#At file:///media/sdb2/hezx/work/mysql/bzrwork/semisync/5.1-rep-semisync/ based on revid:zhenxing.he@stripped
3117 He Zhenxing 2009-10-12
Backport BUG#47298 Semisync: always wait until timeout if no semi-sync slave available
Add an option to control whether the master should keep waiting
until timeout when it detected that there is no semi-sync slave
available.
The bool option 'rpl_semi_sync_master_wait_no_slave' is 1 by
defalt, and will keep waiting until timeout. When set to 0, the
master will switch to asynchronous replication immediately when
no semi-sync slave is available.
M mysql-test/suite/rpl/r/rpl_semi_sync.result
M mysql-test/suite/rpl/t/rpl_semi_sync.test
M plugin/semisync/semisync_master.cc
M plugin/semisync/semisync_master.h
M plugin/semisync/semisync_master_plugin.cc
M plugin/semisync/semisync_slave_plugin.cc
=== modified file 'mysql-test/suite/rpl/r/rpl_semi_sync.result'
--- a/mysql-test/suite/rpl/r/rpl_semi_sync.result 2009-10-12 13:03:04 +0000
+++ b/mysql-test/suite/rpl/r/rpl_semi_sync.result 2009-10-12 13:15:32 +0000
@@ -29,13 +29,13 @@ set global rpl_semi_sync_master_enabled
show variables like 'rpl_semi_sync_master_enabled';
Variable_name Value
rpl_semi_sync_master_enabled ON
-[ status of semi-sync on master should be OFF without any semi-sync slaves ]
+[ status of semi-sync on master should be ON even without any semi-sync slaves ]
show status like 'Rpl_semi_sync_master_clients';
Variable_name Value
Rpl_semi_sync_master_clients 0
show status like 'Rpl_semi_sync_master_status';
Variable_name Value
-Rpl_semi_sync_master_status OFF
+Rpl_semi_sync_master_status ON
show status like 'Rpl_semi_sync_master_yes_tx';
Variable_name Value
Rpl_semi_sync_master_yes_tx 0
@@ -210,7 +210,7 @@ include/stop_slave.inc
[ Semi-sync master status variables before FLUSH STATUS ]
SHOW STATUS LIKE 'Rpl_semi_sync_master_no_tx';
Variable_name Value
-Rpl_semi_sync_master_no_tx 3
+Rpl_semi_sync_master_no_tx 302
SHOW STATUS LIKE 'Rpl_semi_sync_master_yes_tx';
Variable_name Value
Rpl_semi_sync_master_yes_tx 302
@@ -355,7 +355,7 @@ Variable_name Value
Rpl_semi_sync_master_clients 0
show status like 'Rpl_semi_sync_master_status';
Variable_name Value
-Rpl_semi_sync_master_status OFF
+Rpl_semi_sync_master_status ON
set global rpl_semi_sync_master_enabled= 0;
[ on slave ]
SHOW VARIABLES LIKE 'rpl_semi_sync_slave_enabled';
@@ -364,17 +364,17 @@ rpl_semi_sync_slave_enabled ON
include/start_slave.inc
[ on master ]
insert into t1 values (8);
-[ master semi-sync clients should be 0, status should be OFF ]
+[ master semi-sync clients should be 1, status should be OFF ]
show status like 'Rpl_semi_sync_master_clients';
Variable_name Value
-Rpl_semi_sync_master_clients 0
+Rpl_semi_sync_master_clients 1
show status like 'Rpl_semi_sync_master_status';
Variable_name Value
Rpl_semi_sync_master_status OFF
[ on slave ]
show status like 'Rpl_semi_sync_slave_status';
Variable_name Value
-Rpl_semi_sync_slave_status OFF
+Rpl_semi_sync_slave_status ON
include/stop_slave.inc
[ on master ]
set sql_log_bin=0;
=== modified file 'mysql-test/suite/rpl/t/rpl_semi_sync.test'
--- a/mysql-test/suite/rpl/t/rpl_semi_sync.test 2009-10-12 13:03:04 +0000
+++ b/mysql-test/suite/rpl/t/rpl_semi_sync.test 2009-10-12 13:15:32 +0000
