branches/zip: Mantis issue #197 - Make srv_spin_wait_delay configurable

New parameter innodb_spin_wait_delay to set the maximum delay between
polling for a spin lock. 5 is the default.

Approved by: Marko (on IM)

handler/ha_innodb.cc

@@ -9640,6 +9640,11 @@ static MYSQL_SYSVAR_ULONG(sync_spin_loops, srv_n_spin_wait_rounds,
   "Count of spin-loop rounds in InnoDB mutexes",
   NULL, NULL, 20L, 0L, ~0L, 0);
 
+static MYSQL_SYSVAR_ULONG(spin_wait_delay, srv_spin_wait_delay,
+  PLUGIN_VAR_OPCMDARG,
+  "Maximum delay between polling for a spin lock (5 by default)",
+  NULL, NULL, 5L, 0L, ~0L, 0);
+
 static MYSQL_SYSVAR_ULONG(thread_concurrency, srv_thread_concurrency,
   PLUGIN_VAR_RQCMDARG,
   "Helps in performance tuning in heavily concurrent environments. Sets the maximum number of threads allowed inside InnoDB. Value 0 will disable the thread throttling.",
@@ -9724,6 +9729,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(strict_mode),
   MYSQL_SYSVAR(support_xa),
   MYSQL_SYSVAR(sync_spin_loops),
+  MYSQL_SYSVAR(spin_wait_delay),
   MYSQL_SYSVAR(table_locks),
   MYSQL_SYSVAR(thread_concurrency),
   MYSQL_SYSVAR(thread_sleep_delay),

include/srv0srv.h

@@ -185,7 +185,7 @@ extern ibool	srv_error_monitor_active;
 extern ulong	srv_n_spin_wait_rounds;
 extern ulong	srv_n_free_tickets_to_enter;
 extern ulong	srv_thread_sleep_delay;
-extern ulint	srv_spin_wait_delay;
+extern ulong	srv_spin_wait_delay;
 extern ibool	srv_priority_boost;
 
 extern	ulint	srv_mem_pool_size;

srv/srv0srv.c

@@ -341,7 +341,7 @@ UNIV_INTERN ulong	srv_replication_delay		= 0;
 UNIV_INTERN ulong	srv_n_spin_wait_rounds	= 20;
 UNIV_INTERN ulong	srv_n_free_tickets_to_enter = 500;
 UNIV_INTERN ulong	srv_thread_sleep_delay = 10000;
-UNIV_INTERN ulint	srv_spin_wait_delay	= 5;
+UNIV_INTERN ulong	srv_spin_wait_delay	= 5;
 UNIV_INTERN ibool	srv_priority_boost	= TRUE;
 
 #ifdef UNIV_DEBUG