Sidekiq is a simple and efficient background processor for Ruby. It's also the processor we use to process jobs in AppSignal.

Support for Sidekiq was added in AppSignal Ruby gem version 0.8.

Job naming

Job names are automatically detected based on the Sidekiq worker class name and are suffixed with the perform method name, resulting in something like: MyWorker#perform.

If your app is using the Sidekiq delayed extensions, please upgrade to AppSignal Ruby gem version 2.4.1 or higher as support for this extension was improved.

You can recognize events from Sidekiq with the name perform_job.sidekiq in the event timeline on the performance incident detail page.


Using with Rails

The AppSignal Ruby gem automatically inserts a listener into the Sidekiq server middleware stack if the Sidekiq module is present if you use Rails. No further action is required.

Using with Active Job

The Sidekiq integration is compatible with Active Job.

Upgrade to version 2.11.0 of the Ruby gem or newer for improved support.

Using standalone

If you use Sidekiq without Rails some additional setup is required. Add this snippet to your Sidekiq config with the right environment and name:

require 'appsignal'
Sidekiq.on(:startup) do
  # Load config
  Appsignal.config =
    ENV['APPSIGNAL_APP_ENV'],        # Set environment here
    :name   => 'Sidekiq standalone', # Set app name here
  # Start AppSignal
  # Initialize the logger
Sidekiq.on(:shutdown) do
  # Stop the agent
  Appsignal.stop('Sidekiq shutdown')

Internal Sidekiq errors

ℹ️ This type of error reporting was added in AppSignal for Ruby gem version 3.0.

When Sidekiq encounters a problem before or after a job has been processed, such as parsing JSON from Redis, it will raise an error. This error is reported under the SidekiqInternal action on the background namespace, as the context of the job is unknown at the time the error occurs.


The Sidekiq integration will report the following metrics for every processed job.

  • sidekiq_queue_job_count - counter
    • Counter is incremented for every processed job.
    • Tags:
      • Tag queue: Name of the queue, e.g. default or critical. Will fall back on unknown if it cannot be detected.
      • Tag status:
        • processed - every job that's been processed, includes failed jobs.
        • failed - every job that's failed while being processed.

Minutely probe

Note: Requires Redis gem 3.3.5 or higher.

Note: AppSignal Ruby gem 2.9.5 is recommended.

Since AppSignal Ruby gem 2.9.0 and up a minutely probe is activated by default. Once we detect these metrics we'll add a magic dashboard to your apps.

This probe will report the following metrics grouped by hostname tag:

  • sidekiq_worker_count - gauge
    • The total number of works active for the Sidekiq processes.
  • sidekiq_process_count - gauge
    • The Sidekiq processes that are active.
  • sidekiq_connection_count - gauge
    • How many connections were open to the Redis database.
  • sidekiq_memory_usage - gauge
    • The Virtual Memory Size memory usage of Redis.
  • sidekiq_memory_usage_rss - gauge
    • The Resident Set Size memory usage of Redis.
  • sidekiq_job_count - gauge
    • Tag status:
      • processed: all processed jobs in this minute, this includes failed jobs.
      • failed: number of failed jobs in this minute.
      • retry_queue: number of jobs that were in the retry queue in this minute. These jobs have failed before and were scheduled by Sidekiq to be retried.
      • died: number of jobs that died in this minute. They have been retried the maximum amount of times and Sidekiq will stop retrying them.
      • scheduled: number of jobs that were in the "scheduled" queue. They have not been processed yet.
      • enqueued: number of jobs that were in the queue to be processed.
  • sidekiq_queue_length - gauge
    • The queue length at the time of measurement.
    • Tag queue: Name of the queue, e.g. default or critical.
  • sidekiq_queue_latency - gauge
    • The latency the queue experienced at the time of measurement. Sidekiq calculates this by subtracting the time the last job was enqueued from the time of measurement. This value is reported as milliseconds.
    • Note: Please upgrade to AppSignal Ruby gem 2.9.4 for accurate reporting for this metric.
    • Tag queue: Name of the queue, e.g. default or critical.


This probe does its best to detect the hostname of the Redis instance your Sidekiq instance uses to store its queues. If the detection is not accurate (let us know), it's possible to customize the hostname config by overriding the default Sidekiq probe.

First you'll need to override the default sidekiq probe by registering a new probe with the same name (:sidekiq). This probe will need a configuration hash including the :hostname key, with the new hostname value. By specifying the :hostname config option the Sidekiq minutely probe, the metrics will be tagged with the given hostname value. The :hostname config option value is not used to establish a Redis or Sidekiq connection.

An example is listed below.

# config/initializers/appsignal.rb or a file that's loaded on boot
# Ruby gem 2.11.0 and newer
  :sidekiq, # Use the same key as the default Sidekiq probe to override it => "my_sidekiq_hostname")
# Ruby gem 2.10.x and older
  :sidekiq, # Use the same key as the default Sidekiq probe to override it => "my_sidekiq_hostname")

In version 2.11.0 of the Ruby gem the SidekiqProbe constant was moved to its own module. Upon calling the constant a warning will be printed and logged. Update to the new constant name Appsignal::Probes::SidekiqProbe to remove the warning.

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