@@ -74,7 +74,7 @@ echo [ enable semi-sync on master ];
set global rpl_semi_sync_master_enabled = 1;
show variables like 'rpl_semi_sync_master_enabled';
-echo [ status of semi-sync on master should be OFF without any semi-sync slaves ];
+echo [ status of semi-sync on master should be ON even without any semi-sync slaves ];
show status like 'Rpl_semi_sync_master_clients';
show status like 'Rpl_semi_sync_master_status';
show status like 'Rpl_semi_sync_master_yes_tx';
@@ -497,7 +497,10 @@ source include/start_slave.inc;
connection master;
echo [ on master ];
insert into t1 values (8);
-echo [ master semi-sync clients should be 0, status should be OFF ];
+let $status_var= Rpl_semi_sync_master_clients;
+let $status_var_value= 1;
+source include/wait_for_status_var.inc;
+echo [ master semi-sync clients should be 1, status should be OFF ];
show status like 'Rpl_semi_sync_master_clients';
show status like 'Rpl_semi_sync_master_status';
sync_slave_with_master;
=== modified file 'plugin/semisync/semisync_master.cc'
--- a/plugin/semisync/semisync_master.cc 2009-10-12 13:03:04 +0000
+++ b/plugin/semisync/semisync_master.cc 2009-10-12 13:15:32 +0000
@@ -40,6 +40,7 @@ unsigned long long rpl_semi_sync_master_
unsigned long rpl_semi_sync_master_clients = 0;
unsigned long long rpl_semi_sync_master_net_wait_time = 0;
unsigned long long rpl_semi_sync_master_trx_wait_time = 0;
+char rpl_semi_sync_master_wait_no_slave = 1;
static int getWaitTime(const struct timeval& start_tv);
@@ -525,6 +526,14 @@ void ReplSemiSyncMaster::remove_slave()
{
lock();
rpl_semi_sync_master_clients--;
+
+ /* If user has chosen not to wait if no semi-sync slave available
+ and the last semi-sync slave exits, turn off semi-sync on master
+ immediately.
+ */
+ if (!rpl_semi_sync_master_wait_no_slave &&
+ rpl_semi_sync_master_clients == 0)
+ switch_off();
unlock();
}
@@ -812,7 +821,7 @@ int ReplSemiSyncMaster::commitTrx(const
trx_wait_binlog_pos));
/* Update the status counter. */
- if (is_on() && rpl_semi_sync_master_clients)
+ if (is_on())
rpl_semi_sync_master_yes_transactions++;
else
rpl_semi_sync_master_no_transactions++;
@@ -1078,7 +1087,7 @@ int ReplSemiSyncMaster::writeTranxInBinl
commit_file_name_inited_ = true;
}
- if (is_on() && rpl_semi_sync_master_clients)
+ if (is_on())
{
assert(active_tranxs_ != NULL);
if(active_tranxs_->insert_tranx_node(log_file_name, log_file_pos))
@@ -1153,7 +1162,7 @@ int ReplSemiSyncMaster::readSlaveReply(N
{
sql_print_error("Semi-sync master wait for reply "
"gettimeofday fail to get start time");
- timefunc_fails_++;
+ rpl_semi_sync_master_timefunc_fails++;
}
else
{
@@ -1164,12 +1173,12 @@ int ReplSemiSyncMaster::readSlaveReply(N
{
sql_print_error("Semi-sync master wait for reply "
"gettimeofday fail to get wait time.");
- timefunc_fails_++;
+ rpl_semi_sync_master_timefunc_fails++;
}
else
{
- total_net_wait_num_++;
- total_net_wait_time_ += wait_time;
+ rpl_semi_sync_master_net_wait_num++;
+ rpl_semi_sync_master_net_wait_time += wait_time;
}
}
}
@@ -1242,7 +1251,7 @@ void ReplSemiSyncMaster::setExportStats(
{
lock();
- rpl_semi_sync_master_status = state_ && rpl_semi_sync_master_clients;
+ rpl_semi_sync_master_status = state_;
rpl_semi_sync_master_avg_trx_wait_time=
((rpl_semi_sync_master_trx_wait_num) ?
