLUSH_LIST, 100, IB_ULONGLONG_MAX);
+ 	if (n_pend_ios < 3 && (n_ios - n_ios_very_old < PCT_IO(200))) {
+  
+  		srv_main_thread_op_info = "flushing buffer pool pages";
+ 		buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(100), IB_ULONGLONG_MAX);
 
 		srv_main_thread_op_info = "flushing log";
 		log_buffer_flush_to_disk();
@@ -2354,7 +2405,7 @@ srv_master_thread(
 	even if the server were active */
 
 	srv_main_thread_op_info = "doing insert buffer merge";
-	ibuf_contract_for_n_pages(TRUE, srv_insert_buffer_batch_size / 4);
+	ibuf_contract_for_n_pages(TRUE, PCT_IO((srv_insert_buffer_batch_size / 4)));
 
 	srv_main_thread_op_info = "flushing log";
 	log_buffer_flush_to_disk();
@@ -2394,14 +2445,14 @@ srv_master_thread(
 		(> 70 %), we assume we can afford reserving the disk(s) for
 		the time it requires to flush 100 pages */
 
-		n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100,
+ 	        n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(100),
 						  IB_ULONGLONG_MAX);
 	} else {
 		/* Otherwise, we only flush a small number of pages so that
 		we do not unnecessarily use much disk i/o capacity from
 		other work */
 
-		n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 10,
+ 	        n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(10),
 						  IB_ULONGLONG_MAX);
 	}
 
@@ -2489,7 +2540,7 @@ srv_master_thread(
 		n_bytes_merged = 0;
 	} else {
 		n_bytes_merged = ibuf_contract_for_n_pages(
-			TRUE, srv_insert_buffer_batch_size);
+			TRUE, PCT_IO((srv_insert_buffer_batch_size * 5)));
 	}
 
 	srv_main_thread_op_info = "reserving kernel mutex";
@@ -2505,7 +2556,7 @@ srv_master_thread(
 	srv_main_thread_op_info = "flushing buffer pool pages";
 
 	if (srv_fast_shutdown < 2) {
-		n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100,
+ 	        n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, PCT_IO(100),
 						  IB_ULONGLONG_MAX);
 	} else {
 		/* In the fastest shutdown we do not flush the buffer pool

srv/srv0start.c

@@ -1204,24 +1204,28 @@ innobase_start_or_create_for_mysql(void)
 		return(DB_ERROR);
 	}
 
+	/* over write innodb_file_io_threads */
+	srv_n_file_io_threads = 2 + srv_n_read_io_threads + srv_n_write_io_threads;
+
 	/* Restrict the maximum number of file i/o threads */
 	if (srv_n_file_io_threads > SRV_MAX_N_IO_THREADS) {
 
 		srv_n_file_io_threads = SRV_MAX_N_IO_THREADS;
+		srv_n_read_io_threads = srv_n_write_io_threads = (SRV_MAX_N_IO_THREADS - 2) / 2;
 	}
 
 	if (!os_aio_use_native_aio) {
 		/* In simulated aio we currently have use only for 4 threads */
-		srv_n_file_io_threads = 4;
+		/*srv_n_file_io_threads = 4;*/
 
 		os_aio_init(8 * SRV_N_PENDING_IOS_PER_THREAD
 			    * srv_n_file_io_threads,
-			    srv_n_file_io_threads,
-			    SRV_MAX_N_PENDING_SYNC_IOS);
+			    srv_n_read_io_threads, srv_n_write_io_threads,
+			    SRV_MAX_N_PENDING_SYNC_IOS * 8);
 	} else {
 		os_aio_init(SRV_N_PENDING_IOS_PER_THREAD
 			    * srv_n_file_io_threads,
-			    srv_n_file_io_threads,
+			    srv_n_read_io_threads, srv_n_write_io_threads,
 			    SRV_MAX_N_PENDING_SYNC_IOS);
 	}
 

sync/sync0arr.c

@@ -307,13 +307,13 @@ sync_cell_event_reset(
 {
 	if (type == SYNC_MUTEX) {
 		return(os_event_reset(((mutex_t *) object)->event));
+#ifdef __WIN__
 	} else if (type == RW_LOCK_WAIT_EX) {
 		return(os_event_reset(
 		       ((rw_lock_t *) object)->wait_ex_event));
-	} else if (type == RW_LOCK_SHARED) {
-		return(os_event_reset(((rw_lock_t *) object)->s_event));
-	} else { /* RW_LOCK_EX */
-		return(os_event_reset(((rw_lock_t *) object)->x_event));
+#endif
+	} else {
+		return(os_event_reset(((rw_lock_t *) object)->event));
 	}
 }
 
