Merge 10.2 into 10.3

12 files changed, 268 insertions, 99 deletions

diff --git a/storage/innobase/buf/buf0dblwr.cc b/storage/innobase/buf/buf0dblwr.cc
index 6e5dee67714..3f998165ccc 100644
--- a/storage/innobase/buf/buf0dblwr.cc
+++ b/storage/innobase/buf/buf0dblwr.cc
@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1995, 2017, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2018, MariaDB Corporation.
+Copyright (c) 2013, 2019, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -264,6 +264,13 @@ too_small:
 
 		ut_ad(rw_lock_get_x_lock_count(&new_block->lock) == 1);
 		page_no = new_block->page.id.page_no();
+		/* We only do this in the debug build, to ensure that
+		both the check in buf_flush_init_for_writing() and
+		recv_parse_or_apply_log_rec_body() will see a valid
+		page type. The flushes of new_block are actually
+		unnecessary here.  */
+		ut_d(mlog_write_ulint(FIL_PAGE_TYPE + new_block->frame,
+				      FIL_PAGE_TYPE_SYS, MLOG_2BYTES, &mtr));
 
 		if (i == FSP_EXTENT_SIZE / 2) {
 			ut_a(page_no == FSP_EXTENT_SIZE);
@@ -326,6 +333,7 @@ too_small:
 
 	/* Flush the modified pages to disk and make a checkpoint */
 	log_make_checkpoint();
+	buf_dblwr_being_created = FALSE;
 
 	/* Remove doublewrite pages from LRU */
 	buf_pool_invalidate();
diff --git a/storage/innobase/buf/buf0flu.cc b/storage/innobase/buf/buf0flu.cc
index fffeafbdf8c..ae56fdae9ab 100644
--- a/storage/innobase/buf/buf0flu.cc
+++ b/storage/innobase/buf/buf0flu.cc
@@ -855,7 +855,9 @@ buf_flush_init_for_writing(
 	ut_ad(block == NULL || block->frame == page);
 	ut_ad(block == NULL || page_zip_ == NULL
 	      || &block->page.zip == page_zip_);
+	ut_ad(!block || newest_lsn);
 	ut_ad(page);
+	ut_ad(!newest_lsn || fil_page_get_type(page));
 
 	if (page_zip_) {
 		page_zip_des_t*	page_zip;
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index d254da182ff..6dc01f9297b 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -18573,6 +18573,33 @@ innodb_log_checksums_update(THD* thd, st_mysql_sys_var*, void* var_ptr,
 		thd, *static_cast<const my_bool*>(save));
 }
 
+#ifdef UNIV_DEBUG
+static
+void
+innobase_debug_sync_callback(srv_slot_t *slot, const void *value)
+{
+	const char *value_str = *static_cast<const char* const*>(value);
+	size_t len = strlen(value_str) + 1;
+
+
+	// One allocatoin for list node object and value.
+	void *buf = ut_malloc_nokey(sizeof(srv_slot_t::debug_sync_t) + len);
+	srv_slot_t::debug_sync_t *sync = new(buf) srv_slot_t::debug_sync_t();
+	strcpy(reinterpret_cast<char*>(&sync[1]), value_str);
+
+	rw_lock_x_lock(&slot->debug_sync_lock);
+	UT_LIST_ADD_LAST(slot->debug_sync, sync);
+	rw_lock_x_unlock(&slot->debug_sync_lock);
+}
+static
+void
+innobase_debug_sync_set(THD *thd, st_mysql_sys_var*, void *, const void *value)
+{
+	srv_for_each_thread(SRV_WORKER, innobase_debug_sync_callback, value);
+	srv_for_each_thread(SRV_PURGE, innobase_debug_sync_callback, value);
+}
+#endif
+
 static SHOW_VAR innodb_status_variables_export[]= {
 	{"Innodb", (char*) &show_innodb_vars, SHOW_FUNC},
 	{NullS, NullS, SHOW_LONG}
@@ -19025,7 +19052,8 @@ static MYSQL_SYSVAR_ULONG(purge_threads, srv_n_purge_threads,
   NULL, NULL,
   4,			/* Default setting */
   1,			/* Minimum value */
-  32, 0);		/* Maximum value */
+  srv_max_purge_threads,/* Maximum value */
+  0);
 
