srv0srv.c 49.6 KB
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/******************************************************
The database server main program

NOTE: SQL Server 7 uses something which the documentation
calls user mode scheduled threads (UMS threads). One such
thread is usually allocated per processor. Win32
documentation does not know any UMS threads, which suggests
that the concept is internal to SQL Server 7. It may mean that
SQL Server 7 does all the scheduling of threads itself, even
in i/o waits. We should maybe modify Innobase to use the same
technique, because thread switches within NT may be too slow.

SQL Server 7 also mentions fibers, which are cooperatively
scheduled threads. They can boost performance by 5 %,
according to the Delaney and Soukup's book.

Windows 2000 will have something called thread pooling
(see msdn website), which we could possibly use.

Another possibility could be to use some very fast user space
thread library. This might confuse NT though.

(c) 1995 Innobase Oy

Created 10/8/1995 Heikki Tuuri
*******************************************************/

#include "srv0srv.h"

#include "ut0mem.h"
#include "os0proc.h"
#include "mem0mem.h"
#include "sync0sync.h"
#include "sync0ipm.h"
#include "thr0loc.h"
#include "com0com.h"
#include "com0shm.h"
#include "que0que.h"
#include "srv0que.h"
#include "log0recv.h"
#include "odbc0odbc.h"
#include "pars0pars.h"
#include "usr0sess.h"
#include "lock0lock.h"
#include "trx0purge.h"
#include "ibuf0ibuf.h"
#include "buf0flu.h"
#include "btr0sea.h"

/* The following counter is incremented whenever there is some user activity
in the server */
ulint	srv_activity_count	= 0;

/* Server parameters which are read from the initfile */

/* The following three are dir paths which are catenated before file
names, where the file name itself may also contain a path */

char*	srv_data_home 	= NULL;
char*	srv_logs_home 	= NULL;
char*	srv_arch_dir 	= NULL;

ulint	srv_n_data_files = 0;
char**	srv_data_file_names = NULL;
ulint*	srv_data_file_sizes = NULL;	/* size in database pages */ 

char**	srv_log_group_home_dirs = NULL; 

ulint	srv_n_log_groups	= ULINT_MAX;
ulint	srv_n_log_files		= ULINT_MAX;
ulint	srv_log_file_size	= ULINT_MAX;	/* size in database pages */ 
ibool	srv_log_archive_on	= TRUE;
ulint	srv_log_buffer_size	= ULINT_MAX;	/* size in database pages */ 
ibool	srv_flush_log_at_trx_commit = TRUE;

ibool	srv_use_native_aio	= FALSE;
		
ulint	srv_pool_size		= ULINT_MAX;	/* size in database pages;
						MySQL originally sets this
						value in megabytes */ 
ulint	srv_mem_pool_size	= ULINT_MAX;	/* size in bytes */ 
ulint	srv_lock_table_size	= ULINT_MAX;

ulint	srv_n_file_io_threads	= ULINT_MAX;

ibool	srv_archive_recovery	= 0;
dulint	srv_archive_recovery_limit_lsn;

ulint	srv_lock_wait_timeout	= 1024 * 1024 * 1024;
/*-------------------------------------------*/
ulint	srv_n_spin_wait_rounds	= 20;
ulint	srv_spin_wait_delay	= 5;
ibool	srv_priority_boost	= TRUE;
char	srv_endpoint_name[COM_MAX_ADDR_LEN];
ulint	srv_n_com_threads	= ULINT_MAX;
ulint	srv_n_worker_threads	= ULINT_MAX;

ibool	srv_print_thread_releases	= FALSE;
ibool	srv_print_lock_waits		= FALSE;
ibool	srv_print_buf_io		= FALSE;
ibool	srv_print_log_io		= FALSE;
ibool	srv_print_latch_waits		= FALSE;

/* The parameters below are obsolete: */

ibool	srv_print_parsed_sql		= FALSE;

ulint	srv_sim_disk_wait_pct		= ULINT_MAX;
ulint	srv_sim_disk_wait_len		= ULINT_MAX;
ibool	srv_sim_disk_wait_by_yield	= FALSE;
ibool	srv_sim_disk_wait_by_wait	= FALSE;

ibool	srv_measure_contention	= FALSE;
ibool	srv_measure_by_spin	= FALSE;
	
ibool	srv_test_extra_mutexes	= FALSE;
ibool	srv_test_nocache	= FALSE;
ibool	srv_test_cache_evict	= FALSE;

ibool	srv_test_sync		= FALSE;
ulint	srv_test_n_threads	= ULINT_MAX;
ulint	srv_test_n_loops	= ULINT_MAX;
ulint	srv_test_n_free_rnds	= ULINT_MAX;
ulint	srv_test_n_reserved_rnds = ULINT_MAX;
ulint	srv_test_array_size	= ULINT_MAX;
ulint	srv_test_n_mutexes	= ULINT_MAX;

/*
	IMPLEMENTATION OF THE SERVER MAIN PROGRAM
	=========================================

There is the following analogue between this database
server and an operating system kernel:

DB concept			equivalent OS concept
----------			---------------------
transaction		--	process;

query thread		--	thread;

lock			--	semaphore;

transaction set to
the rollback state	--	kill signal delivered to a process;

kernel			--	kernel;

query thread execution:
(a) without kernel mutex
reserved	 	-- 	process executing in user mode;
(b) with kernel mutex reserved
			--	process executing in kernel mode;

The server is controlled by a master thread which runs at
a priority higher than normal, that is, higher than user threads.
It sleeps most of the time, and wakes up, say, every 300 milliseconds,
to check whether there is anything happening in the server which
requires intervention of the master thread. Such situations may be,
for example, when flushing of dirty blocks is needed in the buffer
pool or old version of database rows have to be cleaned away.

The threads which we call user threads serve the queries of
the clients and input from the console of the server.
They run at normal priority. The server may have several
communications endpoints. A dedicated set of user threads waits
at each of these endpoints ready to receive a client request.
Each request is taken by a single user thread, which then starts
processing and, when the result is ready, sends it to the client
and returns to wait at the same endpoint the thread started from.

So, we do not have dedicated communication threads listening at
the endpoints and dealing the jobs to dedicated worker threads.
Our architecture saves one thread swithch per request, compared
to the solution with dedicated communication threads
which amounts to 15 microseconds on 100 MHz Pentium
running NT. If the client
is communicating over a network, this saving is negligible, but
if the client resides in the same machine, maybe in an SMP machine
on a different processor from the server thread, the saving
can be important as the threads can communicate over shared
memory with an overhead of a few microseconds.

We may later implement a dedicated communication thread solution
for those endpoints which communicate over a network.

Our solution with user threads has two problems: for each endpoint
there has to be a number of listening threads. If there are many
communication endpoints, it may be difficult to set the right number
of concurrent threads in the system, as many of the threads
may always be waiting at less busy endpoints. Another problem
is queuing of the messages, as the server internally does not
offer any queue for jobs.

Another group of user threads is intended for splitting the
queries and processing them in parallel. Let us call these
parallel communication threads. These threads are waiting for
parallelized tasks, suspended on event semaphores.

A single user thread waits for input from the console,
like a command to shut the database.

