srv0srv.c, log0log.c, srv0srv.h, ha_innodb.cc, ha_innodb.h:

  Implement innobase_very_fast_shutdown and innobase_start_trx_and_assign_read_view(); these were requested by Guilhem

innobase/include/srv0srv.h

@@ -100,7 +100,10 @@ extern ulint	srv_max_n_threads;
 extern lint	srv_conc_n_threads;
 
 extern ibool	srv_fast_shutdown;
-
+extern ibool	srv_very_fast_shutdown;  /* if this TRUE, do not flush the
+					 buffer pool to data files at the
+					 shutdown; we effectively 'crash'
+					 InnoDB */
 extern ibool	srv_innodb_status;
 
 extern ibool	srv_use_doublewrite_buf;

innobase/log/log0log.c

@@ -3048,13 +3048,25 @@ loop:
 #ifdef UNIV_LOG_ARCHIVE
 	log_archive_all();
 #endif /* UNIV_LOG_ARCHIVE */
+
+	if (!srv_very_fast_shutdown) {
+		/* In a 'very fast' shutdown we do not flush the buffer pool:
+		it is essentially a 'crash' of the InnoDB server. */
+
 		log_make_checkpoint_at(ut_dulint_max, TRUE);
+	} else {
+		/* Make sure that the log is all flushed to disk, so that
+		we can recover all committed transactions in a crash
+		recovery */
+		log_buffer_flush_to_disk();
+	}
 
 	mutex_enter(&(log_sys->mutex));
 
 	lsn = log_sys->lsn;
 
-	if (ut_dulint_cmp(lsn, log_sys->last_checkpoint_lsn) != 0
+	if ((ut_dulint_cmp(lsn, log_sys->last_checkpoint_lsn) != 0
+	    && !srv_very_fast_shutdown)
 #ifdef UNIV_LOG_ARCHIVE
 	   || (srv_log_archive_on
 	       && ut_dulint_cmp(lsn,
@@ -3098,11 +3110,12 @@ loop:
 	fil_flush_file_spaces(FIL_TABLESPACE);
 	fil_flush_file_spaces(FIL_LOG);
 
-	/* The next fil_write_... will pass the buffer pool: therefore
-	it is essential that the buffer pool has been completely flushed
-	to disk! */
+	/* The call fil_write_flushed_lsn_to_data_files() will pass the buffer
+	pool: therefore it is essential that the buffer pool has been
+	completely flushed to disk! (We do not call fil_write... if the
+	'very fast' shutdown is enabled.) */
 
-	if (!buf_all_freed()) {
+	if (!srv_very_fast_shutdown && !buf_all_freed()) {
 
 		goto loop;
 	}
@@ -3125,7 +3138,7 @@ loop:
 
 	/* Make some checks that the server really is quiet */
 	ut_a(srv_n_threads_active[SRV_MASTER] == 0);
-	ut_a(buf_all_freed());
+	ut_a(srv_very_fast_shutdown || buf_all_freed());
 	ut_a(0 == ut_dulint_cmp(lsn, log_sys->lsn));
 
 	if (ut_dulint_cmp(lsn, srv_start_lsn) < 0) {
@@ -3140,7 +3153,15 @@ loop:
 
 	srv_shutdown_lsn = lsn;
 
+	if (!srv_very_fast_shutdown) {
+		/* In a 'very fast' shutdown we do not flush the buffer pool:
+		it is essentially a 'crash' of the InnoDB server. Then we must
+		not write the lsn stamps to the data files, since at a
+		startup InnoDB deduces from the stamps if the previous
+		shutdown was clean. */
+
 		fil_write_flushed_lsn_to_data_files(lsn, arch_log_no);
+	}
 
 	fil_flush_file_spaces(FIL_TABLESPACE);
 
@@ -3148,7 +3169,7 @@ loop:
 
 	/* Make some checks that the server really is quiet */
 	ut_a(srv_n_threads_active[SRV_MASTER] == 0);
-	ut_a(buf_all_freed());
+	ut_a(srv_very_fast_shutdown || buf_all_freed());
 	ut_a(0 == ut_dulint_cmp(lsn, log_sys->lsn));
 }
 

innobase/srv/srv0srv.c

@@ -249,6 +249,10 @@ merge to completion before shutdown */
 
 ibool	srv_fast_shutdown	= FALSE;
 
+ibool	srv_very_fast_shutdown	= FALSE; /* if this TRUE, do not flush the
+					 buffer pool to data files at the
+					 shutdown; we effectively 'crash'
+					 InnoDB */
 /* Generate a innodb_status.<pid> file */
 ibool	srv_innodb_status	= FALSE;
 
@@ -2178,7 +2182,8 @@ loop:
 	/*****************************************************************/
 background_loop:
 	/* ---- In this loop we run background operations when the server
-	is quiet from user activity */
+	is quiet from user activity. Also in the case of a shutdown, we
+	loop here, flushing the buffer pool to the data files. */
 
 	/* The server has been quiet for a while: start running background
 	operations */
@@ -2251,7 +2256,16 @@ background_loop:
 	
 flush_loop:
 	srv_main_thread_op_info = "flushing buffer pool pages";
-	n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100, ut_dulint_max);
+
+	if (!srv_very_fast_shutdown) {
+		n_pages_flushed =
+			buf_flush_batch(BUF_FLUSH_LIST, 100, ut_dulint_max);
+	} else {
+		/* In a 'very fast' shutdown we do not flush the buffer pool
+		to data files: we set n_pages_flushed to 0 artificially. */
+
+		n_pages_flushed = 0;
+	}
 
 	srv_main_thread_op_info = "reserving kernel mutex";
 