 static MYSQL_SYSVAR_ULONG(sync_array_size, srv_sync_array_size,
   PLUGIN_VAR_OPCMDARG | PLUGIN_VAR_READONLY,
@@ -20092,6 +20120,16 @@ static MYSQL_SYSVAR_BOOL(debug_force_scrubbing,
 			 0,
 			 "Perform extra scrubbing to increase test exposure",
 			 NULL, NULL, FALSE);
+
+char *innobase_debug_sync;
+static MYSQL_SYSVAR_STR(debug_sync, innobase_debug_sync,
+			PLUGIN_VAR_NOCMDARG,
+			"debug_sync for innodb purge threads. "
+			"Use it to set up sync points for all purge threads "
+			"at once. The commands will be applied sequentially at "
+			"the beginning of purging the next undo record.",
+			NULL,
+			innobase_debug_sync_set, NULL);
 #endif /* UNIV_DEBUG */
 
 static MYSQL_SYSVAR_BOOL(encrypt_temporary_tables, innodb_encrypt_temporary_tables,
@@ -20303,6 +20341,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(background_scrub_data_check_interval),
 #ifdef UNIV_DEBUG
   MYSQL_SYSVAR(debug_force_scrubbing),
+  MYSQL_SYSVAR(debug_sync),
 #endif
   MYSQL_SYSVAR(buf_dump_status_frequency),
   MYSQL_SYSVAR(background_thread),
diff --git a/storage/innobase/ibuf/ibuf0ibuf.cc b/storage/innobase/ibuf/ibuf0ibuf.cc
index 4dbd9f8ff1a..62aabe895b7 100644
--- a/storage/innobase/ibuf/ibuf0ibuf.cc
+++ b/storage/innobase/ibuf/ibuf0ibuf.cc
@@ -1987,14 +1987,14 @@ ibuf_add_free_page(void)
 	buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE_NEW);
 	page = buf_block_get_frame(block);
 
+	mlog_write_ulint(page + FIL_PAGE_TYPE, FIL_PAGE_IBUF_FREE_LIST,
+			 MLOG_2BYTES, &mtr);
+
 	/* Add the page to the free list and update the ibuf size data */
 
 	flst_add_last(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
 		      page + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST_NODE, &mtr);
 
-	mlog_write_ulint(page + FIL_PAGE_TYPE, FIL_PAGE_IBUF_FREE_LIST,
-			 MLOG_2BYTES, &mtr);
-
 	ibuf->seg_size++;
 	ibuf->free_list_len++;
 
diff --git a/storage/innobase/include/que0que.h b/storage/innobase/include/que0que.h
index b7d2aae2c1b..66dc00f5d10 100644
--- a/storage/innobase/include/que0que.h
+++ b/storage/innobase/include/que0que.h
@@ -378,6 +378,9 @@ struct que_thr_t{
 					related delete/updates */
 	row_prebuilt_t*	prebuilt;	/*!< prebuilt structure processed by
 					the query thread */
+
+	/** a slot of srv_sys.sys_threads, for DEBUG_SYNC in purge thread */
+	ut_d(srv_slot_t* thread_slot;)
 };
 
 #define QUE_THR_MAGIC_N		8476583
diff --git a/storage/innobase/include/srv0srv.h b/storage/innobase/include/srv0srv.h
index e35aa90331b..4644c1b8a0b 100644
--- a/storage/innobase/include/srv0srv.h
+++ b/storage/innobase/include/srv0srv.h
@@ -592,6 +592,8 @@ extern ulong	srv_fatal_semaphore_wait_threshold;
 /** Buffer pool dump status frequence in percentages */
 extern ulong srv_buf_dump_status_frequency;
 
+#define srv_max_purge_threads 32
+
 # ifdef UNIV_PFS_THREAD
 /* Keys to register InnoDB threads with performance schema */
 extern mysql_pfs_key_t	buf_dump_thread_key;
@@ -1105,8 +1107,23 @@ struct srv_slot_t{
 						to do */
 	que_thr_t*	thr;			/*!< suspended query thread
 						(only used for user threads) */
+#ifdef UNIV_DEBUG
+	struct debug_sync_t {
+		UT_LIST_NODE_T(debug_sync_t) debug_sync_list;
+	};
+	UT_LIST_BASE_NODE_T(debug_sync_t) debug_sync;
+	rw_lock_t debug_sync_lock;
+#endif
 };
 