Utility threads are a different group of threads which takes
care of the buffer pool flushing and other, mainly background
operations, in the server.
Some of these utility threads always run at a lower than normal
priority, so that they are always in background. Some of them
may dynamically boost their priority by the pri_adjust function,
even to higher than normal priority, if their task becomes urgent.
The running of utilities is controlled by high- and low-water marks
of urgency. The urgency may be measured by the number of dirty blocks
in the buffer pool, in the case of the flush thread, for example.
When the high-water mark is exceeded, an utility starts running, until
the urgency drops under the low-water mark. Then the utility thread
suspend itself to wait for an event. The master thread is
responsible of signaling this event when the utility thread is
again needed.

For each individual type of utility, some threads always remain
at lower than normal priority. This is because pri_adjust is implemented
so that the threads at normal or higher priority control their
share of running time by calling sleep. Thus, if the load of the
system sudenly drops, these threads cannot necessarily utilize
the system fully. The background priority threads make up for this,
starting to run when the load drops.

When there is no activity in the system, also the master thread
suspends itself to wait for an event making
the server totally silent. The responsibility to signal this
event is on the user thread which again receives a message
from a client.

There is still one complication in our server design. If a
background utility thread obtains a resource (e.g., mutex) needed by a user
thread, and there is also some other user activity in the system,
the user thread may have to wait indefinitely long for the
resource, as the OS does not schedule a background thread if
there is some other runnable user thread. This problem is called
priority inversion in real-time programming.

One solution to the priority inversion problem would be to
keep record of which thread owns which resource and
in the above case boost the priority of the background thread
so that it will be scheduled and it can release the resource.
This solution is called priority inheritance in real-time programming.
A drawback of this solution is that the overhead of acquiring a mutex 
increases slightly, maybe 0.2 microseconds on a 100 MHz Pentium, because
the thread has to call os_thread_get_curr_id.
This may be compared to 0.5 microsecond overhead for a mutex lock-unlock
pair. Note that the thread
cannot store the information in the resource, say mutex, itself,
because competing threads could wipe out the information if it is
stored before acquiring the mutex, and if it stored afterwards,
the information is outdated for the time of one machine instruction,
at least. (To be precise, the information could be stored to
lock_word in mutex if the machine supports atomic swap.)

The above solution with priority inheritance may become actual in the
future, but at the moment we plan to implement a more coarse solution,
which could be called a global priority inheritance. If a thread
has to wait for a long time, say 300 milliseconds, for a resource,
we just guess that it may be waiting for a resource owned by a background
thread, and boost the the priority of all runnable background threads
to the normal level. The background threads then themselves adjust
their fixed priority back to background after releasing all resources
they had (or, at some fixed points in their program code).

What is the performance of the global priority inheritance solution?
We may weigh the length of the wait time 300 milliseconds, during
which the system processes some other thread
to the cost of boosting the priority of each runnable background
thread, rescheduling it, and lowering the priority again.
On 100 MHz Pentium + NT this overhead may be of the order 100
microseconds per thread. So, if the number of runnable background
threads is not very big, say < 100, the cost is tolerable.
Utility threads probably will access resources used by
user threads not very often, so collisions of user threads
to preempted utility threads should not happen very often.

The thread table contains
information of the current status of each thread existing in the system,
and also the event semaphores used in suspending the master thread
and utility and parallel communication threads when they have nothing to do.
The thread table can be seen as an analogue to the process table
in a traditional Unix implementation.

The thread table is also used in the global priority inheritance
scheme. This brings in one additional complication: threads accessing
the thread table must have at least normal fixed priority,
because the priority inheritance solution does not work if a background
thread is preempted while possessing the mutex protecting the thread table.
So, if a thread accesses the thread table, its priority has to be
boosted at least to normal. This priority requirement can be seen similar to
the privileged mode used when processing the kernel calls in traditional
Unix.*/

/* Thread slot in the thread table */
struct srv_slot_struct{
	os_thread_id_t	id;		/* thread id */
	os_thread_t	handle;		/* thread handle */
	ulint		type;		/* thread type: user, utility etc. */
	ibool		in_use;		/* TRUE if this slot is in use */
	ibool		suspended;	/* TRUE if the thread is waiting
					for the event of this slot */
	ib_time_t	suspend_time;	/* time when the thread was
					suspended */
	os_event_t	event;		/* event used in suspending the
					thread when it has nothing to do */
	que_thr_t*	thr;		/* suspended query thread (only
					used for MySQL threads) */
};

/* Table for MySQL threads where they will be suspended to wait for locks */
srv_slot_t*	srv_mysql_table = NULL;

os_event_t	srv_lock_timeout_thread_event;

srv_sys_t*	srv_sys	= NULL;

byte		srv_pad1[64];	/* padding to prevent other memory update
				hotspots from residing on the same memory
				cache line */
mutex_t*	kernel_mutex_temp;/* mutex protecting the server, trx structs,
				query threads, and lock table */
byte		srv_pad2[64];	/* padding to prevent other memory update
				hotspots from residing on the same memory
				cache line */

/* The following three values measure the urgency of the jobs of
buffer, version, and insert threads. They may vary from 0 - 1000.
The server mutex protects all these variables. The low-water values
tell that the server can acquiesce the utility when the value
drops below this low-water mark. */

ulint	srv_meter[SRV_MASTER + 1];
ulint	srv_meter_low_water[SRV_MASTER + 1];
ulint	srv_meter_high_water[SRV_MASTER + 1];
ulint	srv_meter_high_water2[SRV_MASTER + 1];
ulint	srv_meter_foreground[SRV_MASTER + 1];

/* The following values give info about the activity going on in
the database. They are protected by the server mutex. The arrays
are indexed by the type of the thread. */

ulint	srv_n_threads_active[SRV_MASTER + 1];
ulint	srv_n_threads[SRV_MASTER + 1];


/*************************************************************************
Accessor function to get pointer to n'th slot in the server thread
table. */
static
srv_slot_t*
srv_table_get_nth_slot(
/*===================*/
				/* out: pointer to the slot */
	ulint	index)		/* in: index of the slot */
{
	ut_a(index < OS_THREAD_MAX_N);

	return(srv_sys->threads + index);
}

/*************************************************************************
Gets the number of threads in the system. */

ulint
srv_get_n_threads(void)
/*===================*/
{
	ulint	i;
	ulint	n_threads	= 0;

	mutex_enter(&kernel_mutex);

	for (i = SRV_COM; i < SRV_MASTER + 1; i++) {
	
		n_threads += srv_n_threads[i];
	}

	mutex_exit(&kernel_mutex);

	return(n_threads);
}

/*************************************************************************
Reserves a slot in the thread table for the current thread. Also creates the
thread local storage struct for the current thread. NOTE! The server mutex
has to be reserved by the caller! */
static
ulint
srv_table_reserve_slot(
/*===================*/
			/* out: reserved slot index */
	ulint	type)	/* in: type of the thread: one of SRV_COM, ... */
{
	srv_slot_t*	slot;
	ulint		i;
	
	ut_a(type > 0);
	ut_a(type <= SRV_MASTER);

	i = 0;
	slot = srv_table_get_nth_slot(i);

