Torsten Raudssus > DBIx-Class > DBIx::Class::Storage::DBI::Replicated::Balancer::Random

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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.

AUTHOR ^

John Napiorkowski <john.napiorkowski@takkle.com>

LICENSE ^

You may distribute this code under the same terms as Perl itself.

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