revision-id: 096722b61ebe66ffe510156d358d4ddbeb53241a (mariadb-10.2.25-35-g096722b61eb) parent(s): 41f6e68878df46dd7abc8a98234f58a1fa030592 author: Sujatha committer: Sujatha timestamp: 2019-07-11 12:33:32 +0530 message: MDEV-11154: Write_on_release_cache(log_event.cc) function will not write "COMMIT", if use "mysqlbinlog ... | mysql ..." Problem: ======= Executing command, "mysqlbinlog --read-from-remote-server --host='xx.xx.xx.xx' --port=3306 --user=xxx --password=xxx --database=mysql --to-last-log mysql-bin.000001 --start-position=1098699 --stop-never |mysql -uxxx -pxxx", we found that last data read from remote couldn't commit. Analysis: ======== The purpose of 'Write_on_release_cache' is that the contents of the Cache will automatically be written to a dedicated result file on destruction. Flush operation on the result file is controlled by a flag 'FLUSH_F'. Events which require force flush upon their destruction will have to enable this 'Write_on_release_cache::FLUSH_F'. At present the 'FLUSH_F' flag is defined as an enum as shown below. enum flag { FLUSH_F }; Since 'FLUSH_F' is the first member without initialization it get the default value '0'. Because of this the following flush condition never succeeds. if (m_flags & FLUSH_F) fflush(m_file); At present the file gets flushed only during my_fclose(result_file) operation. When continuous streaming is enabled through --stop-never option it never gets flushed and hence events are not replicated. Fix: === Initialize the enum value to non zero value. FLUSH_F is effective when event cache is copied to file. From 10.2 onwards the event cache can also be copied to a string. This string is appended to result_file at the end of processing the event. An additional flush needs to be done after the event is written to the result_file. --- client/mysqlbinlog.cc | 1 + .../binlog/r/binlog_mysqlbinlog_stop_never.result | 16 ++++++ .../binlog/t/binlog_mysqlbinlog_stop_never.test | 66 ++++++++++++++++++++++ sql/log_event.cc | 2 +- 4 files changed, 84 insertions(+), 1 deletion(-) diff --git a/client/mysqlbinlog.cc b/client/mysqlbinlog.cc index 1516e08284b..acccf0a3411 100644 --- a/client/mysqlbinlog.cc +++ b/client/mysqlbinlog.cc @@ -1534,6 +1534,7 @@ Exit_status process_event(PRINT_EVENT_INFO *print_event_info, Log_event *ev, { my_fwrite(result_file, (const uchar *) tmp_str.str, tmp_str.length, MYF(MY_NABP)); + fflush(result_file); my_free(tmp_str.str); } } diff --git a/mysql-test/suite/binlog/r/binlog_mysqlbinlog_stop_never.result b/mysql-test/suite/binlog/r/binlog_mysqlbinlog_stop_never.result new file mode 100644 index 00000000000..e94f17b9489 --- /dev/null +++ b/mysql-test/suite/binlog/r/binlog_mysqlbinlog_stop_never.result @@ -0,0 +1,16 @@ +RESET MASTER; +include/stop_dump_threads.inc +# Step-1: Execute some dummy statements. +CREATE TABLE t1(i int); +INSERT INTO t1 values (1); +# Step-2: Disable binary log temporarily and drop the table 't1'. +set @@SESSION.SQL_LOG_BIN = 0; +DROP TABLE t1; +set @@SESSION.SQL_LOG_BIN = 1; +# Step-3: Execute MYSQL_BINLOG with --stop-never and source it to mysql client. +# Step-4: Wait till dump thread transfer is completed. +# Step-5: Check that the data is there. +# Step-6: Cleanup +# kill the dump thread serving the mysqlbinlog --stop-never process +include/stop_dump_threads.inc +DROP TABLE t1; diff --git a/mysql-test/suite/binlog/t/binlog_mysqlbinlog_stop_never.test b/mysql-test/suite/binlog/t/binlog_mysqlbinlog_stop_never.test new file mode 100644 index 00000000000..d73e453ce96 --- /dev/null +++ b/mysql-test/suite/binlog/t/binlog_mysqlbinlog_stop_never.test @@ -0,0 +1,66 @@ +# ==== Purpose ==== +# +# Test verifies that continuous streaming of binary log content using the +# "mysqlbinlog --stop-never" option and sourcing it to mysql client works +# fine. +# +# ==== Implementation ==== +# +# Steps: +# 1 - Create a table on a server on which binary log is enabled and insert +# a row. +# 2 - Disable the binary log on the server and drop the table. +# 3 - Capture the binary log output using "mysqlbinlog --stop_never" option +# and source it to mysql client. +# 4 - Query the PROCESSLIST table to ensure that the dump thread which is +# serving "stop_never" option has read entire binlog. +# 5 - Verify that the table is populated on the server. +# 6 - Cleanup. +# +# ==== References ==== +# +# MDEV-11154: Write_on_release_cache(log_event.cc) function will not write +# "COMMIT", if use "mysqlbinlog ... | mysql ..." + +--source include/not_windows.inc + +# Test is not specific to any binlog format. Hence Running only for 'row'. +--source include/have_binlog_format_row.inc + +# binlog file name is needed in the test. To use master-bin.000001, +# RESET MASTER is needed. +RESET MASTER; +# kill the dump threads if there any dump threads (may be from previous test) +--source include/stop_dump_threads.inc + +--echo # Step-1: Execute some dummy statements. +CREATE TABLE t1(i int); +INSERT INTO t1 values (1); + +--echo # Step-2: Disable binary log temporarily and drop the table 't1'. +set @@SESSION.SQL_LOG_BIN = 0; +DROP TABLE t1; +set @@SESSION.SQL_LOG_BIN = 1; + +--echo # Step-3: Execute MYSQL_BINLOG with --stop-never and source it to mysql client. +--write_file $MYSQL_TMP_DIR/mysqlbinlog_stop_never.sh +(`$MYSQL_BINLOG --read-from-remote-server --stop-never --user=root --host=127.0.0.1 --port=$MASTER_MYPORT master-bin.000001 | $MYSQL --user=root --protocol=tcp --host=127.0.0.1 --port=$MASTER_MYPORT`) < /dev/null > /dev/null 2>&1 & +EOF +--exec /bin/bash $MYSQL_TMP_DIR/mysqlbinlog_stop_never.sh + +--echo # Step-4: Wait till dump thread transfer is completed. +let $wait_condition= SELECT id from information_schema.processlist where processlist.command like '%Binlog%' and state like '%Master has sent%'; +--source include/wait_condition.inc + +--echo # Step-5: Check that the data is there. +let $count= 1; +let $table= test.t1; +source include/wait_until_rows_count.inc; + +--echo # Step-6: Cleanup +--echo # kill the dump thread serving the mysqlbinlog --stop-never process +--source include/stop_dump_threads.inc + +DROP TABLE t1; +--remove_file $MYSQL_TMP_DIR/mysqlbinlog_stop_never.sh + diff --git a/sql/log_event.cc b/sql/log_event.cc index 01f31aceff7..0e0d69b515c 100644 --- a/sql/log_event.cc +++ b/sql/log_event.cc @@ -296,7 +296,7 @@ class Write_on_release_cache public: enum flag { - FLUSH_F + FLUSH_F= 1 }; typedef unsigned short flag_set;