Delete large Redis sets with Ruby and Sidekiq

gistfile1.rb

$redis = Redis.new

class SafeSetDelete
  include Sidekiq::Worker

  BATCH_SIZE = 100

  # Rename the key and queue for deletion
  def self.delete(key)
    newkey = "gc:sets:#{$redis.incr("gc:index")}"
    $redis.rename(key, newkey)
    self.perform_async(newkey)
  end

  # Delete members from the set in batches
  def self.perform(key)
    cursor = "0"
    loop do
      cursor, members = $redis.sscan(key, cursor, count: BATCH_SIZE)
      $redis.srem(key, members) if members.size > 0
      break if cursor == "0"
    end
  end
end

# Example:
#
#   SafeSetDelete.delete("my.large.set")