# Ack All (/sdks/ruby/how-to/queues/ack-all)



## Overview [#overview]

`ack_all_queue_messages` acknowledges **every pending message on a channel in a single broker-side call**, without receiving them first. Reach for it when you want to *drain* a queue rather than *process* it — clearing a backlog of stale work after a bad deploy, resetting a channel between test runs, or discarding messages that are no longer relevant — where pulling and acking each message individually would be slow and wasteful.

Because it settles the whole channel at once, it is far cheaper than a receive-then-ack loop: the broker confirms all in-flight messages atomically and reports how many were affected, using `wait_timeout_seconds` to bound how long it waits for in-flight transactions to settle before counting.

**Gotchas:** this is a blunt, irreversible instrument — it acknowledges *all* currently-pending messages, not a selected subset, so anything unprocessed is discarded, not redelivered. A busy channel may need a larger `wait_timeout_seconds` to catch messages still landing. For routine, per-message cleanup use ordinary acks, an expiration policy, or a [dead-letter policy](/sdks/ruby/how-to/queues/dead-letter-policy) instead — save ack-all for deliberate, wholesale purges.

## Prerequisites [#prerequisites]

* KubeMQ server running on `localhost:50000`
* Ruby SDK installed (`gem install kubemq`)

## Code [#code]

```ruby title="main.rb"
require 'kubemq'

address = ENV.fetch('KUBEMQ_ADDRESS', 'localhost:50000')
channel = 'ruby-queues.ack-all'

begin
  client = KubeMQ::QueuesClient.new(address: address, client_id: 'qs-ackall-example')
  puts "Connected to #{address}"

  5.times do |i|
    msg = KubeMQ::Queues::QueueMessage.new(channel: channel, metadata: "item-#{i}", body: "data-#{i}")
    client.send_queue_message(msg)
  end
  puts 'Sent 5 messages'

  affected = client.ack_all_queue_messages(channel: channel, wait_timeout_seconds: 5)
  puts "Acknowledged #{affected} messages"

  remaining = client.receive_queue_messages(channel: channel, max_messages: 10, wait_timeout_seconds: 2)
  puts "Remaining messages: #{remaining.size}"
rescue KubeMQ::Error => e
  puts "KubeMQ error: #{e.message}"
ensure
  client&.close
  puts 'Done'
end
```

## How It Works [#how-it-works]

* `ack_all_queue_messages` removes all pending messages from the queue in a single operation.
* Returns the number of messages that were acknowledged.
* Review timeouts, channel names, and client IDs before running against shared environments.

## Related [#related]

* [Pattern overview](/learn/queues/getting-started)
* [Ruby SDK Reference](/sdks/ruby/reference)
* [Ack/Reject](/sdks/ruby/how-to/queues/ack-reject)
* [Ack Range](/sdks/ruby/how-to/queues/ack-range)