	while (slot->in_use) {
		i++;
		slot = srv_table_get_nth_slot(i);
	}

	ut_a(slot->in_use == FALSE);
	
	slot->in_use = TRUE;
	slot->suspended = FALSE;
	slot->id = os_thread_get_curr_id();
	slot->handle = os_thread_get_curr();
	slot->type = type;

	thr_local_create();

	thr_local_set_slot_no(os_thread_get_curr_id(), i);

	return(i);
}

/*************************************************************************
Suspends the calling thread to wait for the event in its thread slot.
NOTE! The server mutex has to be reserved by the caller! */
static
os_event_t
srv_suspend_thread(void)
/*====================*/
			/* out: event for the calling thread to wait */
{
	srv_slot_t*	slot;
	os_event_t	event;
	ulint		slot_no;
	ulint		type;

	ut_ad(mutex_own(&kernel_mutex));
	
	slot_no = thr_local_get_slot_no(os_thread_get_curr_id());

	if (srv_print_thread_releases) {
	
		printf("Suspending thread %lu to slot %lu meter %lu\n",
		os_thread_get_curr_id(), slot_no, srv_meter[SRV_RECOVERY]);
	}

	slot = srv_table_get_nth_slot(slot_no);

	type = slot->type;

	ut_ad(type >= SRV_WORKER);
	ut_ad(type <= SRV_MASTER);

	event = slot->event;
	
	slot->suspended = TRUE;

	ut_ad(srv_n_threads_active[type] > 0);

	srv_n_threads_active[type]--;

	os_event_reset(event);

	return(event);
}

/*************************************************************************
Releases threads of the type given from suspension in the thread table.
NOTE! The server mutex has to be reserved by the caller! */

ulint
srv_release_threads(
/*================*/
			/* out: number of threads released: this may be
			< n if not enough threads were suspended at the
			moment */
	ulint	type,	/* in: thread type */
	ulint	n)	/* in: number of threads to release */
{
	srv_slot_t*	slot;
	ulint		i;
	ulint		count	= 0;

	ut_ad(type >= SRV_WORKER);
	ut_ad(type <= SRV_MASTER);
	ut_ad(n > 0);
	ut_ad(mutex_own(&kernel_mutex));
	
	for (i = 0; i < OS_THREAD_MAX_N; i++) {
	
		slot = srv_table_get_nth_slot(i);

		if ((slot->type == type) && slot->suspended) {
			
			slot->suspended = FALSE;

			srv_n_threads_active[type]++;

			os_event_set(slot->event);

			if (srv_print_thread_releases) {
				printf(
		"Releasing thread %lu type %lu from slot %lu meter %lu\n",
				slot->id, type, i, srv_meter[SRV_RECOVERY]);
			}

			count++;

			if (count == n) {
				break;
			}
		}
	}

	return(count);
}

/*************************************************************************
Returns the calling thread type. */

ulint
srv_get_thread_type(void)
/*=====================*/
			/* out: SRV_COM, ... */
{
	ulint		slot_no;
	srv_slot_t*	slot;
	ulint		type;

	mutex_enter(&kernel_mutex);
	
	slot_no = thr_local_get_slot_no(os_thread_get_curr_id());

	slot = srv_table_get_nth_slot(slot_no);

	type = slot->type;

	ut_ad(type >= SRV_WORKER);
	ut_ad(type <= SRV_MASTER);

	mutex_exit(&kernel_mutex);

	return(type);
}

/***********************************************************************
Increments by 1 the count of active threads of the type given
and releases master thread if necessary. */
static
void
srv_inc_thread_count(
/*=================*/
	ulint	type)	/* in: type of the thread */
{
	mutex_enter(&kernel_mutex);

	srv_activity_count++;
	
	srv_n_threads_active[type]++;
		
	if (srv_n_threads_active[SRV_MASTER] == 0) {

		srv_release_threads(SRV_MASTER, 1);
	}

	mutex_exit(&kernel_mutex);
}

/***********************************************************************
Decrements by 1 the count of active threads of the type given. */
static
void
srv_dec_thread_count(
/*=================*/
	ulint	type)	/* in: type of the thread */

{
	mutex_enter(&kernel_mutex);

	/* FIXME: the following assertion sometimes fails: */

	if (srv_n_threads_active[type] == 0) {
		printf("Error: thread type %lu\n", type);

		ut_ad(0);
	}	

	srv_n_threads_active[type]--;

	mutex_exit(&kernel_mutex);
}

/***********************************************************************
Calculates the number of allowed utility threads for a thread to decide if
it has to suspend itself in the thread table. */
static
ulint
srv_max_n_utilities(
/*================*/
			/* out: maximum number of allowed utilities
			of the type given */
	ulint	type)	/* in: utility type */
{
	ulint	ret;

	if (srv_n_threads_active[SRV_COM] == 0) {
		if (srv_meter[type] > srv_meter_low_water[type]) {
			return(srv_n_threads[type] / 2);
		} else {
			return(0);
		}
	} else {

		if (srv_meter[type] < srv_meter_foreground[type]) {
			return(0);
		}
		ret = 1 + ((srv_n_threads[type]
		     * (ulint)(srv_meter[type] - srv_meter_foreground[type]))
		     / (ulint)(1000 - srv_meter_foreground[type]));
		if (ret > srv_n_threads[type]) {
			return(srv_n_threads[type]);
		} else {
			return(ret);
		}
	}
}

/***********************************************************************
Increments the utility meter by the value given and releases utility
threads if necessary. */

void
srv_increment_meter(
/*================*/
	ulint	type,	/* in: utility type */
	ulint	n)	/* in: value to add to meter */
{
	ulint	m;

	mutex_enter(&kernel_mutex);

	srv_meter[type] += n;

	m = srv_max_n_utilities(type);

	if (m > srv_n_threads_active[type]) {
		
		srv_release_threads(type, m - srv_n_threads_active[type]);
	}

	mutex_exit(&kernel_mutex);
}

/***********************************************************************
Releases max number of utility threads if no queries are active and
the high-water mark for the utility is exceeded. */

void
srv_release_max_if_no_queries(void)
/*===============================*/
{
	ulint	m;
	ulint	type;

	mutex_enter(&kernel_mutex);

	if (srv_n_threads_active[SRV_COM] > 0) {
		mutex_exit(&kernel_mutex);

		return;
	}

	type = SRV_RECOVERY;
	
	m = srv_n_threads[type] / 2;

	if ((srv_meter[type] > srv_meter_high_water[type])
				&& (srv_n_threads_active[type] < m)) {

		srv_release_threads(type, m - srv_n_threads_active[type]);

		printf("Releasing max background\n");
	}

	mutex_exit(&kernel_mutex);
}

/***********************************************************************
Releases one utility thread if no queries are active and
the high-water mark 2 for the utility is exceeded. */
static
void
srv_release_one_if_no_queries(void)
/*===============================*/
{
	ulint	m;
	ulint	type;

	mutex_enter(&kernel_mutex);

	if (srv_n_threads_active[SRV_COM] > 0) {
		mutex_exit(&kernel_mutex);

		return;
	}

	type = SRV_RECOVERY;
	
	m = 1;

