#At file:///home/acorreia/workspace.sun/playground.mysql/mysql-5.0.68-custom_build/
2704 Alfranio Correia 2008-11-13
BUG#40337 Fsyncing master and relay log to disk after every
event is too slow.
Introduced a recovery mechanism that throws away relay-log.bin* retrieved
from a master in case of a crash and updates the master.info based on
the relay.info. This is done because such files may be corrupted after
a crash.
It is advisalbe to use this feature, when the parameter --syn-relay-log-info = 1.
modified:
mysql-test/r/rpl_flush_log_loop.result
sql/mysql_priv.h
sql/mysqld.cc
sql/set_var.cc
sql/slave.cc
=== modified file 'mysql-test/r/rpl_flush_log_loop.result'
--- a/mysql-test/r/rpl_flush_log_loop.result 2007-10-10 07:21:11 +0000
+++ b/mysql-test/r/rpl_flush_log_loop.result 2008-11-13 20:19:09 +0000
@@ -10,6 +10,7 @@ relay_log MYSQLTEST_VARDIR/master-data/r
relay_log_index
relay_log_info_file relay-log.info
relay_log_purge ON
+relay_log_recovery OFF
relay_log_space_limit 0
stop slave;
change master to master_host='127.0.0.1',master_user='root',
=== modified file 'sql/mysql_priv.h'
--- a/sql/mysql_priv.h 2008-10-02 11:57:52 +0000
+++ b/sql/mysql_priv.h 2008-11-13 20:19:09 +0000
@@ -1314,6 +1314,7 @@ extern ulong expire_logs_days, sync_binl
extern ulong opt_tc_log_size, tc_log_max_pages_used, tc_log_page_size;
extern ulong tc_log_page_waits;
extern my_bool relay_log_purge, opt_innodb_safe_binlog, opt_innodb;
+extern my_bool relay_log_recovery;
extern uint test_flags,select_errors,ha_open_options;
extern uint protocol_version, mysqld_port, dropping_tables;
extern uint delay_key_write_options, lower_case_table_names;
=== modified file 'sql/mysqld.cc'
--- a/sql/mysqld.cc 2008-08-26 08:32:43 +0000
+++ b/sql/mysqld.cc 2008-11-13 20:19:09 +0000
@@ -404,7 +404,8 @@ ulong opt_ndb_cache_check_time;
const char *opt_ndb_mgmd;
ulong opt_ndb_nodeid;
#endif
-my_bool opt_readonly, use_temp_pool, relay_log_purge;
+my_bool opt_readonly, use_temp_pool, relay_log_purge;
+my_bool relay_log_recovery;
my_bool opt_sync_frm, opt_allow_suspicious_udfs;
my_bool opt_secure_auth= 0;
char* opt_secure_file_priv= 0;
@@ -4918,6 +4919,7 @@ enum options_mysqld
OPT_QUERY_CACHE_TYPE, OPT_QUERY_CACHE_WLOCK_INVALIDATE, OPT_RECORD_BUFFER,
OPT_RECORD_RND_BUFFER, OPT_DIV_PRECINCREMENT, OPT_RELAY_LOG_SPACE_LIMIT,
OPT_RELAY_LOG_PURGE,
+ OPT_RELAY_LOG_RECOVERY,
OPT_SLAVE_NET_TIMEOUT, OPT_SLAVE_COMPRESSED_PROTOCOL, OPT_SLOW_LAUNCH_TIME,
OPT_SLAVE_TRANS_RETRIES, OPT_READONLY, OPT_DEBUGGING,
OPT_SORT_BUFFER, OPT_TABLE_CACHE,
@@ -6302,6 +6304,11 @@ The minimum value for this variable is 4
(gptr*) &relay_log_purge,
(gptr*) &relay_log_purge, 0, GET_BOOL, NO_ARG,
1, 0, 1, 0, 1, 0},
+ {"relay_log_recovery", OPT_RELAY_LOG_RECOVERY,
+ "Enables automatic relay log recovery right after the database startup, which means that the IO Thread starts re-fetching from the master right after the last transaction processed.",
+ (gptr*) &relay_log_recovery,
+ (gptr*) &relay_log_recovery, 0, GET_BOOL, NO_ARG,
+ 0, 0, 1, 0, 1, 0},
{"relay_log_space_limit", OPT_RELAY_LOG_SPACE_LIMIT,
"Maximum space to use for all relay logs.",
(gptr*) &relay_log_space_limit,
=== modified file 'sql/set_var.cc'
--- a/sql/set_var.cc 2008-08-25 12:11:59 +0000
+++ b/sql/set_var.cc 2008-11-13 20:19:09 +0000
@@ -323,6 +323,8 @@ sys_var_thd_ulong sys_div_precincrement(
#ifdef HAVE_REPLICATION
sys_var_bool_ptr sys_relay_log_purge("relay_log_purge",
&relay_log_purge);
+sys_var_bool_ptr sys_relay_log_recovery("relay_log_recovery",
+ &relay_log_recovery);
#endif
sys_var_long_ptr sys_rpl_recovery_rank("rpl_recovery_rank",
&rpl_recovery_rank);
@@ -733,6 +735,7 @@ sys_var *sys_variables[]=
&sys_read_rnd_buff_size,
#ifdef HAVE_REPLICATION
