Sync with rev. 107

handler/ha_innodb.cc

@@ -206,6 +206,7 @@ static my_bool	innobase_use_doublewrite		= TRUE;
 static my_bool	innobase_use_checksums			= TRUE;
 static my_bool	innobase_extra_undoslots		= FALSE;
 static my_bool	innobase_fast_recovery			= FALSE;
+static my_bool	innobase_use_purge_thread		= FALSE;
 static my_bool	innobase_locks_unsafe_for_binlog	= FALSE;
 static my_bool	innobase_overwrite_relay_log_info	= FALSE;
 static my_bool	innobase_rollback_on_timeout		= FALSE;
@@ -2293,6 +2294,8 @@ innobase_init(
 
 	srv_fast_recovery = (ibool) innobase_fast_recovery;
 
+	srv_use_purge_thread = (ibool) innobase_use_purge_thread;
+
 	srv_use_doublewrite_buf = (ibool) innobase_use_doublewrite;
 	srv_use_checksums = (ibool) innobase_use_checksums;
 
@@ -7268,7 +7271,7 @@ ha_innobase::info(
 		We do not update delete_length if no locking is requested
 		so the "old" value can remain. delete_length is initialized
 		to 0 in the ha_statistics' constructor. */
-		if (!(flag & HA_STATUS_NO_LOCK)) {
+		if (!(flag & HA_STATUS_NO_LOCK) && srv_stats_update_need_lock) {
 
 			/* lock the data dictionary to avoid races with
 			ibd_file_missing and tablespace_discarded */
@@ -9934,6 +9937,11 @@ static MYSQL_SYSVAR_BOOL(fast_recovery, innobase_fast_recovery,
   "Enable to use speed hack of recovery avoiding flush list sorting.",
   NULL, NULL, FALSE);
 
+static MYSQL_SYSVAR_BOOL(use_purge_thread, innobase_use_purge_thread,
+  PLUGIN_VAR_NOCMDARG | PLUGIN_VAR_READONLY,
+  "Enable to use purge devoted thread.",
+  NULL, NULL, FALSE);
+
 static MYSQL_SYSVAR_BOOL(overwrite_relay_log_info, innobase_overwrite_relay_log_info,
   PLUGIN_VAR_NOCMDARG | PLUGIN_VAR_READONLY,
   "During InnoDB crash recovery on slave overwrite relay-log.info "
@@ -10081,6 +10089,12 @@ static MYSQL_SYSVAR_ULONG(stats_auto_update, srv_stats_auto_update,
   "(except for ANALYZE TABLE command) 0:disable 1:enable",
   NULL, NULL, 1, 0, 1, 0);
 
+static MYSQL_SYSVAR_ULONG(stats_update_need_lock, srv_stats_update_need_lock,
+  PLUGIN_VAR_RQCMDARG,
+  "Enable/Disable InnoDB's update statistics which needs to lock dictionary. "
+  "e.g. Data_free.",
+  NULL, NULL, 1, 0, 1, 0);
+
 static MYSQL_SYSVAR_BOOL(adaptive_hash_index, btr_search_enabled,
   PLUGIN_VAR_OPCMDARG,
   "Enable InnoDB adaptive hash index (enabled by default).  "
@@ -10325,7 +10339,7 @@ static MYSQL_SYSVAR_ULONG(expand_import, srv_expand_import,
 static MYSQL_SYSVAR_ULONG(extra_rsegments, srv_extra_rsegments,
   PLUGIN_VAR_RQCMDARG | PLUGIN_VAR_READONLY,
   "Number of extra user rollback segments when create new database.",
-  NULL, NULL, 0, 0, 127, 0);
+  NULL, NULL, 0, 0, 126, 0);
 
 static MYSQL_SYSVAR_ULONG(dict_size_limit, srv_dict_size_limit,
   PLUGIN_VAR_RQCMDARG,
@@ -10374,6 +10388,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(stats_on_metadata),
   MYSQL_SYSVAR(stats_method),
   MYSQL_SYSVAR(stats_auto_update),
+  MYSQL_SYSVAR(stats_update_need_lock),
   MYSQL_SYSVAR(stats_sample_pages),
   MYSQL_SYSVAR(adaptive_hash_index),
   MYSQL_SYSVAR(replication_delay),
@@ -10404,6 +10419,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(change_buffering),
   MYSQL_SYSVAR(read_ahead_threshold),
   MYSQL_SYSVAR(io_capacity),
+  MYSQL_SYSVAR(use_purge_thread),
   NULL
 };
 