(unsigned long)((double)rpl_semi_sync_master_trx_wait_time /
=== modified file 'plugin/semisync/semisync_master.h'
--- a/plugin/semisync/semisync_master.h 2009-10-12 13:03:04 +0000
+++ b/plugin/semisync/semisync_master.h 2009-10-12 13:15:32 +0000
@@ -363,4 +363,12 @@ extern unsigned long long rpl_semi_sync_
extern unsigned long long rpl_semi_sync_master_net_wait_time;
extern unsigned long long rpl_semi_sync_master_trx_wait_time;
+/*
+ This indicates whether we should keep waiting if no semi-sync slave
+ is available.
+ 0 : stop waiting if detected no avaialable semi-sync slave.
+ 1 (default) : keep waiting until timeout even no available semi-sync slave.
+*/
+extern char rpl_semi_sync_master_wait_no_slave;
+
#endif /* SEMISYNC_MASTER_H */
=== modified file 'plugin/semisync/semisync_master_plugin.cc'
--- a/plugin/semisync/semisync_master_plugin.cc 2009-10-12 13:03:04 +0000
+++ b/plugin/semisync/semisync_master_plugin.cc 2009-10-12 13:15:32 +0000
@@ -76,7 +76,7 @@ int repl_semi_binlog_dump_start(Binlog_t
/*
Let's assume this semi-sync slave has already received all
binlog events before the filename and position it requests.
- */
+ */
repl_semisync.reportReplyBinlog(param->server_id, log_file, log_pos);
}
sql_print_information("Start %s binlog_dump to slave (server_id: %d), pos(%s, %lu)",
@@ -176,6 +176,13 @@ static MYSQL_SYSVAR_ULONG(timeout, rpl_s
fix_rpl_semi_sync_master_timeout, // update
10000, 0, ~0L, 1);
+static MYSQL_SYSVAR_BOOL(wait_no_slave, rpl_semi_sync_master_wait_no_slave,
+ PLUGIN_VAR_OPCMDARG,
+ "Wait until timeout when no semi-synchronous replication slave available (enabled by default). ",
+ NULL, // check
+ NULL, // update
+ 1);
+
static MYSQL_SYSVAR_ULONG(trace_level, rpl_semi_sync_master_trace_level,
PLUGIN_VAR_OPCMDARG,
"The tracing level for semi-sync replication.",
@@ -186,6 +193,7 @@ static MYSQL_SYSVAR_ULONG(trace_level, r
static SYS_VAR* semi_sync_master_system_vars[]= {
MYSQL_SYSVAR(enabled),
MYSQL_SYSVAR(timeout),
+ MYSQL_SYSVAR(wait_no_slave),
MYSQL_SYSVAR(trace_level),
NULL,
};
=== modified file 'plugin/semisync/semisync_slave_plugin.cc'
--- a/plugin/semisync/semisync_slave_plugin.cc 2009-10-12 12:57:30 +0000
+++ b/plugin/semisync/semisync_slave_plugin.cc 2009-10-12 13:15:32 +0000
@@ -56,10 +56,11 @@ int repl_semi_slave_request_dump(Binlog_
}
row= mysql_fetch_row(res);
- if (!row || strcmp(row[1], "ON"))
+ if (!row)
{
- /* Master does not support or not configured semi-sync */
- sql_print_warning("Master server does not support or not configured semi-sync replication, fallback to asynchronous");
+ /* Master does not support semi-sync */
+ sql_print_warning("Master server does not support semi-sync, "
+ "fallback to asynchronous replication");
rpl_semi_sync_slave_status= 0;
return 0;
}
Attachment: [text/bzr-bundle] bzr/zhenxing.he@sun.com-20091012131532-r72zmehyavs2mn4r.bundle
| Thread |
|---|
| • bzr commit into mysql-5.1-rep-semisync branch (zhenxing.he:3117) Bug#47298 | He Zhenxing | 12 Oct |