+#ifdef UNIV_DEBUG
+typedef void srv_slot_callback_t(srv_slot_t*, const void*);
+
+void srv_for_each_thread(srv_thread_type type,
+			 srv_slot_callback_t callback,
+			 const void *arg);
+#endif
+
 #ifdef WITH_WSREP
 UNIV_INTERN
 void
diff --git a/storage/innobase/include/trx0purge.h b/storage/innobase/include/trx0purge.h
index 71e0b78a105..4bc5aded341 100644
--- a/storage/innobase/include/trx0purge.h
+++ b/storage/innobase/include/trx0purge.h
@@ -61,7 +61,12 @@ trx_purge(
 /*======*/
 	ulint	n_purge_threads,	/*!< in: number of purge tasks to
 					submit to task queue. */
-	bool	truncate);		/*!< in: truncate history if true */
+	bool	truncate		/*!< in: truncate history if true */
+#ifdef UNIV_DEBUG
+	, srv_slot_t *slot		/*!< in/out: purge coordinator
+					thread slot */
+#endif
+);
 
 /** Rollback segements from a given transaction with trx-no
 scheduled for purge. */
diff --git a/storage/innobase/row/row0purge.cc b/storage/innobase/row/row0purge.cc
index 89e336e1724..8c83482f53e 100644
--- a/storage/innobase/row/row0purge.cc
+++ b/storage/innobase/row/row0purge.cc
@@ -46,6 +46,7 @@ Created 3/14/1997 Heikki Tuuri
 #include "handler.h"
 #include "ha_innodb.h"
 #include "fil0fil.h"
+#include "debug_sync.h"
 
 /*************************************************************************
 IMPORTANT NOTE: Any operation that generates redo MUST check that there
@@ -1306,6 +1307,26 @@ row_purge_step(
 
 	node->start();
 
+#ifdef UNIV_DEBUG
+	srv_slot_t *slot = thr->thread_slot;
+	ut_ad(slot);
+
+	rw_lock_x_lock(&slot->debug_sync_lock);
+	while (UT_LIST_GET_LEN(slot->debug_sync)) {
+		srv_slot_t::debug_sync_t *sync =
+					UT_LIST_GET_FIRST(slot->debug_sync);
+		const char* sync_str = reinterpret_cast<char*>(&sync[1]);
+		bool result = debug_sync_set_action(current_thd,
+						    sync_str,
+						    strlen(sync_str));
+		ut_a(!result);
+
+		UT_LIST_REMOVE(slot->debug_sync, sync);
+		ut_free(sync);
+	}
+	rw_lock_x_unlock(&slot->debug_sync_lock);
+#endif
+
 	if (!(node->undo_recs == NULL || ib_vector_is_empty(node->undo_recs))) {
 		trx_purge_rec_t*purge_rec;
 
diff --git a/storage/innobase/row/row0vers.cc b/storage/innobase/row/row0vers.cc
index 04237b8f7a4..b662ce92f28 100644
--- a/storage/innobase/row/row0vers.cc
+++ b/storage/innobase/row/row0vers.cc
@@ -464,6 +464,7 @@ row_vers_build_clust_v_col(
 		vcol_info->set_used();
 		maria_table = vcol_info->table();
 	}
+	DEBUG_SYNC(current_thd, "ib_clust_v_col_before_row_allocated");
 
 	innobase_allocate_row_for_vcol(thd, index,
 				       &local_heap,
diff --git a/storage/innobase/srv/srv0srv.cc b/storage/innobase/srv/srv0srv.cc
index d130054b86a..556329e138e 100644
--- a/storage/innobase/srv/srv0srv.cc
+++ b/storage/innobase/srv/srv0srv.cc
@@ -594,7 +594,8 @@ struct srv_sys_t{
 	ulint		n_sys_threads;		/*!< size of the sys_threads
 						array */
 
-	srv_slot_t	sys_threads[32 + 1];	/*!< server thread table;
+	srv_slot_t
+	sys_threads[srv_max_purge_threads + 1];	/*!< server thread table;
 						os_event_set() and
 						os_event_reset() on
 						sys_threads[]->event are
@@ -642,11 +643,15 @@ and/or load it during startup. */
 char	srv_buffer_pool_dump_at_shutdown = TRUE;
 char	srv_buffer_pool_load_at_startup = TRUE;
 
+/** Slot index in the srv_sys.sys_threads array for the master thread. */
+#define SRV_MASTER_SLOT 0
+
 /** Slot index in the srv_sys.sys_threads array for the purge thread. */
-static const ulint	SRV_PURGE_SLOT	= 1;
+#define SRV_PURGE_SLOT 1
 
