Commit e3f0690d authored by unknown's avatar unknown
Browse files

Applied patch recieved from Marko: 

 Make innodb_thread_concurrency 0 by default, and extend the usable
 range from 0 to 1000 (0 disables the thread throttling).


innobase/include/srv0srv.h:
  Remove SRV_CONCURRENCY_THRESHOLD. The magic value is 0 from now on.
innobase/srv/srv0srv.c:
  Remove SRV_CONCURRENCY_THRESHOLD. The magic value is 0 from now on.
mysql-test/r/innodb.result:
  innodb_thread_concurrency is 0..1000 now, and the default is 0.
mysql-test/t/innodb.test:
  innodb_thread_concurrency is 0..1000 now.
sql/ha_innodb.cc:
  Remove SRV_CONCURRENCY_THRESHOLD. The magic value is 0 from now on.
sql/mysqld.cc:
  innodb_thread_concurrency is 0..1000 now, and 0 (the default)
   disables the thread throttling.
parent 74f499fa

innobase/include/srv0srv.h

+0 −1
Original line number Diff line number Diff line
@@ -195,7 +195,6 @@ extern mutex_t* kernel_mutex_temp;/* mutex protecting the server, trx structs, 
#define kernel_mutex (*kernel_mutex_temp)



#define SRV_MAX_N_IO_THREADS	100

#define SRV_CONCURRENCY_THRESHOLD	20

				

/* Array of English strings describing the current state of an

i/o handler thread */

innobase/srv/srv0srv.c

+5 −4
Original line number Diff line number Diff line
@@ -258,9 +258,10 @@ threads waiting for locks are not counted into the number because otherwise 
we could get a deadlock. MySQL creates a thread for each user session, and

semaphore contention and convoy problems can occur withput this restriction.

Value 10 should be good if there are less than 4 processors + 4 disks in the

computer. Bigger computers need bigger values. */

computer. Bigger computers need bigger values. Value 0 will disable the

concurrency check. */



ulong	srv_thread_concurrency	= SRV_CONCURRENCY_THRESHOLD;

ulong	srv_thread_concurrency	= 0;

ulong   srv_commit_concurrency  = 0;



os_fast_mutex_t	srv_conc_mutex;		/* this mutex protects srv_conc data
@@ -1141,7 +1142,7 @@ srv_conc_force_enter_innodb( 
	trx_t*	trx)	/* in: transaction object associated with the

			thread */

{

	if (srv_thread_concurrency >= SRV_CONCURRENCY_THRESHOLD) {

	if (UNIV_LIKELY(!srv_thread_concurrency)) {

	

		return;

	}
@@ -1167,7 +1168,7 @@ srv_conc_force_exit_innodb( 
{

	srv_conc_slot_t*	slot	= NULL;



	if (srv_thread_concurrency >= SRV_CONCURRENCY_THRESHOLD) {

	if (UNIV_LIKELY(!srv_thread_concurrency)) {

	

		return;

	}

mysql-test/r/innodb.result

+3 −3
Original line number Diff line number Diff line
@@ -1821,15 +1821,15 @@ Variable_name Value 
innodb_sync_spin_loops	20

show variables like "innodb_thread_concurrency";

Variable_name	Value

innodb_thread_concurrency	20

set global innodb_thread_concurrency=1000;

innodb_thread_concurrency	0

set global innodb_thread_concurrency=1001;

show variables like "innodb_thread_concurrency";

Variable_name	Value

innodb_thread_concurrency	1000

set global innodb_thread_concurrency=0;

show variables like "innodb_thread_concurrency";

Variable_name	Value

innodb_thread_concurrency	1

innodb_thread_concurrency	0

set global innodb_thread_concurrency=16;

show variables like "innodb_thread_concurrency";

Variable_name	Value

mysql-test/t/innodb.test

+1 −1
Original line number Diff line number Diff line
@@ -1316,7 +1316,7 @@ show variables like "innodb_sync_spin_loops"; 


# Test for innodb_thread_concurrency variable

show variables like "innodb_thread_concurrency";

set global innodb_thread_concurrency=1000;

set global innodb_thread_concurrency=1001;

show variables like "innodb_thread_concurrency";

set global innodb_thread_concurrency=0;

show variables like "innodb_thread_concurrency";

sql/ha_innodb.cc

+2 −2
Original line number Diff line number Diff line
@@ -338,7 +338,7 @@ innodb_srv_conc_enter_innodb( 
/*=========================*/

	trx_t*	trx)	/* in: transaction handle */

{

	if (UNIV_LIKELY(srv_thread_concurrency >= SRV_CONCURRENCY_THRESHOLD)) {

	if (UNIV_LIKELY(!srv_thread_concurrency)) {



		return;

	}
@@ -355,7 +355,7 @@ innodb_srv_conc_exit_innodb( 
/*========================*/

	trx_t*	trx)	/* in: transaction handle */

{

	if (UNIV_LIKELY(srv_thread_concurrency >= SRV_CONCURRENCY_THRESHOLD)) {

	if (UNIV_LIKELY(!srv_thread_concurrency)) {



		return;

	}