	if ((srv_meter[type] > srv_meter_high_water2[type])
	   				&& (srv_n_threads_active[type] < m)) {

		srv_release_threads(type, m - srv_n_threads_active[type]);

		printf("Releasing one background\n");
	}

	mutex_exit(&kernel_mutex);
}

#ifdef notdefined
/***********************************************************************
Decrements the utility meter by the value given and suspends the calling
thread, which must be an utility thread of the type given, if necessary. */
static
void
srv_decrement_meter(
/*================*/
	ulint	type,	/* in: utility type */
	ulint	n)	/* in: value to subtract from meter */
{
	ulint		opt;
	os_event_t	event;
	
	mutex_enter(&kernel_mutex);

	if (srv_meter[type] < n) {
		srv_meter[type] = 0;
	} else {
		srv_meter[type] -= n;
	}

	opt = srv_max_n_utilities(type);

	if (opt < srv_n_threads_active[type]) {
		
 		event = srv_suspend_thread();
		mutex_exit(&kernel_mutex);

		os_event_wait(event);
	} else {
		mutex_exit(&kernel_mutex);
	}
}
#endif

/*************************************************************************
Implements the server console. */

ulint
srv_console(
/*========*/
			/* out: return code, not used */
	void*	arg)	/* in: argument, not used */
{
	char	command[256];

	UT_NOT_USED(arg);

	mutex_enter(&kernel_mutex);
	srv_table_reserve_slot(SRV_CONSOLE);
	mutex_exit(&kernel_mutex);

	os_event_wait(srv_sys->operational);

	for (;;) {
		scanf("%s", command);
		
		srv_inc_thread_count(SRV_CONSOLE);

		if (command[0] == 'c') {
			printf("Making checkpoint\n");

			log_make_checkpoint_at(ut_dulint_max, TRUE);

			printf("Checkpoint completed\n");

		} else if (command[0] == 'd') {
			srv_sim_disk_wait_pct = atoi(command + 1);

			printf(
			"Starting disk access simulation with pct %lu\n",
							srv_sim_disk_wait_pct);
		} else {
			printf("\nNot supported!\n");
		}

		srv_dec_thread_count(SRV_CONSOLE);
	}
	
	return(0);
}

/*************************************************************************
Creates the first communication endpoint for the server. This
first call also initializes the com0com.* module. */
810

811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901
void
srv_communication_init(
/*===================*/
	char*	endpoint)	/* in: server address */
{
	ulint	ret;
	ulint	len;

	srv_sys->endpoint = com_endpoint_create(COM_SHM);

	ut_a(srv_sys->endpoint);

	len = ODBC_DATAGRAM_SIZE;
	
	ret = com_endpoint_set_option(srv_sys->endpoint,
					COM_OPT_MAX_DGRAM_SIZE,
					(byte*)&len, sizeof(ulint));
	ut_a(ret == 0);

	ret = com_bind(srv_sys->endpoint, endpoint, ut_strlen(endpoint));
	
	ut_a(ret == 0);
}
	
/*************************************************************************
Implements the recovery utility. */
static
ulint
srv_recovery_thread(
/*================*/
			/* out: return code, not used */
	void*	arg)	/* in: not used */
{
	ulint	slot_no;
	os_event_t event;

	UT_NOT_USED(arg);
	
	slot_no = srv_table_reserve_slot(SRV_RECOVERY);

	os_event_wait(srv_sys->operational);

	for (;;) {
		/* Finish a possible recovery */

		srv_inc_thread_count(SRV_RECOVERY);

/*		recv_recovery_from_checkpoint_finish(); */

		srv_dec_thread_count(SRV_RECOVERY);

		mutex_enter(&kernel_mutex);
 		event = srv_suspend_thread();
		mutex_exit(&kernel_mutex);

		/* Wait for somebody to release this thread; (currently, this
		should never be released) */

		os_event_wait(event);
	}

	return(0);
}

/*************************************************************************
Implements the purge utility. */

ulint
srv_purge_thread(
/*=============*/
			/* out: return code, not used */
	void*	arg)	/* in: not used */
{
	UT_NOT_USED(arg);

	os_event_wait(srv_sys->operational);

	for (;;) {
		trx_purge();
	}

	return(0);
}

/*************************************************************************
Creates the utility threads. */

void
srv_create_utility_threads(void)
/*============================*/
{
902 903
/*      os_thread_t	thread;
 	os_thread_id_t	thr_id; */
904 905 906 907 908 909 910 911 912 913
	ulint		i;

	mutex_enter(&kernel_mutex);

	srv_n_threads[SRV_RECOVERY] = 1;
	srv_n_threads_active[SRV_RECOVERY] = 1;

	mutex_exit(&kernel_mutex);

	for (i = 0; i < 1; i++) {
914
	  /* thread = os_thread_create(srv_recovery_thread, NULL, &thr_id); */
915

916
	  /* ut_a(thread); */
917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980
	}

/*	thread = os_thread_create(srv_purge_thread, NULL, &thr_id);

	ut_a(thread); */
}

/*************************************************************************
Implements the communication threads. */
static
ulint
srv_com_thread(
/*===========*/
			/* out: return code; not used */
	void*	arg)	/* in: not used */
{
	byte*	msg_buf;
	byte*	addr_buf;
	ulint	msg_len;
	ulint	addr_len;
	ulint	ret;

	UT_NOT_USED(arg);

	srv_table_reserve_slot(SRV_COM);

	os_event_wait(srv_sys->operational);

	msg_buf = mem_alloc(com_endpoint_get_max_size(srv_sys->endpoint));
	addr_buf = mem_alloc(COM_MAX_ADDR_LEN);
	
	for (;;) {
		ret = com_recvfrom(srv_sys->endpoint, msg_buf,
				com_endpoint_get_max_size(srv_sys->endpoint),
				&msg_len, (char*)addr_buf, COM_MAX_ADDR_LEN,
				&addr_len);
		ut_a(ret == 0);

		srv_inc_thread_count(SRV_COM);
		
		sess_process_cli_msg(msg_buf, msg_len, addr_buf, addr_len);

/*		srv_increment_meter(SRV_RECOVERY, 1); */

		srv_dec_thread_count(SRV_COM);

		/* Release one utility thread for each utility if
		high water mark 2 is exceeded and there are no
		active queries. This is done to utilize possible
		quiet time in the server. */

		srv_release_one_if_no_queries();
	}		

	return(0);
}

/*************************************************************************
Creates the communication threads. */

void
srv_create_com_threads(void)
/*========================*/
{
981 982
  /*	os_thread_t	thread;
	os_thread_id_t	thr_id; */
983 984 985 986 987
	ulint		i;

	srv_n_threads[SRV_COM] = srv_n_com_threads;

	for (i = 0; i < srv_n_com_threads; i++) {
988
	  /* thread = os_thread_create(srv_com_thread, NULL, &thr_id); */
989
	  /* ut_a(thread); */
990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039
	}
}

/*************************************************************************
Implements the worker threads. */
static
ulint
srv_worker_thread(
/*==============*/
			/* out: return code, not used */
	void*	arg)	/* in: not used */
{
	os_event_t	event;
	
