maria #2

  • By ibm-demo
  • Latest version (#2)
  • trusty
  • Stable
  • Edge

Description

MariaDB is an enhanced, drop-in replacement for MySQL. This charm takes a
binary tar.gz distribution of MariaDB and deploys it on an Ubuntu system.


Overview

MariaDB strives to be the logical choice for database
professionals looking for a robust, scalable, and reliable SQL server. To
accomplish this, the MariaDB Foundation works closely and cooperatively with
the larger community of users and developers in the true spirit of Free and
open source software, and release software in a manner that balances
predictability with reliability.

This charm deploys MariaDB using binary tar.gz files but uses the same charm
structure as the MySQL charm for the sake of compatability.

Usage

General Usage

To deploy a MySQL service:

juju deploy mariadb

NOTE: For quicker transfers of the MariaDB tar.gz and sha1sum files, create a
directory called "files" under the mariadb/ charm directory and download the
correct files for your CPU architechture ahead of time. Look in the
hooks/install file for what the current correct files are.

The files can be downloaded from: http://bb01.mariadb.net/10.0/

Once deployed, you can retrive the MySQL root user password by logging in to
the machine via juju ssh and reading the /var/lib/mysql/mysql.passwd file.
To log in as root MySQL User at the MySQL console you can issue the following:

juju ssh mariadb/0
mysql -u root -p$(sudo cat /var/lib/mysql/mysql.passwd)

Scale Out Usage

Replication

MySQL supports the ability to replicate databases to slave instances. This
allows you, for example, to load balance read queries across multiple slaves or
use a slave to perform backups, all whilst not impeding the master's
performance.

To deploy a slave:

# deploy second service
juju deploy mariadb mariadb-slave

# add master to slave relation
juju add-relation mariadb:master mariadb-slave:slave

Any changes to the master are reflected on the slave.

Any queries that modify the database(s) should be applied to the master only.
The slave should be treated strictly as read only.

You can add further slaves with:

juju add-unit mariadb-slave

Monitoring

This charm provides relations that support monitoring via either
Nagios or
Munin. Refer to the appropriate charm
for usage.

Configuration

You can tweak various options to optimize your MariaDB deployment:

  • max-connections - Maximum connections allowed to server or '-1' for default.

  • preferred-storage-engine - A comma separated list of storage engines to
    optimize for. First in the list is marked as default storage engine. 'InnoDB'
    or 'MyISAM' are acceptable values.

  • tuning-level - Specify 'safest', 'fast' or 'unsafe' to choose required
    transaction safety. This option determines the flush value for innodb commit
    and binary logs. Specify 'safest' for full ACID compliance. 'fast' relaxes the
    compliance for performance and 'unsafe' will remove most restrictions.

  • dataset-size - Memory allocation for all caches (InnoDB buffer pool, MyISAM
    key, query). Suffix value with 'K', 'M', 'G' or 'T' to indicate unit of
    kilobyte, megabyte, gigabyte or terabyte respectively. Suffix value with '%'
    to use percentage of machine's total memory.

  • query-cache-type - Specify 'ON', 'DEMAND' or 'OFF' to turn query cache on,
    selectively (dependent on queries) or off.

  • query-cache-size - Size of query cache (no. of bytes) or '-1' to use 20%
    of memory allocation.

Each of these can be applied by running:

juju set <service> <option>=<value>

For example:

juju set mariadb preferred-storage-engine=InnoDB
juju set mariadb dataset-size=50%
juju set mariadb query-cache-type=ON
juju set mariadb query-cache-size=-1

MariaDB Contact Information

Configuration

vip_iface
(string) Network Interface where to place the Virtual IP
eth0
ceph-osd-replication-count
(int) This value dictates the number of replicas ceph must make of any object it stores within the mysql rbd pool. Of course, this only applies if using Ceph as a backend store. Note that once the mysql rbd pool has been created, changing this value will not have any effect (although it can be changed in ceph by manually configuring your ceph cluster).
2
block-size
(int) Default block storage size to create when setting up MySQL block storage. This value should be specified in GB (e.g. 100 not 100GB).
5
tuning-level
(string) Valid values are 'safest', 'fast', and 'unsafe'. If set to safest, all settings are tuned to have maximum safety at the cost of performance. Fast will turn off most controls, but may lose data on crashes. unsafe will turn off all protections.
safest
rbd-name
(string) The name that will be used to create the Ceph's RBD image with. If the image name exists in Ceph, it will be re-used and the data will be overwritten.
mysql1
query-cache-size
(int) Override the computed version from dataset-size. Still works if query-cache-type is "OFF" since sessions can override the cache type setting on their own.
-1
query-cache-type
(string) Query cache is usually a good idea, but can hurt concurrency. Valid values are "OFF", "ON", or "DEMAND". http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html#sysvar_query_cache_type
OFF
vip
(string) Virtual IP to use to front mariadb in ha configuration
binlog-format
(string) If binlogging is enabled, this is the format that will be used. Ignored when tuning-level == fast.
MIXED
ha-mcastport
(int) Default multicast port number that will be used to communicate between HA Cluster nodes.
5411
max-connections
(int) Maximum connections to allow. -1 means use the server's compiled in default.
-1
preferred-storage-engine
(string) Tune the server for usage of this storage engine. Other possible value is MyISAM. Comma separated will cause settings to split resources evenly among given engines.
InnoDB
vip_cidr
(int) Netmask that will be used for the Virtual IP
24
dataset-size
(string) How much data do you want to keep in memory in the database. This will be used to tune settings in the database server appropriately. Any more specific settings will override these defaults though. This currently sets innodb_buffer_pool_size or key_cache_size depending on the setting in preferred-storage-engine. If query-cache-type is set to 'ON' or 'DEMAND' 20% of this is given to query-cache-size. Suffix this value with 'K','M','G', or 'T' to get the relevant kilo/mega/etc. bytes. If suffixed with %, one will get that percentage of RAM devoted to dataset and (if enabled) query cache.
80%
ha-bindiface
(string) Default network interface on which HA cluster will bind to communication with the other members of the HA Cluster.
eth0