redis_and_queues.rb

redis_and_queues.rb

r = Redis.new(url: ENV['REDIS_URL'])

def fetch_all_keys(r, batch: 10_000, match: nil)
  cursor = '0'
  all_keys = []
  loop do
    cursor, k = r.scan(cursor, count: batch, match: match)
    all_keys += k
    break if cursor == '0'
  end
  all_keys
end


def delete_these_keys(r, all_keys, batch_size: 500)
  all_keys.each_slice(batch_size) { |x| r.del(x) }
end


def hist_groups(gfn, dataset)
  hist = {}
  dataset.each { |e| g = gfn.call(e); hist[g] = hist[g].to_i + 1 }
  hist.sort_by { |k, v| -v }
end

def hist_groups_vals(gfn, dataset)
  hist = {}
  dataset.each { |e| g = gfn.call(e); hist[g] = Array(hist[g]) + [e] }
  hist.sort_by { |k, v| -v.length }
end


def bytekb(v)
  v < 1024 ? v : (v < 1048576 ? ("%.2fkb" % [v/1024.0]) : (v < 1073741824 ? ("%.2fmb" % [v/1048576.0]) : ("%.2fgb" % [v/ 1073741824])))
end

def print_keys_by_size(r, only: nil, batch: 10_000)
  all_keys = fetch_all_keys(r, batch: batch)
  us = all_keys.map { |k| [k, r.call('memory', 'usage', k)] }.select { |_, v| v }.sort_by { |_, v| -v }.map { |a, v| [a, bytekb(v)] }
  us = us[0...only] if only
  us.each { |k, v| puts("#{v} -> #{k}") }
  nil
end