-/** Slot index in the srv_sys.sys_threads array for the master thread. */
-static const ulint	SRV_MASTER_SLOT = 0;
+/** Slot index in the srv_sys.sys_threads array from which purge workers start.
+  */
+#define SRV_WORKER_SLOTS_START 2
 
 #ifdef HAVE_PSI_STAGE_INTERFACE
 /** Performance schema stage event for monitoring ALTER TABLE progress
@@ -794,7 +799,7 @@ srv_reserve_slot(
 
 	case SRV_WORKER:
 		/* Find an empty slot, skip the master and purge slots. */
-		for (slot = &srv_sys.sys_threads[2];
+		for (slot = &srv_sys.sys_threads[SRV_WORKER_SLOTS_START];
 		     slot->in_use;
 		     ++slot) {
 
@@ -2458,8 +2463,9 @@ static bool srv_purge_should_exit()
 
 /*********************************************************************//**
 Fetch and execute a task from the work queue.
+@param [in,out]	slot	purge worker thread slot
 @return true if a task was executed */
-static bool srv_task_execute()
+static bool srv_task_execute(ut_d(srv_slot_t *slot))
 {
 	ut_ad(!srv_read_only_mode);
 	ut_ad(srv_force_recovery < SRV_FORCE_NO_BACKGROUND);
@@ -2470,6 +2476,7 @@ static bool srv_task_execute()
 		ut_a(que_node_get_type(thr->child) == QUE_NODE_PURGE);
 		UT_LIST_REMOVE(srv_sys.tasks, thr);
 		mutex_exit(&srv_sys.tasks_mutex);
+		ut_d(thr->thread_slot = slot);
 		que_run_threads(thr);
 		my_atomic_addlint(&purge_sys.n_completed, 1);
 		return true;
@@ -2506,6 +2513,13 @@ DECLARE_THREAD(srv_worker_thread)(
 
 	slot = srv_reserve_slot(SRV_WORKER);
 
+#ifdef UNIV_DEBUG
+	UT_LIST_INIT(slot->debug_sync,
+		     &srv_slot_t::debug_sync_t::debug_sync_list);
+	rw_lock_create(PFS_NOT_INSTRUMENTED, &slot->debug_sync_lock,
+		       SYNC_NO_ORDER_CHECK);
+#endif
+
 	ut_a(srv_n_purge_threads > 1);
 	ut_a(ulong(my_atomic_loadlint(&srv_sys.n_threads_active[SRV_WORKER]))
 	     < srv_n_purge_threads);
@@ -2518,7 +2532,7 @@ DECLARE_THREAD(srv_worker_thread)(
 		srv_suspend_thread(slot);
 		srv_resume_thread(slot);
 
-		if (srv_task_execute()) {
+		if (srv_task_execute(ut_d(slot))) {
 
 			/* If there are tasks in the queue, wakeup
 			the purge coordinator thread. */
@@ -2548,9 +2562,11 @@ DECLARE_THREAD(srv_worker_thread)(
 /** Do the actual purge operation.
 @param[in,out]	n_total_purged	total number of purged pages
 @return length of history list before the last purge batch. */
-static
-ulint
-srv_do_purge(ulint* n_total_purged)
+static ulint srv_do_purge(ulint* n_total_purged
+#ifdef UNIV_DEBUG
+			  , srv_slot_t* slot /*!< purge coordinator */
+#endif
+			  )
 {
 	ulint		n_pages_purged;
 
@@ -2616,7 +2632,11 @@ srv_do_purge(ulint* n_total_purged)
 
 		n_pages_purged = trx_purge(
 			n_use_threads,
-			(++count % rseg_truncate_frequency) == 0);
+			(++count % rseg_truncate_frequency) == 0
+#ifdef UNIV_DEBUG
+			, slot
+#endif
+					   );
 
 		*n_total_purged += n_pages_purged;
 	} while (n_pages_purged > 0 && !purge_sys.paused()
@@ -2624,6 +2644,9 @@ srv_do_purge(ulint* n_total_purged)
 
 	return(rseg_history_len);
 }
+#ifndef UNIV_DEBUG
+# define srv_do_purge(n_total_purged, slot) srv_do_purge(n_total_purged)
+#endif
 
 /*********************************************************************//**
 Suspend the purge coordinator thread. */
@@ -2718,6 +2741,12 @@ DECLARE_THREAD(srv_purge_coordinator_thread)(
 
 	slot = srv_reserve_slot(SRV_PURGE);
 
