def write_multi(hash, options = {})
      options = merged_options(options)

      invoke(:write_multi, hash.keys) do |store|
        store.multi do
          hash.each { |key, value| write_entity(key, value, store, options) }
        end
      end
    end
def write_multi(hash, options = {})
      options = merged_options(options)

      invoke(:write_multi, hash.keys) do |store|
        store.multi do
          hash.each { |key, value| write_entity(key, value, store, options) }
        end
      end
    end
Write multiple key value pairs simultaneously. This is an atomic
 operation that will always succeed and will overwrite existing
 values.

 This is a non-standard, but useful, cache method.

 @param [Hash] hash Key value hash to write
 @param [Hash] options Optional overrides

 @example

   cache.write_multi({ 'a' => 1, 'b' => 2 }) # => true