@@ -413,12 +413,15 @@ sync_array_wait_event(
 
 	if (cell->request_type == SYNC_MUTEX) {
 		event = ((mutex_t*) cell->wait_object)->event;
+#ifdef __WIN__
+	/* On windows if the thread about to wait is the one which
+	has set the state of the rw_lock to RW_LOCK_WAIT_EX, then
+	it waits on a special event i.e.: wait_ex_event. */
 	} else if (cell->request_type == RW_LOCK_WAIT_EX) {
 		event = ((rw_lock_t*) cell->wait_object)->wait_ex_event;
-	} else if (cell->request_type == RW_LOCK_SHARED) {
-		event = ((rw_lock_t*) cell->wait_object)->s_event;
+#endif
 	} else {
-		event = ((rw_lock_t*) cell->wait_object)->x_event;
+		event = ((rw_lock_t*) cell->wait_object)->event;
 	}
 
 		cell->waiting = TRUE;
@@ -459,7 +462,6 @@ sync_array_cell_print(
 	mutex_t*	mutex;
 	rw_lock_t*	rwlock;
 	ulint		type;
-	ulint		writer;
 
 	type = cell->request_type;
 
@@ -489,10 +491,12 @@ sync_array_cell_print(
 			(ulong) mutex->waiters);
 
 	} else if (type == RW_LOCK_EX
+#ifdef __WIN__
 		   || type == RW_LOCK_WAIT_EX
+#endif
 		   || type == RW_LOCK_SHARED) {
 
-		fputs(type == RW_LOCK_SHARED ? "S-lock on" : "X-lock on", file);
+		fputs(type == RW_LOCK_EX ? "X-lock on" : "S-lock on", file);
 
 		rwlock = cell->old_wait_rw_lock;
 
@@ -500,24 +504,22 @@ sync_array_cell_print(
 			" RW-latch at %p created in file %s line %lu\n",
 			(void*) rwlock, rwlock->cfile_name,
 			(ulong) rwlock->cline);
-		writer = rw_lock_get_writer(rwlock);
-		if (writer != RW_LOCK_NOT_LOCKED) {
+		if (rwlock->writer != RW_LOCK_NOT_LOCKED) {
 			fprintf(file,
 				"a writer (thread id %lu) has"
 				" reserved it in mode %s",
 				(ulong) os_thread_pf(rwlock->writer_thread),
-				writer == RW_LOCK_EX
+				rwlock->writer == RW_LOCK_EX
 				? " exclusive\n"
 				: " wait exclusive\n");
 		}
 
 		fprintf(file,
-			"number of readers %lu, s_waiters flag %lu, x_waiters flag %lu\n"
+			"number of readers %lu, waiters flag %lu\n"
 			"Last time read locked in file %s line %lu\n"
 			"Last time write locked in file %s line %lu\n",
 			(ulong) rwlock->reader_count,
-			(ulong) rwlock->s_waiters,
-			(ulong) (rwlock->x_waiters || rwlock->wait_ex_waiters),
+			(ulong) rwlock->waiters,
 			rwlock->last_s_file_name,
 			(ulong) rwlock->last_s_line,
 			rwlock->last_x_file_name,
@@ -842,15 +844,11 @@ sync_array_object_signalled(
 /*========================*/
 	sync_array_t*	arr)	/* in: wait array */
 {
-#ifdef HAVE_GCC_ATOMIC_BUILTINS
-	__sync_fetch_and_add(&(arr->sg_count),1);
-#else
 	sync_array_enter(arr);
 
 	arr->sg_count++;
 
 	sync_array_exit(arr);
-#endif
 }
 
 /**************************************************************************
@@ -891,23 +889,19 @@ sync_arr_wake_threads_if_sema_free(void)
 
 					mutex = cell->wait_object;
 					os_event_set(mutex->event);
+#ifdef __WIN__
 				} else if (cell->request_type
 					   == RW_LOCK_WAIT_EX) {
 					rw_lock_t*	lock;
 
 					lock = cell->wait_object;
 					os_event_set(lock->wait_ex_event);
-				} else if (cell->request_type
-					   == RW_LOCK_SHARED) {
-					rw_lock_t*	lock;
-
-					lock = cell->wait_object;
-					os_event_set(lock->s_event);
+#endif
 				} else {
-					rw_lock_t*      lock;
+					rw_lock_t*	lock;
 
 					lock = cell->wait_object;
-					os_event_set(lock->x_event);
+					os_event_set(lock->event);
 				}
 			}
 		}