+#ifdef UNIV_DEBUG
+	UT_LIST_INIT(slot->debug_sync,
+		     &srv_slot_t::debug_sync_t::debug_sync_list);
+	rw_lock_create(PFS_NOT_INSTRUMENTED, &slot->debug_sync_lock,
+		       SYNC_NO_ORDER_CHECK);
+#endif
 	ulint	rseg_history_len = trx_sys.history_size();
 
 	do {
@@ -2739,7 +2768,7 @@ DECLARE_THREAD(srv_purge_coordinator_thread)(
 
 		n_total_purged = 0;
 
-		rseg_history_len = srv_do_purge(&n_total_purged);
+		rseg_history_len = srv_do_purge(&n_total_purged, slot);
 	} while (!srv_purge_should_exit());
 
 	/* The task queue should always be empty, independent of fast
@@ -2897,3 +2926,33 @@ srv_was_tablespace_truncated(const fil_space_t* space)
 	return (!is_system_tablespace(space->id)
 		&& truncate_t::was_tablespace_truncated(space->id));
 }
+
+#ifdef UNIV_DEBUG
+static ulint get_first_slot(srv_thread_type type)
+{
+	switch (type) {
+	case SRV_MASTER:
+		return SRV_MASTER_SLOT;
+	case SRV_PURGE:
+		return SRV_PURGE_SLOT;
+	case SRV_WORKER:
+		/* Find an empty slot, skip the master and purge slots. */
+		return SRV_WORKER_SLOTS_START;
+	default:
+		ut_error;
+	}
+}
+
+void srv_for_each_thread(srv_thread_type type,
+			 srv_slot_callback_t callback,
+			 const void *arg)
+{
+	for (ulint slot_idx= get_first_slot(type);
+	     slot_idx < srv_sys.n_sys_threads
+		     && srv_sys.sys_threads[slot_idx].in_use
+		     && srv_sys.sys_threads[slot_idx].type == type;
+	     slot_idx++) {
+		callback(&srv_sys.sys_threads[slot_idx], arg);
+	}
+}
+#endif
diff --git a/storage/innobase/trx/trx0purge.cc b/storage/innobase/trx/trx0purge.cc
index 475babb6195..3ae8db63121 100644
--- a/storage/innobase/trx/trx0purge.cc
+++ b/storage/innobase/trx/trx0purge.cc
@@ -1561,7 +1561,12 @@ trx_purge(
 /*======*/
 	ulint	n_purge_threads,	/*!< in: number of purge tasks
 					to submit to the work queue */
-	bool	truncate)		/*!< in: truncate history if true */
+	bool	truncate		/*!< in: truncate history if true */
+#ifdef UNIV_DEBUG
+	, srv_slot_t *slot		/*!< in/out: purge coordinator
+					thread slot */
+#endif
+)
 {
 	que_thr_t*	thr = NULL;
 	ulint		n_pages_handled;
@@ -1597,6 +1602,7 @@ trx_purge(
 
 	thr = que_fork_scheduler_round_robin(purge_sys.query, thr);
 
+	ut_d(thr->thread_slot = slot);
 	que_run_threads(thr);
 
