set --read_only on when --super_read_only is used as command line option

[Roel Van de Paar]

* Start PS mysqld with --super_read_only
* In CLI;

============================================================================
mysql> show global variables like 'super_read_only';show global variables like 'read_only';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| super_read_only | ON |
+-----------------+-------+
1 row in set (0.00 sec)

+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| read_only | OFF | <------------------------- (!)
+---------------+-------+
1 row in set (0.00 sec)

mysql> SET GLOBAL super_read_only=OFF;
Query OK, 0 rows affected (0.00 sec)

mysql> show global variables like 'super_read_only';show global variables like 'read_only';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| super_read_only | OFF |
+-----------------+-------+
1 row in set (0.00 sec)

+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| read_only | OFF |
+---------------+-------+
1 row in set (0.00 sec)

mysql> SET GLOBAL super_read_only=ON;
Query OK, 0 rows affected (0.00 sec)

mysql> show global variables like 'super_read_only';show global variables like 'read_only';
+-----------------+-------+
| Variable_name | Value |
+-----------------+-------+
| super_read_only | ON |
+-----------------+-------+
1 row in set (0.00 sec)

+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| read_only | ON |
+---------------+-------+
1 row in set (0.00 sec)
============================================================================

Note (!) marker. Either (imho best) the read_only should be ON when --super_read_only was used as a startup paramenter, or the manual should be improved to make it clear that if --super_read_only is used as a command line option, that it does not automatically enable --read_only.

Manual is here;
http://www.percona.com/doc/percona-server/5.6/management/super_read_only.html

[Laurynas Biveinis (laurynas-biveinis)]

Must be an upstream bug, please test WebScaleSQL and report it there (https://github.com/webscalesql/webscalesql-5.6/issues).

This needs fixing as suggested, not documenting the current behavior.

[Roel Van de Paar (roel11)]

Compiling webscalesql is failing. Even after installing readline-devel (it's needed), I get this;

[ 96%] Building CXX object client/CMakeFiles/mysql.dir/mysql.cc.o
/bzr/webscalesql-5.6-webscalesql-5.6.21/client/mysql.cc:1102:16: error: redefinition of 'struct _hist_entry'
 typedef struct _hist_entry {
                ^
In file included from /bzr/webscalesql-5.6-webscalesql-5.6.21/client/mysql.cc:101:0:
/usr/include/readline/history.h:46:16: error: previous definition of 'struct _hist_entry'
 typedef struct _hist_entry {
                ^
/bzr/webscalesql-5.6-webscalesql-5.6.21/client/mysql.cc:1105:13: error: invalid type in declaration before ';' token
 } HIST_ENTRY;
             ^
/bzr/webscalesql-5.6-webscalesql-5.6.21/client/mysql.cc:1105:13: error: conflicting declaration 'typedef int HIST_ENTRY'
In file included from /bzr/webscalesql-5.6-webscalesql-5.6.21/client/mysql.cc:101:0:
/usr/include/readline/history.h:50:3: error: 'HIST_ENTRY' has a previous declaration as 'typedef struct _hist_entry HIST_ENTRY'
 } HIST_ENTRY;
   ^
make[2]: *** [client/CMakeFiles/mysql.dir/mysql.cc.o] Error 1
make[1]: *** [client/CMakeFiles/mysql.dir/all] Error 2
make: *** [all] Error 2

Any ideas?

[Roel Van de Paar (roel11)]

If no ideas, I'll log upstream bug, which effectively halts progress on QA as there is another bug for which I need a compiled version also. Thanks

[Gary (pento)]

I was able to reproduce the behaviour in comment 5, compiling WebScaleSQL 5.6.23 on Ubuntu 14.04.1 LTS.

I fixed it by installing the libedit-dev package.

[Roel Van de Paar (roel11)]

http://www.psce.com/blog/2015/02/04/webscalesql-rpms-available-at-psce-repository/

[Laurynas Biveinis (laurynas-biveinis)]

This is fixed by Facebook patch by https://github.com/facebook/mysql-5.6/commit/c70dd2f4c7897734109d62f46f22751cddbb5d9a

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-1579