handler/innodb_patch_info.h

@@ -37,5 +37,6 @@ struct innodb_enhancement {
 {"innodb_split_buf_pool_mutex","More fix of buffer_pool mutex","Spliting buf_pool_mutex and optimizing based on innodb_opt_lru_count","http://www.percona.com/docs/wiki/percona-xtradb"},
 {"innodb_stats","Additional features about InnoDB statistics/optimizer","","http://www.percona.com/docs/wiki/percona-xtradb"},
 {"innodb_recovery_patches","Bugfixes and adjustments about recovery process","","http://www.percona.com/docs/wiki/percona-xtradb"},
+{"innodb_purge_thread","Enable to use purge devoted thread","","http://www.percona.com/docs/wiki/percona-xtradb"},
 {NULL, NULL, NULL, NULL}
 };

include/srv0srv.h

@@ -134,6 +134,8 @@ extern ibool	srv_extra_undoslots;
 
 extern ibool	srv_fast_recovery;
 
+extern ibool	srv_use_purge_thread;
+
 extern ibool	srv_auto_extend_last_data_file;
 extern ulint	srv_last_file_size_max;
 extern char**	srv_log_group_home_dirs;
@@ -217,6 +219,7 @@ extern ulint	srv_stats_method;
 #define SRV_STATS_METHOD_NULLS_NOT_EQUAL 1
 #define SRV_STATS_METHOD_IGNORE_NULLS    2
 extern ulint	srv_stats_auto_update;
+extern ulint	srv_stats_update_need_lock;
 
 extern ibool	srv_use_doublewrite_buf;
 extern ibool	srv_use_checksums;
@@ -424,6 +427,7 @@ enum srv_thread_type {
 	SRV_RECOVERY,	/**< threads finishing a recovery */
 	SRV_INSERT,	/**< thread flushing the insert buffer to disk */
 #endif
+	SRV_PURGE,	/* thread purging undo records */
 	SRV_MASTER	/**< the master thread, (whose type number must
 			be biggest) */
 };
@@ -497,6 +501,14 @@ srv_master_thread(
 /*==============*/
 	void*	arg);	/*!< in: a dummy parameter required by
 			os_thread_create */
+/*************************************************************************
+The undo purge thread. */
+UNIV_INTERN
+os_thread_ret_t
+srv_purge_thread(
+/*=============*/
+	void*	arg);	/* in: a dummy parameter required by
+			os_thread_create */
 /*******************************************************************//**
 Tells the Innobase server that there has been activity in the database
 and wakes up the master thread if it is suspended (not sleeping). Used

srv/srv0srv.c

@@ -162,6 +162,8 @@ UNIV_INTERN ibool	srv_extra_undoslots = FALSE;
 
 UNIV_INTERN ibool	srv_fast_recovery = FALSE;
 
+UNIV_INTERN ibool	srv_use_purge_thread = FALSE;
+
 /* if TRUE, then we auto-extend the last data file */
 UNIV_INTERN ibool	srv_auto_extend_last_data_file	= FALSE;
 /* if != 0, this tells the max size auto-extending may increase the
@@ -381,6 +383,7 @@ this many index pages */
 UNIV_INTERN unsigned long long	srv_stats_sample_pages = 8;
 UNIV_INTERN ulint	srv_stats_method = 0;
 UNIV_INTERN ulint	srv_stats_auto_update = 1;
+UNIV_INTERN ulint	srv_stats_update_need_lock = 1;
 
 UNIV_INTERN ibool	srv_use_doublewrite_buf	= TRUE;
 UNIV_INTERN ibool	srv_use_checksums = TRUE;
@@ -2736,7 +2739,7 @@ srv_master_thread(
 					lsn_old = log_sys->lsn;
 					mutex_exit(&(log_sys->mutex));
 				} else if ((log_sys->lsn - oldest_lsn)
-					   > (log_sys->max_checkpoint_age)/2 ) {
+					   > (log_sys->max_checkpoint_age)/4 ) {
 
 					/* defence line (max_checkpoint_age * 1/2) */
 					ib_uint64_t	lsn = log_sys->lsn;
@@ -2772,7 +2775,7 @@ srv_master_thread(
 
 					if (!srv_use_doublewrite_buf) {
 						/* flush is faster than when doublewrite */
-						bpl = (bpl * 3) / 4;
+						bpl = (bpl * 7) / 8;
 					}
 
 					if (bpl) {
@@ -2856,6 +2859,7 @@ srv_master_thread(
 	/* Flush logs if needed */
 	srv_sync_log_buffer_in_background();
 