	UT_NOT_USED(arg);

	srv_table_reserve_slot(SRV_WORKER);

	os_event_wait(srv_sys->operational);

	for (;;) {
		mutex_enter(&kernel_mutex);
 		event = srv_suspend_thread();
		mutex_exit(&kernel_mutex);

		/* Wait for somebody to release this thread */
		os_event_wait(event);

		srv_inc_thread_count(SRV_WORKER);

		/* Check in the server task queue if there is work for this
		thread, and do the work */

		srv_que_task_queue_check();				

		srv_dec_thread_count(SRV_WORKER);

		/* Release one utility thread for each utility if
		high water mark 2 is exceeded and there are no
		active queries. This is done to utilize possible
		quiet time in the server. */

		srv_release_one_if_no_queries();
	}		

	return(0);
}

/*************************************************************************
Creates the worker threads. */
1040

1041 1042 1043 1044
void
srv_create_worker_threads(void)
/*===========================*/
{
1045 1046
/*	os_thread_t	thread;
	os_thread_id_t	thr_id; */
1047 1048 1049 1050 1051 1052
	ulint		i;

	srv_n_threads[SRV_WORKER] = srv_n_worker_threads;
	srv_n_threads_active[SRV_WORKER] = srv_n_worker_threads;

	for (i = 0; i < srv_n_worker_threads; i++) {
1053
	  /* thread = os_thread_create(srv_worker_thread, NULL, &thr_id); */
1054
	  /* ut_a(thread); */
1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719
	}
}

#ifdef notdefined
/*************************************************************************
Reads a keyword and a value from a file. */

ulint
srv_read_init_val(
/*==============*/
				/* out: DB_SUCCESS or error code */
	FILE*	initfile,	/* in: file pointer */
	char*	keyword,	/* in: keyword before value(s), or NULL if
				no keyword read */
	char*	str_buf,	/* in/out: buffer for a string value to read,
				buffer size must be 10000 bytes, if NULL
				then not read */
	ulint*	num_val,	/* out:	numerical value to read, if NULL
				then not read */
	ibool	print_not_err)	/* in: if TRUE, then we will not print
				error messages to console */
{		
	ulint	ret;
	char	scan_buf[10000];

	if (keyword == NULL) {

		goto skip_keyword;
	}
	
	ret = fscanf(initfile, "%9999s", scan_buf);
	
	if (ret == 0 || ret == EOF || 0 != ut_strcmp(scan_buf, keyword)) {
		if (print_not_err) {

			return(DB_ERROR);
		}
		
		printf("Error in Innobase booting: keyword %s not found\n",
							keyword);
		printf("from the initfile!\n");

		return(DB_ERROR);
	}
skip_keyword:
	if (num_val == NULL && str_buf == NULL) {

		return(DB_SUCCESS);
	}		

	ret = fscanf(initfile, "%9999s", scan_buf);
	
	if (ret == EOF || ret == 0) {
		if (print_not_err) {

			return(DB_ERROR);
		}

		printf(
	"Error in Innobase booting: could not read first value after %s\n",
								keyword);
		printf("from the initfile!\n");

		return(DB_ERROR);
	}

	if (str_buf) {
		ut_memcpy(str_buf, scan_buf, 10000);

		printf("init keyword %s value %s read\n", keyword, str_buf);

		if (!num_val) {
			return(DB_SUCCESS);
		}

		ret = fscanf(initfile, "%9999s", scan_buf);
	
		if (ret == EOF || ret == 0) {

			if (print_not_err) {

				return(DB_ERROR);
			}
			
			printf(
	"Error in Innobase booting: could not read second value after %s\n",
							keyword);
			printf("from the initfile!\n");

			return(DB_ERROR);
		}
	}

	if (ut_strlen(scan_buf) > 9) {

		if (print_not_err) {

			return(DB_ERROR);
		}

		printf(
	"Error in Innobase booting: numerical value too big after %s\n",
								keyword);
		printf("in the initfile!\n");

		return(DB_ERROR);
	}

	*num_val = (ulint)atoi(scan_buf);

	if (*num_val >= 1000000000) {

		if (print_not_err) {

			return(DB_ERROR);
		}

		printf(
	"Error in Innobase booting: numerical value too big after %s\n",
							keyword);
		printf("in the initfile!\n");

		return(DB_ERROR);
	}

	printf("init keyword %s value %lu read\n", keyword, *num_val);

	return(DB_SUCCESS);
}

/*************************************************************************
Reads keywords and values from an initfile. */

ulint
srv_read_initfile(
/*==============*/
				/* out: DB_SUCCESS or error code */
	FILE*	initfile)	/* in: file pointer */
{
	char	str_buf[10000];
	ulint	n;
	ulint	i;
	ulint	ulint_val;
	ulint	val1;
	ulint	val2;
	ulint	err;

	err = srv_read_init_val(initfile, "INNOBASE_DATA_HOME_DIR",
						str_buf, NULL, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_data_home = ut_malloc(ut_strlen(str_buf) + 1);
	ut_memcpy(srv_data_home, str_buf, ut_strlen(str_buf) + 1);
		
	err = srv_read_init_val(initfile,"TABLESPACE_NUMBER_OF_DATA_FILES",
							NULL, &n, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_n_data_files = n;

	srv_data_file_names = ut_malloc(n * sizeof(char*));
	srv_data_file_sizes = ut_malloc(n * sizeof(ulint));
	
	for (i = 0; i < n; i++) {
		err = srv_read_init_val(initfile,
				"DATA_FILE_PATH_AND_SIZE_MB",
						str_buf, &ulint_val, FALSE);
		if (err != DB_SUCCESS) return(err);

		srv_data_file_names[i] = ut_malloc(ut_strlen(str_buf) + 1);
		ut_memcpy(srv_data_file_names[i], str_buf,
						ut_strlen(str_buf) + 1);
		srv_data_file_sizes[i] = ulint_val
					* ((1024 * 1024) / UNIV_PAGE_SIZE);
	}		

	err = srv_read_init_val(initfile,
				"NUMBER_OF_MIRRORED_LOG_GROUPS", NULL,
						&srv_n_log_groups, FALSE);	
	if (err != DB_SUCCESS) return(err);

	err = srv_read_init_val(initfile,
				"NUMBER_OF_LOG_FILES_IN_GROUP", NULL,
						&srv_n_log_files, FALSE);
	if (err != DB_SUCCESS) return(err);

	err = srv_read_init_val(initfile, "LOG_FILE_SIZE_KB", NULL,
						&srv_log_file_size, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_log_file_size = srv_log_file_size / (UNIV_PAGE_SIZE / 1024);

	srv_log_group_home_dirs = ut_malloc(srv_n_log_files * sizeof(char*));

	for (i = 0; i < srv_n_log_groups; i++) {
	
		err = srv_read_init_val(initfile,
					"INNOBASE_LOG_GROUP_HOME_DIR",
							str_buf, NULL, FALSE);
		if (err != DB_SUCCESS) return(err);

		srv_log_group_home_dirs[i] = ut_malloc(ut_strlen(str_buf) + 1);
		ut_memcpy(srv_log_group_home_dirs[i], str_buf,
							ut_strlen(str_buf) + 1);
	}

