*** postgresql-8.0.3/src/include/storage/s_lock.h.orig	Sun Aug 28 20:41:44 2005
--- postgresql-8.0.3/src/include/storage/s_lock.h	Fri Sep  9 14:58:44 2005
***************
*** 120,132 ****
  {
  	register slock_t _res = 1;
  
! 	/* Use a non-locking test before asserting the bus lock */
  	__asm__ __volatile__(
- 		"	cmpb	$0,%1	\n"
- 		"	jne		1f		\n"
- 		"	lock			\n"
  		"	xchgb	%0,%1	\n"
- 		"1: \n"
  :		"+q"(_res), "+m"(*lock)
  :
  :		"memory", "cc");
--- 120,128 ----
  {
  	register slock_t _res = 1;
  
! 	/* xchg implies a LOCK prefix, so no need to say LOCK explicitly */
  	__asm__ __volatile__(
  		"	xchgb	%0,%1	\n"
  :		"+q"(_res), "+m"(*lock)
  :
  :		"memory", "cc");
*** postgresql-8.0.3/src/backend/storage/lmgr/s_lock.c.orig	Fri Aug 26 10:47:35 2005
--- postgresql-8.0.3/src/backend/storage/lmgr/s_lock.c	Sat Sep 10 19:19:46 2005
***************
*** 17,22 ****
--- 17,23 ----
  
  #include <time.h>
  #include <unistd.h>
+ #include <sched.h>
  
  #include "storage/s_lock.h"
  #include "miscadmin.h"
***************
*** 83,89 ****
  
  	int			spins = 0;
  	int			delays = 0;
! 	int			cur_delay = MIN_DELAY_CSEC;
  
  	while (TAS(lock))
  	{
--- 84,90 ----
  
  	int			spins = 0;
  	int			delays = 0;
! 	int			cur_delay = 0;
  
  	while (TAS(lock))
  	{
***************
*** 96,102 ****
  			if (++delays > NUM_DELAYS)
  				s_lock_stuck(lock, file, line);
  
! 			pg_usleep(cur_delay * 10000L);
  
  #if defined(S_LOCK_TEST)
  			fprintf(stdout, "*");
--- 97,110 ----
  			if (++delays > NUM_DELAYS)
  				s_lock_stuck(lock, file, line);
  
! 			if (cur_delay == 0)
! 			{
! 			  /* first time through, try just a sched_yield */
! 			  sched_yield();
! 			  cur_delay = MIN_DELAY_CSEC;
! 			}
! 			else
! 			  pg_usleep(cur_delay * 10000L);
  
  #if defined(S_LOCK_TEST)
  			fprintf(stdout, "*");