+	if (!srv_use_purge_thread) {
 	/* We run a full purge every 10 seconds, even if the server
 	were active */
 	do {
@@ -2872,6 +2876,7 @@ srv_master_thread(
 		srv_sync_log_buffer_in_background();
 
 	} while (n_pages_purged);
+	}
 
 	srv_main_thread_op_info = "flushing buffer pool pages";
 
@@ -2940,6 +2945,7 @@ srv_master_thread(
 		os_thread_sleep(100000);
 	}
 
+	if (!srv_use_purge_thread) {
 	srv_main_thread_op_info = "purging";
 
 	/* Run a full purge */
@@ -2956,6 +2962,7 @@ srv_master_thread(
 		srv_sync_log_buffer_in_background();
 
 	} while (n_pages_purged);
+	}
 
 	srv_main_thread_op_info = "reserving kernel mutex";
 
@@ -3108,3 +3115,67 @@ srv_master_thread(
 
 	OS_THREAD_DUMMY_RETURN;	/* Not reached, avoid compiler warning */
 }
+
+/*************************************************************************
+A thread which is devoted to purge, for take over the master thread's
+purging */
+UNIV_INTERN
+os_thread_ret_t
+srv_purge_thread(
+/*=============*/
+	void*	arg __attribute__((unused)))
+			/* in: a dummy parameter required by os_thread_create */
+{
+	ulint	n_pages_purged;
+	ulint	n_pages_purged_sum = 1; /* dummy */
+	ulint	history_len;
+	ulint	sleep_ms= 10000; /* initial: 10 sec. */
+
+#ifdef UNIV_DEBUG_THREAD_CREATION
+	fprintf(stderr, "Purge thread starts, id %lu\n",
+		os_thread_pf(os_thread_get_curr_id()));
+#endif
+
+	srv_table_reserve_slot(SRV_PURGE);
+	mutex_enter(&kernel_mutex);
+	srv_n_threads_active[SRV_PURGE]++;
+	mutex_exit(&kernel_mutex);
+
+loop:
+	if (srv_fast_shutdown && srv_shutdown_state > 0) {
+		goto exit_func;
+	}
+
+	os_thread_sleep( sleep_ms * 1000 );
+
+	history_len = trx_sys->rseg_history_len;
+	if (history_len > 1000)
+		sleep_ms /= 10;
+	if (sleep_ms < 10)
+		sleep_ms = 10;
+
+	n_pages_purged_sum = 0;
+
+	do {
+		if (srv_fast_shutdown && srv_shutdown_state > 0) {
+			goto exit_func;
+		}
+		n_pages_purged = trx_purge();
+		n_pages_purged_sum += n_pages_purged;
+	} while (n_pages_purged);
+
+	if (n_pages_purged_sum == 0)
+		sleep_ms *= 10;
+	if (sleep_ms > 10000)
+		sleep_ms = 10000;
+
+	goto loop;
+
+exit_func:
+	/* We count the number of threads in os_thread_exit(). A created
+	thread should always use that to exit and not use return() to exit. */
+
+	os_thread_exit(NULL);
+
+	OS_THREAD_DUMMY_RETURN;
+}

srv/srv0start.c

@@ -1544,6 +1544,12 @@ innobase_start_or_create_for_mysql(void)
 		dict_create();
 		srv_startup_is_before_trx_rollback_phase = FALSE;
 
+		if (trx_doublewrite == NULL) {
+			/* Create the doublewrite buffer here to avoid assertion error
+			   about page_no of doublewrite_buf */
+			trx_sys_create_doublewrite_buf();
+		}
+
 		if (srv_extra_rsegments)
 			trx_sys_create_extra_rseg(srv_extra_rsegments);
 #ifdef UNIV_LOG_ARCHIVE
@@ -1731,6 +1737,11 @@ innobase_start_or_create_for_mysql(void)
 
 	os_thread_create(&srv_master_thread, NULL, thread_ids
 			 + (1 + SRV_MAX_N_IO_THREADS));
+
+	if (srv_use_purge_thread) {
+		os_thread_create(&srv_purge_thread, NULL, thread_ids
+				 + (4 + SRV_MAX_N_IO_THREADS));
+	}
 #ifdef UNIV_DEBUG
 	/* buf_debug_prints = TRUE; */
 #endif /* UNIV_DEBUG */