 	my_atomic_addlint(&purge_sys.n_completed, 1);
diff --git a/storage/tokudb/mysql-test/tokudb_parts/r/partition_debug_tokudb.result b/storage/tokudb/mysql-test/tokudb_parts/r/partition_debug_tokudb.result
index 125155bad9f..ae95fc691a4 100644
--- a/storage/tokudb/mysql-test/tokudb_parts/r/partition_debug_tokudb.result
+++ b/storage/tokudb/mysql-test/tokudb_parts/r/partition_debug_tokudb.result
@@ -12,6 +12,7 @@ call mtr.add_suppression("TokuDB: Warning: MySQL is trying to drop table ");
 call mtr.add_suppression("Attempting backtrace. You can use the following information to find out");
 flush tables;
 # Crash testing ADD PARTITION
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -73,7 +74,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -137,7 +138,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -201,7 +202,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -265,7 +266,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -329,7 +330,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -393,7 +394,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -457,7 +458,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -522,7 +523,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -585,7 +586,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_add_partition_10";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -648,8 +649,9 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_add_partition_10";
+SET SESSION debug_dbug=@save_dbug;
 # Error recovery testing ADD PARTITION
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -766,7 +768,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -883,7 +885,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1000,7 +1002,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1117,7 +1119,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1234,7 +1236,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1351,7 +1353,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1468,7 +1470,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1587,7 +1589,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1706,7 +1708,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_add_partition_10";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1825,8 +1827,9 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_add_partition_10";
+SET SESSION debug_dbug=@save_dbug;
 # Test DROP PARTITION
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1887,7 +1890,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -1950,7 +1953,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2013,7 +2016,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2071,7 +2074,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2129,7 +2132,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2187,7 +2190,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2243,7 +2246,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2299,7 +2302,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_drop_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2355,8 +2358,9 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_drop_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 # Error recovery DROP PARTITION
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2471,7 +2475,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2586,7 +2590,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2701,7 +2705,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2806,7 +2810,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -2911,7 +2915,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3016,7 +3020,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3121,7 +3125,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3226,7 +3230,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_drop_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3331,9 +3335,10 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_drop_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 # Test change partition (REORGANIZE/REBUILD/COALESCE
 # or ADD HASH PARTITION).
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3396,7 +3401,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3461,7 +3466,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3526,7 +3531,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3591,7 +3596,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3656,7 +3661,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3721,7 +3726,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3787,7 +3792,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3853,7 +3858,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3917,7 +3922,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_10";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -3981,7 +3986,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_10";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_11";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4045,7 +4050,7 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_11";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,crash_change_partition_12";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4109,9 +4114,10 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,crash_change_partition_12";
+SET SESSION debug_dbug=@save_dbug;
 # Error recovery change partition (REORGANIZE/REBUILD/COALESCE
 # or ADD HASH PARTITION).
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_1";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4230,7 +4236,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_2";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4349,7 +4355,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_3";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4468,7 +4474,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_4";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4587,7 +4593,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_5";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4706,7 +4712,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_6";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4825,7 +4831,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_7";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -4946,7 +4952,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_8";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -5067,7 +5073,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_9";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -5188,7 +5194,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_9";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_10";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -5309,7 +5315,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_10";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_11";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -5430,7 +5436,7 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_11";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,fail_change_partition_12";
 CREATE TABLE t1 (a INT, b VARCHAR(64))
 ENGINE = 'TokuDB'
@@ -5551,13 +5557,14 @@ a	b
 4	Original from partition p0
 UNLOCK TABLES;
 DROP TABLE t1;
-SET SESSION debug_dbug="-d,fail_change_partition_12";
+SET SESSION debug_dbug=@save_dbug;
 #
 # WL#4445: EXCHANGE PARTITION WITH TABLE
 # Verify ddl_log and TokuDB in case of crashing.
 call mtr.add_suppression("TokuDB: Warning: allocated tablespace .*, old maximum was ");
 call mtr.add_suppression("Attempting backtrace. You can use the following information to find out");
 call mtr.add_suppression("table .* does not exist in the TokuDB internal");
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_1";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -5656,7 +5663,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_2";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -5755,7 +5762,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_3";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -5854,7 +5861,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_4";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -5953,7 +5960,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_5";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6052,7 +6059,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_6";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6151,7 +6158,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_7";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6250,7 +6257,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_8";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6349,7 +6356,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_abort_9";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6448,7 +6455,8 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_abort_9";
+SET SESSION debug_dbug=@save_dbug;
+SET @save_dbug=@@debug_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_1";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6542,7 +6550,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_1";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_2";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6636,7 +6644,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_2";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_3";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6730,7 +6738,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_3";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_4";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6824,7 +6832,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_4";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_5";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -6918,7 +6926,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_5";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_6";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -7012,7 +7020,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_6";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_7";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -7106,7 +7114,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_7";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_8";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -7200,7 +7208,7 @@ a	b
 7	Original from table t2
 8	Original from table t2
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_8";
+SET SESSION debug_dbug=@save_dbug;
 SET SESSION debug_dbug="+d,exchange_partition_fail_9";
 CREATE TABLE t2 (a INT, b VARCHAR(64)) ENGINE = TokuDB;
 INSERT INTO t2 VALUES (5, "Original from table t2"), (6, "Original from table t2"), (7, "Original from table t2"), (8, "Original from table t2");
@@ -7294,4 +7302,4 @@ a	b
 3	Original from partition p0
 4	Original from partition p0
 DROP TABLE t2;
-SET SESSION debug_dbug="-d,exchange_partition_fail_9";
+SET SESSION debug_dbug=@save_dbug;