	err = srv_read_init_val(initfile, "INNOBASE_LOG_ARCH_DIR",
						str_buf, NULL, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_arch_dir = ut_malloc(ut_strlen(str_buf) + 1);
	ut_memcpy(srv_arch_dir, str_buf, ut_strlen(str_buf) + 1);
	
	err = srv_read_init_val(initfile, "LOG_ARCHIVE_ON(1/0)", NULL,
						&srv_log_archive_on, FALSE);
	if (err != DB_SUCCESS) return(err);
							
	err = srv_read_init_val(initfile, "LOG_BUFFER_SIZE_KB", NULL,
						&srv_log_buffer_size, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_log_buffer_size = srv_log_buffer_size / (UNIV_PAGE_SIZE / 1024);

	err = srv_read_init_val(initfile, "FLUSH_LOG_AT_TRX_COMMIT(1/0)", NULL,
				&srv_flush_log_at_trx_commit, FALSE);
	if (err != DB_SUCCESS) return(err);
	
	err = srv_read_init_val(initfile, "BUFFER_POOL_SIZE_MB", NULL,
						&srv_pool_size, FALSE);
	if (err != DB_SUCCESS) return(err);

	srv_pool_size = srv_pool_size * ((1024 * 1024) / UNIV_PAGE_SIZE);
	
	err = srv_read_init_val(initfile, "ADDITIONAL_MEM_POOL_SIZE_MB", NULL,
						&srv_mem_pool_size, FALSE);
	if (err != DB_SUCCESS) return(err);
	
	srv_mem_pool_size = srv_mem_pool_size * 1024 * 1024;

	srv_lock_table_size = 20 * srv_pool_size;

	err = srv_read_init_val(initfile, "NUMBER_OF_FILE_IO_THREADS", NULL,
						&srv_n_file_io_threads, FALSE);
	if (err != DB_SUCCESS) return(err);
	
	err = srv_read_init_val(initfile, "SRV_RECOVER_FROM_BACKUP",
							NULL, NULL, TRUE);
	if (err == DB_SUCCESS) {
		srv_archive_recovery = TRUE;
		srv_archive_recovery_limit_lsn = ut_dulint_max;
		
		err = srv_read_init_val(initfile, NULL, NULL, &val1, TRUE);
		err = srv_read_init_val(initfile, NULL, NULL, &val2, TRUE);

		if (err == DB_SUCCESS) {
			srv_archive_recovery_limit_lsn =
					ut_dulint_create(val1, val2);
		}
	}	

	/* err = srv_read_init_val(initfile,
				"SYNC_NUMBER_OF_SPIN_WAIT_ROUNDS", NULL,
						&srv_n_spin_wait_rounds);

	err = srv_read_init_val(initfile, "SYNC_SPIN_WAIT_DELAY", NULL,
						&srv_spin_wait_delay); */
	return(DB_SUCCESS);
}

/*************************************************************************
Reads keywords and a values from an initfile. In case of an error, exits
from the process. */

void
srv_read_initfile(
/*==============*/
	FILE*	initfile)	/* in: file pointer */
{
	char	str_buf[10000];
	ulint	ulint_val;

	srv_read_init_val(initfile, FALSE, "SRV_ENDPOINT_NAME", str_buf,
								&ulint_val);
	ut_a(ut_strlen(str_buf) < COM_MAX_ADDR_LEN);
	
	ut_memcpy(srv_endpoint_name, str_buf, COM_MAX_ADDR_LEN);

	srv_read_init_val(initfile, TRUE, "SRV_N_COM_THREADS", str_buf,
						&srv_n_com_threads);

	srv_read_init_val(initfile, TRUE, "SRV_N_WORKER_THREADS", str_buf,
						&srv_n_worker_threads);

	srv_read_init_val(initfile, TRUE, "SYNC_N_SPIN_WAIT_ROUNDS", str_buf,
						&srv_n_spin_wait_rounds);

	srv_read_init_val(initfile, TRUE, "SYNC_SPIN_WAIT_DELAY", str_buf,
						&srv_spin_wait_delay);

	srv_read_init_val(initfile, TRUE, "THREAD_PRIORITY_BOOST", str_buf,
						&srv_priority_boost);

	srv_read_init_val(initfile, TRUE, "N_SPACES", str_buf, &srv_n_spaces);
	srv_read_init_val(initfile, TRUE, "N_FILES", str_buf, &srv_n_files);
	srv_read_init_val(initfile, TRUE, "FILE_SIZE", str_buf,
							&srv_file_size);

	srv_read_init_val(initfile, TRUE, "N_LOG_GROUPS", str_buf,
							&srv_n_log_groups);
	srv_read_init_val(initfile, TRUE, "N_LOG_FILES", str_buf,
							&srv_n_log_files);
	srv_read_init_val(initfile, TRUE, "LOG_FILE_SIZE", str_buf,
							&srv_log_file_size);
	srv_read_init_val(initfile, TRUE, "LOG_ARCHIVE_ON", str_buf,
							&srv_log_archive_on);
	srv_read_init_val(initfile, TRUE, "LOG_BUFFER_SIZE", str_buf,
						&srv_log_buffer_size);
	srv_read_init_val(initfile, TRUE, "FLUSH_LOG_AT_TRX_COMMIT", str_buf,
						&srv_flush_log_at_trx_commit);
	
	
	srv_read_init_val(initfile, TRUE, "POOL_SIZE", str_buf,
						&srv_pool_size);
	srv_read_init_val(initfile, TRUE, "MEM_POOL_SIZE", str_buf,
						&srv_mem_pool_size);
	srv_read_init_val(initfile, TRUE, "LOCK_TABLE_SIZE", str_buf,
						&srv_lock_table_size);

	srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_PCT", str_buf,
						&srv_sim_disk_wait_pct);

	srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_LEN", str_buf,
						&srv_sim_disk_wait_len);

	srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_BY_YIELD", str_buf,
						&srv_sim_disk_wait_by_yield);

	srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_BY_WAIT", str_buf,
						&srv_sim_disk_wait_by_wait);

	srv_read_init_val(initfile, TRUE, "MEASURE_CONTENTION", str_buf,
						&srv_measure_contention);

	srv_read_init_val(initfile, TRUE, "MEASURE_BY_SPIN", str_buf,
						&srv_measure_by_spin);
	

	srv_read_init_val(initfile, TRUE, "PRINT_THREAD_RELEASES", str_buf,
						&srv_print_thread_releases);
	
	srv_read_init_val(initfile, TRUE, "PRINT_LOCK_WAITS", str_buf,
						&srv_print_lock_waits);
	if (srv_print_lock_waits) {
		lock_print_waits = TRUE;
	}
	
	srv_read_init_val(initfile, TRUE, "PRINT_BUF_IO", str_buf,
						&srv_print_buf_io);
	if (srv_print_buf_io) {
		buf_debug_prints = TRUE;
	}	
	
	srv_read_init_val(initfile, TRUE, "PRINT_LOG_IO", str_buf,
						&srv_print_log_io);
	if (srv_print_log_io) {
		log_debug_writes = TRUE;
	}	
	
	srv_read_init_val(initfile, TRUE, "PRINT_PARSED_SQL", str_buf,
						&srv_print_parsed_sql);
	if (srv_print_parsed_sql) {
		pars_print_lexed = TRUE;
	}

