NAME¶
DBIx::Class::Storage::DBI::Replicated::Balancer::Random - A 'random' Balancer
SYNOPSIS¶
This class is used internally by DBIx::Class::Storage::DBI::Replicated. You
shouldn't need to create instances of this class.
DESCRIPTION¶
Given a pool (DBIx::Class::Storage::DBI::Replicated::Pool) of replicated
database's (DBIx::Class::Storage::DBI::Replicated::Replicant), defines a
method by which query load can be spread out across each replicant in the
pool.
This Balancer uses List::Util keyword 'shuffle' to randomly pick an active
replicant from the associated pool. This may or may not be random enough for
you, patches welcome.
ATTRIBUTES¶
This class defines the following attributes.
master_read_weight¶
A number greater than 0 that specifies what weight to give the master when
choosing which backend to execute a read query on. A value of 0, which is the
default, does no reads from master, while a value of 1 gives it the same
priority as any single replicant.
For example: if you have 2 replicants, and a "master_read_weight" of
0.5, the chance of reading from master will be "20%".
You can set it to a value higher than 1, making master have higher weight than
any single replicant, if for example you have a very powerful master.
METHODS¶
This class defines the following methods.
next_storage¶
Returns an active replicant at random. Please note that due to the nature of the
word 'random' this means it's possible for a particular active replicant to be
requested several times in a row.
FURTHER QUESTIONS?¶
Check the list of additional DBIC resources.
COPYRIGHT AND LICENSE¶
This module is free software copyright by the DBIx::Class (DBIC) authors. You
can redistribute it and/or modify it under the same terms as the DBIx::Class
library.