Backport innodb_max_purge_lag from 4.1

innobase/include/srv0srv.h:
  Add configuration parameter srv_max_purge_lag.
  Add global variable srv_dml_needed_delay.
innobase/include/trx0sys.h:
  Add trx_sys->rseg_history_len
innobase/row/row0mysql.c:
  Add row_mysql_delay_if_needed() for delaying INSERTs, UPDATEs and
  DELETEs for srv_dml_needed_delay microseconds.
innobase/srv/srv0srv.c:
  Define global variable srv_dml_needed_delay.
  Define configuration parameter srv_max_purge_lag.
innobase/trx/trx0purge.c:
  Update trx_sys->rseg_history_len.
  trx_purge(): Compute srv_dml_needed_delay from srv_max_purge_lag
  and trx_sys->rseg_history_len.
innobase/trx/trx0rseg.c:
  Initialize trx_sys->rseg_history_len at InnoDB start-up.
sql/ha_innodb.h:
  Add configuration parameter srv_max_purge_lag.
sql/mysqld.cc:
  Add startup option innodb_max_purge_lag,
  with default value 0 (meaning infinite, disabling the feature).
sql/set_var.cc:
  Add global variable innodb_max_purge_lag.

3 files changed, 11 insertions, 0 deletions

diff --git a/sql/ha_innodb.h b/sql/ha_innodb.h
index 5736f70c65c..74acc0640c9 100644
--- a/sql/ha_innodb.h
+++ b/sql/ha_innodb.h
@@ -207,6 +207,7 @@ extern my_bool innobase_log_archive,
                innobase_create_status_file;
 extern "C" {
 extern ulong srv_max_buf_pool_modified_pct;
+extern ulong srv_max_purge_lag;
 }
 
 extern TYPELIB innobase_lock_typelib;
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 5838bd909dd..d36b441ac9a 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -3520,6 +3520,7 @@ enum options_mysqld {
   OPT_INNODB_LOG_BUFFER_SIZE,
   OPT_INNODB_BUFFER_POOL_SIZE,
   OPT_INNODB_ADDITIONAL_MEM_POOL_SIZE,
+  OPT_INNODB_MAX_PURGE_LAG,
   OPT_INNODB_FILE_IO_THREADS,
   OPT_INNODB_LOCK_WAIT_TIMEOUT,
   OPT_INNODB_THREAD_CONCURRENCY,
@@ -3700,6 +3701,11 @@ struct my_option my_long_options[] =
   {"innodb_max_dirty_pages_pct", OPT_INNODB_MAX_DIRTY_PAGES_PCT,
    "Percentage of dirty pages allowed in bufferpool", (gptr*) &srv_max_buf_pool_modified_pct,
    (gptr*) &srv_max_buf_pool_modified_pct, 0, GET_ULONG, REQUIRED_ARG, 90, 0, 100, 0, 0, 0},
+  {"innodb_max_purge_lag", OPT_INNODB_MAX_PURGE_LAG,
+   "",
+   (gptr*) &srv_max_purge_lag,
+   (gptr*) &srv_max_purge_lag, 0, GET_LONG, REQUIRED_ARG, 0, 0, ~0L,
+   0, 1L, 0},
   {"innodb_table_locks", OPT_INNODB_TABLE_LOCKS,
    "If Innodb should enforce LOCK TABLE",
    (gptr*) &global_system_variables.innodb_table_locks,
diff --git a/sql/set_var.cc b/sql/set_var.cc
index a6a5ea72c71..d5aadbfbdab 100644
--- a/sql/set_var.cc
+++ b/sql/set_var.cc
@@ -263,6 +263,8 @@ sys_var_thd_ulong	sys_net_wait_timeout("wait_timeout",
 #ifdef HAVE_INNOBASE_DB
 sys_var_long_ptr        sys_innodb_max_dirty_pages_pct("innodb_max_dirty_pages_pct",
                                                         &srv_max_buf_pool_modified_pct);
+sys_var_long_ptr	sys_innodb_max_purge_lag("innodb_max_purge_lag",
+							&srv_max_purge_lag);
 sys_var_thd_bool	sys_innodb_table_locks("innodb_table_locks",
                                                &SV::innodb_table_locks);
 #endif 					     
@@ -451,6 +453,7 @@ sys_var *sys_variables[]=
   &sys_os,
 #ifdef HAVE_INNOBASE_DB
   &sys_innodb_max_dirty_pages_pct,
+  &sys_innodb_max_purge_lag,
   &sys_innodb_table_locks,
 #endif    
   &sys_unique_checks
@@ -523,6 +526,7 @@ struct show_var_st init_vars[]= {
   {"innodb_log_group_home_dir", (char*) &innobase_log_group_home_dir, SHOW_CHAR_PTR},
   {"innodb_mirrored_log_groups", (char*) &innobase_mirrored_log_groups, SHOW_LONG},
   {sys_innodb_max_dirty_pages_pct.name, (char*) &sys_innodb_max_dirty_pages_pct, SHOW_SYS},
+  {sys_innodb_max_purge_lag.name, (char*) &sys_innodb_max_purge_lag, SHOW_SYS},
   {sys_innodb_table_locks.name, (char*) &sys_innodb_table_locks, SHOW_SYS},
 #endif
   {sys_interactive_timeout.name,(char*) &sys_interactive_timeout,   SHOW_SYS},