	srv_read_init_val(initfile, TRUE, "PRINT_LATCH_WAITS", str_buf,
						&srv_print_latch_waits);

	srv_read_init_val(initfile, TRUE, "TEST_EXTRA_MUTEXES", str_buf,
						&srv_test_extra_mutexes);
	srv_read_init_val(initfile, TRUE, "TEST_NOCACHE", str_buf,
						&srv_test_nocache);
	srv_read_init_val(initfile, TRUE, "TEST_CACHE_EVICT", str_buf,
						&srv_test_cache_evict);

	srv_read_init_val(initfile, TRUE, "TEST_SYNC", str_buf,
						&srv_test_sync);
	srv_read_init_val(initfile, TRUE, "TEST_N_THREADS", str_buf,
						&srv_test_n_threads);
	srv_read_init_val(initfile, TRUE, "TEST_N_LOOPS", str_buf,
						&srv_test_n_loops);
	srv_read_init_val(initfile, TRUE, "TEST_N_FREE_RNDS", str_buf,
						&srv_test_n_free_rnds);
	srv_read_init_val(initfile, TRUE, "TEST_N_RESERVED_RNDS", str_buf,
						&srv_test_n_reserved_rnds);
	srv_read_init_val(initfile, TRUE, "TEST_N_MUTEXES", str_buf,
						&srv_test_n_mutexes);
	srv_read_init_val(initfile, TRUE, "TEST_ARRAY_SIZE", str_buf,
						&srv_test_array_size);
}
#endif

/*************************************************************************
Initializes the server. */
static
void
srv_init(void)
/*==========*/
{
	srv_slot_t*	slot;
	ulint		i;

	srv_sys = mem_alloc(sizeof(srv_sys_t));

	kernel_mutex_temp = mem_alloc(sizeof(mutex_t));
	mutex_create(&kernel_mutex);
	mutex_set_level(&kernel_mutex, SYNC_KERNEL);
	
	srv_sys->threads = mem_alloc(OS_THREAD_MAX_N * sizeof(srv_slot_t));

	for (i = 0; i < OS_THREAD_MAX_N; i++) {
		slot = srv_table_get_nth_slot(i);
		slot->in_use = FALSE;
		slot->event = os_event_create(NULL);
		ut_a(slot->event);
	}

	srv_mysql_table = mem_alloc(OS_THREAD_MAX_N * sizeof(srv_slot_t));

	for (i = 0; i < OS_THREAD_MAX_N; i++) {
		slot = srv_mysql_table + i;
		slot->in_use = FALSE;
		slot->event = os_event_create(NULL);
		ut_a(slot->event);
	}

	srv_lock_timeout_thread_event = os_event_create(NULL);
	
	for (i = 0; i < SRV_MASTER + 1; i++) {
		srv_n_threads_active[i] = 0;
		srv_n_threads[i] = 0;
		srv_meter[i] = 30;
		srv_meter_low_water[i] = 50;
		srv_meter_high_water[i] = 100;
		srv_meter_high_water2[i] = 200;
		srv_meter_foreground[i] = 250;
	}
	
	srv_sys->operational = os_event_create(NULL);

	ut_a(srv_sys->operational);

	UT_LIST_INIT(srv_sys->tasks);
}	
	
/*************************************************************************
Initializes the synchronization primitives, memory system, and the thread
local storage. */
static
void
srv_general_init(void)
/*==================*/
{
	sync_init();
	mem_init(srv_mem_pool_size);
	thr_local_init();
}

/*************************************************************************
Normalizes init parameter values to use units we use inside Innobase. */
static
ulint
srv_normalize_init_values(void)
/*===========================*/
				/* out: DB_SUCCESS or error code */
{
	ulint	n;
	ulint	i;

	n = srv_n_data_files;
	
	for (i = 0; i < n; i++) {
		srv_data_file_sizes[i] = srv_data_file_sizes[i]
					* ((1024 * 1024) / UNIV_PAGE_SIZE);
	}		

	srv_log_file_size = srv_log_file_size / UNIV_PAGE_SIZE;

	srv_log_buffer_size = srv_log_buffer_size / UNIV_PAGE_SIZE;

	srv_pool_size = srv_pool_size / UNIV_PAGE_SIZE;
	
	srv_lock_table_size = 20 * srv_pool_size;

	return(DB_SUCCESS);
}

/*************************************************************************
Boots the Innobase server. */

ulint
srv_boot(void)
/*==========*/
			/* out: DB_SUCCESS or error code */
{
	ulint	err;

	/* Transform the init parameter values given by MySQL to
	use units we use inside Innobase: */
	
	err = srv_normalize_init_values();

	if (err != DB_SUCCESS) {
		return(err);
	}
	
	/* Initialize synchronization primitives, memory management, and thread
	local storage */
	
	srv_general_init();

	/* Initialize this module */

	srv_init();

	/* Reserve the first slot for the current thread, i.e., the master
	thread */

	srv_table_reserve_slot(SRV_MASTER);

	return(DB_SUCCESS);
}

/*************************************************************************
Reserves a slot in the thread table for the current MySQL OS thread.
NOTE! The server mutex has to be reserved by the caller! */
static
srv_slot_t*
srv_table_reserve_slot_for_mysql(void)
/*==================================*/
			/* out: reserved slot */
{
	srv_slot_t*	slot;
	ulint		i;

	i = 0;
	slot = srv_mysql_table + i;

	while (slot->in_use) {
		i++;
		ut_a(i < OS_THREAD_MAX_N);
		
		slot = srv_mysql_table + i;
	}

	ut_a(slot->in_use == FALSE);
	
	slot->in_use = TRUE;
	slot->id = os_thread_get_curr_id();
	slot->handle = os_thread_get_curr();

	return(slot);
}

/*******************************************************************
Puts a MySQL OS thread to wait for a lock to be released. */

ibool
srv_suspend_mysql_thread(
/*=====================*/
				/* out: TRUE if the lock wait timeout was
				exceeded */
	que_thr_t*	thr)	/* in: query thread associated with
				the MySQL OS thread */
{
	srv_slot_t*	slot;
	os_event_t	event;
	double		wait_time;

	ut_ad(!mutex_own(&kernel_mutex));

	os_event_set(srv_lock_timeout_thread_event);

	mutex_enter(&kernel_mutex);

	if (thr->state == QUE_THR_RUNNING) {

		/* The lock has already been released: no need to suspend */

		mutex_exit(&kernel_mutex);

		return(FALSE);
	}
	
	slot = srv_table_reserve_slot_for_mysql();

	event = slot->event;
	
	slot->thr = thr;

	os_event_reset(event);	

	slot->suspend_time = ut_time();

	/* Wake the lock timeout monitor thread, if it is suspended */

	os_event_set(srv_lock_timeout_thread_event);
	
	mutex_exit(&kernel_mutex);

	/* Wait for the release */
	
	os_event_wait(event);

	mutex_enter(&kernel_mutex);