@@ -2304,7 +2318,10 @@ flush_loop:
 
 			/* If we are doing a fast shutdown (= the default)
 			we do not do purge or insert buffer merge. But we
-			flush the buffer pool completely to disk. */
+			flush the buffer pool completely to disk.
+			In a 'very fast' shutdown we do not flush the buffer
+			pool to data files: we have set n_pages_flushed to
+			0 artificially. */
 
 			goto background_loop;
 		}

sql/ha_innodb.cc

@@ -20,6 +20,9 @@ NOTE: You can only use noninlined InnoDB functions in this file, because we
 have disables the InnoDB inlining in this file. */
 
 /* TODO list for the InnoDB handler in 4.1:
+  - Remove the flag innodb_active_trans from thd and replace it with a
+    function call innodb_active_trans(thd), which looks at the InnoDB
+    trx struct state field
   - Find out what kind of problems the OS X case-insensitivity causes to
     table and database names; should we 'normalize' the names like we do
     in Windows?
@@ -114,6 +117,9 @@ uint	innobase_flush_log_at_trx_commit	= 1;
 my_bool innobase_log_archive			= FALSE;/* unused */
 my_bool	innobase_use_native_aio			= FALSE;
 my_bool	innobase_fast_shutdown			= TRUE;
+my_bool innobase_very_fast_shutdown		= FALSE; /* this can be set to
+							 1 just prior calling
+							 innobase_end() */
 my_bool	innobase_file_per_table			= FALSE;
 my_bool innobase_locks_unsafe_for_binlog        = FALSE;
 my_bool innobase_create_status_file		= FALSE;
@@ -799,6 +805,10 @@ ha_innobase::init_table_handle_for_HANDLER(void)
 
         trx_assign_read_view(prebuilt->trx);
 
+	/* Set the MySQL flag to mark that there is an active transaction */
+
+	current_thd->transaction.all.innodb_active_trans = 1;
+
         /* We did the necessary inits in this function, no need to repeat them
         in row_search_for_mysql */
 
@@ -1059,6 +1069,15 @@ innobase_end(void)
 #endif
 	if (innodb_inited)
 	{
+	  if (innobase_very_fast_shutdown) {
+	    srv_very_fast_shutdown = TRUE;
+	    fprintf(stderr,
+"InnoDB: MySQL has requested a very fast shutdown without flushing\n"
+"InnoDB: the InnoDB buffer pool to data files. At the next mysqld startup\n"
+"InnoDB: InnoDB will do a crash recovery!\n");
+
+	  }
+
 	  innodb_inited= 0;
 	  if (innobase_shutdown_for_mysql() != DB_SUCCESS)
 	    err= 1;
@@ -1115,6 +1134,48 @@ innobase_commit_low(
 	trx_commit_for_mysql(trx);
 }
 
+/*********************************************************************
+Creates an InnoDB transaction struct for the thd if it does not yet have one.
+Starts a new InnoDB transaction if a transaction is not yet started. And
+assigns a new snapshot for a consistent read if the transaction does not yet
+have one. */
+
+int
+innobase_start_trx_and_assign_read_view(
+/*====================================*/
+			/* out: 0 */
+	THD*	thd)	/* in: MySQL thread handle of the user for whom
+			the transaction should be committed */
+{
+	trx_t*	trx;
+
+  	DBUG_ENTER("innobase_start_trx_and_assign_read_view");
+
+	/* Create a new trx struct for thd, if it does not yet have one */
+
+	trx = check_trx_exists(thd);
+
+	/* This is just to play safe: release a possible FIFO ticket and
+	search latch. Since we will reserve the kernel mutex, we have to
+	release the search system latch first to obey the latching order. */
+
+	innobase_release_stat_resources(trx);
+
+	/* If the transaction is not started yet, start it */
+
+	trx_start_if_not_started_noninline(trx);
+
+	/* Assign a read view if the transaction does not have it yet */
+
+	trx_assign_read_view(trx);
+
+	/* Set the MySQL flag to mark that there is an active transaction */
+
+	current_thd->transaction.all.innodb_active_trans = 1;
+
+	DBUG_RETURN(0);
+}
+
 /*********************************************************************
 Commits a transaction in an InnoDB database or marks an SQL statement
 ended. */
@@ -1146,8 +1207,10 @@ innobase_commit(
 
 	1. ::external_lock(),
 	2. ::start_stmt(),
-	3. innobase_query_caching_of_table_permitted(), and
+	3. innobase_query_caching_of_table_permitted(),
 	4. innobase_savepoint(),
+	5. ::init_table_handle_for_HANDLER(),
+	6. innobase_start_trx_and_assign_read_view()
 
 	and it is only set to 0 in a commit or a rollback. If it is 0 we know
 	there cannot be resources to be freed and we could return immediately.

sql/ha_innodb.h

@@ -191,6 +191,11 @@ extern my_bool innobase_log_archive,
                innobase_use_native_aio, innobase_fast_shutdown,
 	       innobase_file_per_table, innobase_locks_unsafe_for_binlog,
                innobase_create_status_file;
+extern my_bool innobase_very_fast_shutdown; /* set this to 1 just before
+					    calling innobase_end() if you want
+					    InnoDB to shut down without
+					    flushing the buffer pool: this
+					    is equivalent to a 'crash' */
 extern "C" {
 extern ulong srv_max_buf_pool_modified_pct;
 extern ulong srv_auto_extend_increment;
@@ -231,3 +236,4 @@ void innobase_release_temporary_latches(void* innobase_tid);
 
 void innobase_store_binlog_offset_and_flush_log(char *binlog_name,longlong offset);
 
+int innobase_start_trx_and_assign_read_view(THD* thd);