ADMIN

MySQL Forks and Patches
Features
In non-traditional mode, MySQL ignores
the default use and still runs
the queries; in traditional mode, the
query quits with an error. Thus, it is
a good idea in many cases to change
the line to sql‐mode=NO_ENGINE_SUB‐
STITUTION and then restart the
server. This problem is not specific
to MariaDB, simply a very restrictive
configuration in line with the MySQL
standard. Additionally, it makes sense
to check whether programs compiled
against Libmysqlclient-dev need to be
recompiled against the current Libmariadbclient-device.
In a Rails environment,
this will affect Mysql-Gem.
Besides the benefits of the InnoDB
plugin described thus far, XtraDB also
offers a considerable performance
boost, as a variety of benchmarks
with various setups proves [10]. Numerous
additional functions make life
easier for developers and administrators
– and don’t forget the ability to
write out the InnoDB buffer to disk.
If you do need to restart the MySQL
or MariaDB server, the InnoDB engine
loses its valuable buffer pool in RAM.
Depending on your configuration and
the application, the pool can be several
gigabytes and might be filled in
the course of hours. Storing the buffer
pool before quitting and loading it
again after restarting will save valuable
warmup time, which you would
notice as slow response on the part of
the database server. Listing 5 shows
the commands and returns for storing
and loading the buffer pool.
Drizzle
At this point, I’ll take a quick look
at a new development, Drizzle [11].
According to the project, the fork is a
return to the original MySQL values:
simplicity, reliability, and performance.
Drizzle was originally based
on the code of the not-yet-released
MySQL 6.0 and mainly pursues the
goals of removing unnecessary functions
and reducing complexity.
The developers really have been radical
in the features they eradicated: E
Listing 5: Storing and Loading the Buffer Pool
// storing the buffer pool
MariaDB [(none)]> select * from
information_schema.XTRADB_ADMIN_COMMAND
/*!XTRA_LRU_DUMP*/;
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
| result_message |
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
| XTRA_LRU_DUMP was succeeded. |
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
// loading buffer pool and
MariaDB [(none)]> select * from information_schema.
XTRADB_ADMIN_COMMAND /*!XTRA_LRU_RESTORE*/;
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
| result_message |
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
| XTRA_LRU_RESTORE was succeeded. |
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+
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