	/* Release the slot for others to use */
	
	slot->in_use = FALSE;

	wait_time = ut_difftime(ut_time(), slot->suspend_time);
	
	mutex_exit(&kernel_mutex);

	if (srv_lock_wait_timeout < 100000000 && 
	    			wait_time > (double)srv_lock_wait_timeout) {
	   	return(TRUE);
	}

	return(FALSE);
}

/************************************************************************
Releases a MySQL OS thread waiting for a lock to be released, if the
thread is already suspended. */

void
srv_release_mysql_thread_if_suspended(
/*==================================*/
	que_thr_t*	thr)	/* in: query thread associated with the
				MySQL OS thread  */
{
	srv_slot_t*	slot;
	ulint		i;
	
	ut_ad(mutex_own(&kernel_mutex));

	for (i = 0; i < OS_THREAD_MAX_N; i++) {

		slot = srv_mysql_table + i;

		if (slot->in_use && slot->thr == thr) {
			/* Found */

			os_event_set(slot->event);

			return;
		}
	}

	/* not found */
}

/*************************************************************************
A thread which wakes up threads whose lock wait may have lasted too long. */

1720 1721 1722
#ifndef __WIN__
void*
#else
1723
ulint
1724
#endif
1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788
srv_lock_timeout_monitor_thread(
/*============================*/
			/* out: a dummy parameter */
	void*	arg)	/* in: a dummy parameter required by
			os_thread_create */
{
	ibool		some_waits;
	srv_slot_t*	slot;
	double		wait_time;
	ulint		i;

	UT_NOT_USED(arg);
loop:
	/* When someone is waiting for a lock, we wake up every second
	and check if a timeout has passed for a lock wait */

	os_thread_sleep(1000000);
			
	mutex_enter(&kernel_mutex);

	some_waits = FALSE;

	/* Check of all slots if a thread is waiting there, and if it
	has exceeded the time limit */
	
	for (i = 0; i < OS_THREAD_MAX_N; i++) {

		slot = srv_mysql_table + i;

		if (slot->in_use) {
			some_waits = TRUE;

			wait_time = ut_difftime(ut_time(), slot->suspend_time);
			
			if (srv_lock_wait_timeout < 100000000 && 
	    			(wait_time > (double) srv_lock_wait_timeout
						|| wait_time < 0)) {

				/* Timeout exceeded or a wrap over in system
				time counter: cancel the lock request queued
				by the transaction; NOTE that currently only
				a record lock request can be waiting in
				MySQL! */

				lock_rec_cancel(
				    thr_get_trx(slot->thr)->wait_lock);
			}
		}
	}

	os_event_reset(srv_lock_timeout_thread_event);

	mutex_exit(&kernel_mutex);

	if (some_waits) {
		goto loop;
	}

	/* No one was waiting for a lock: suspend this thread */
	
	os_event_wait(srv_lock_timeout_thread_event);

	goto loop;

1789 1790 1791
#ifndef __WIN__
        return(NULL);
#else
1792
	return(0);
1793
#endif
1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821
}

/***********************************************************************
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
in the MySQL interface. Note that there is a small chance that the master
thread stays suspended (we do not protect our operation with the kernel
mutex, for performace reasons). */

void
srv_active_wake_master_thread(void)
/*===============================*/
{
	srv_activity_count++;
			
	if (srv_n_threads_active[SRV_MASTER] == 0) {

		mutex_enter(&kernel_mutex);

		srv_release_threads(SRV_MASTER, 1);

		mutex_exit(&kernel_mutex);
	}
}

/*************************************************************************
The master thread controlling the server. */

1822 1823 1824
#ifndef __WIN__
void*
#else
1825
ulint
1826
#endif
1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965
srv_master_thread(
/*==============*/
			/* out: a dummy parameter */
	void*	arg)	/* in: a dummy parameter required by
			os_thread_create */
{
	os_event_t	event;
	ulint		old_activity_count;
	ulint		n_pages_purged;
	ulint		n_bytes_merged;
	ulint		n_pages_flushed;
	ulint		n_bytes_archived;
	ulint		i;
	
	UT_NOT_USED(arg);

	srv_table_reserve_slot(SRV_MASTER);	

	mutex_enter(&kernel_mutex);

	srv_n_threads_active[SRV_MASTER]++;

	mutex_exit(&kernel_mutex);

	os_event_set(srv_sys->operational);
loop:
	mutex_enter(&kernel_mutex);

	old_activity_count = srv_activity_count;

	mutex_exit(&kernel_mutex);

	/* We run purge every 10 seconds, even if the server were active: */

	for (i = 0; i < 10; i++) {
		os_thread_sleep(1000000);

		if (srv_activity_count == old_activity_count) {

			if (srv_print_thread_releases) {
				printf("Master thread wakes up!\n");
			}

			goto background_loop;
		}
	}

	if (srv_print_thread_releases) {
		printf("Master thread wakes up!\n");
	}

	n_pages_purged = 1;

	while (n_pages_purged) {
		n_pages_purged = trx_purge();
		/* TODO: replace this by a check if we are running
							out of file space! */
	}

background_loop:
	/* In this loop we run background operations while the server
	is quiet */

	mutex_enter(&kernel_mutex);
	if (srv_activity_count != old_activity_count) {
		mutex_exit(&kernel_mutex);
		goto loop;
	}
	old_activity_count = srv_activity_count;
	mutex_exit(&kernel_mutex);

	/* The server has been quiet for a while: start running background
	operations */
		
	n_pages_purged = trx_purge();

	mutex_enter(&kernel_mutex);
	if (srv_activity_count != old_activity_count) {
		mutex_exit(&kernel_mutex);
		goto loop;
	}
	mutex_exit(&kernel_mutex);

	n_bytes_merged = ibuf_contract(TRUE);

	mutex_enter(&kernel_mutex);
	if (srv_activity_count != old_activity_count) {
		mutex_exit(&kernel_mutex);
		goto loop;
	}
	mutex_exit(&kernel_mutex);
	
	n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 20, ut_dulint_max);

	mutex_enter(&kernel_mutex);
	if (srv_activity_count != old_activity_count) {
		mutex_exit(&kernel_mutex);
		goto loop;
	}
	mutex_exit(&kernel_mutex);
	
	buf_flush_wait_batch_end(BUF_FLUSH_LIST);

	log_checkpoint(TRUE, FALSE);

	mutex_enter(&kernel_mutex);
	if (srv_activity_count != old_activity_count) {
		mutex_exit(&kernel_mutex);
		goto loop;
	}
	mutex_exit(&kernel_mutex);
	
	log_archive_do(FALSE, &n_bytes_archived);

	if (n_pages_purged + n_bytes_merged + n_pages_flushed
						+ n_bytes_archived != 0) {
		goto background_loop;
	}
		
/*	mem_print_new_info();

	fsp_print(0);
*/
#ifdef UNIV_SEARCH_PERF_STAT
/*	btr_search_print_info(); */
#endif
	/* There is no work for background operations either: suspend
	master thread to wait for more server activity */
	
	mutex_enter(&kernel_mutex);

	event = srv_suspend_thread();

	mutex_exit(&kernel_mutex);

	os_event_wait(event);

	goto loop;

1966 1967 1968
#ifndef __WIN__
        return(NULL);
#else
1969
	return(0);
1970
#endif
1971
}