&sys_relay_log_purge,
+ &sys_relay_log_recovery,
#endif
&sys_rpl_recovery_rank,
&sys_safe_updates,
@@ -1052,6 +1055,7 @@ struct show_var_st init_vars[]= {
{"relay_log_index", (char*) &opt_relaylog_index_name, SHOW_CHAR_PTR},
{"relay_log_info_file", (char*) &relay_log_info_file, SHOW_CHAR_PTR},
{sys_relay_log_purge.name, (char*) &sys_relay_log_purge, SHOW_SYS},
+ {sys_relay_log_recovery.name, (char*) &sys_relay_log_recovery, SHOW_SYS},
{"relay_log_space_limit", (char*) &relay_log_space_limit, SHOW_LONGLONG},
#endif
{sys_rpl_recovery_rank.name,(char*) &sys_rpl_recovery_rank, SHOW_SYS},
=== modified file 'sql/slave.cc'
--- a/sql/slave.cc 2008-03-28 20:01:05 +0000
+++ b/sql/slave.cc 2008-11-13 20:19:09 +0000
@@ -67,6 +67,7 @@ static inline bool io_slave_killed(THD*
static inline bool sql_slave_killed(THD* thd,RELAY_LOG_INFO* rli);
static int count_relay_log_space(RELAY_LOG_INFO* rli);
static int init_slave_thread(THD* thd, SLAVE_THD_TYPE thd_type);
+static int init_recovery(MASTER_INFO* mi);
static int safe_connect(THD* thd, MYSQL* mysql, MASTER_INFO* mi);
static int safe_reconnect(THD* thd, MYSQL* mysql, MASTER_INFO* mi,
bool suppress_warnings);
@@ -174,6 +175,9 @@ int init_slave()
if (server_id && !master_host && active_mi->host[0])
master_host= active_mi->host;
+ if (init_recovery(active_mi))
+ goto err;
+
/* If server id is not set, start_slave_thread() will say it */
if (master_host && !opt_skip_slave_start)
@@ -197,6 +201,73 @@ err:
DBUG_RETURN(1);
}
+/*
+* Updates the master info based on the information stored in the relay info and
+* ignores relay logs previously retrieved by the IO thread starting fetching again
+* based on to the group_master_log_pos and group_master_log_name.
+*
+* There is no need for a mutex
+* as the caller (i.e. init_slave) already has one acquired.
+*
+* The recovery is done just after the database startup which means that
+* start slave and stop slave commands do not throw away any relay log
+* retrieved in the meantime.
+*
+* In the feature, we can improve this routine in order to avoid throwing
+* away logs that are safely stored in the disk. Eventually, the old
+* relay logs will be purged by the normal purge mechanism.
+*
+* Specifically,
+*
+* 1 - mi->master_log_pos <-- rli->group_master_log_pos
+* 2 - mi->master_log_name <-- rli->group_master_log_name
+* 3 - It moves the relay info to the new relay log file, by
+* rli->group_relay_log_pos <-- rli->group_relay_log_pos <-- BIN_LOG_HEADER_SIZE;
+* rli->group_relay_log_name, rli->group_relay_log_pos
+*
+* If there is an error, it returns (1), otherwise returns (0).
+*/
+static int init_recovery(MASTER_INFO* mi)
+{
+ const char* errmsg=0;
+ DBUG_ENTER("init_recovery");
+
+ RELAY_LOG_INFO* rli = &mi->rli;
+ if (relay_log_recovery && rli->group_master_log_name[0])
+ {
+ mi->master_log_pos = max(BIN_LOG_HEADER_SIZE,
+ rli->group_master_log_pos);
+ strmake(mi->master_log_name, rli->group_master_log_name,
+ sizeof(mi->master_log_name)-1);
+
+ strmake(rli->group_relay_log_name, rli->relay_log.get_log_fname(),
+ sizeof(rli->group_relay_log_name)-1);
+ strmake(rli->event_relay_log_name, rli->relay_log.get_log_fname(),
+ sizeof(mi->rli.event_relay_log_name)-1);
+
+ rli->group_relay_log_pos = rli->group_relay_log_pos = BIN_LOG_HEADER_SIZE;
+
+ if (init_relay_log_pos(rli,
+ rli->group_relay_log_name,
+ rli->group_relay_log_pos,
+ 0 /*no data lock*/,
+ &errmsg, 0))
+ DBUG_RETURN(1);
+
+ if (flush_master_info(mi, 0))
+ {
+ sql_print_error("Failed to flush master info file");
+ DBUG_RETURN(1);
+ }
+ if (flush_relay_log_info(rli))
+ {
+ sql_print_error("Failed to flush master info file");
+ DBUG_RETURN(1);
+ }
+ }
+
+ DBUG_RETURN(0);
+}
static void free_table_ent(TABLE_RULE_ENT* e)
{
