gitlab-org--gitlab-foss/lib/gitlab/middleware/rails_queue_duration.rb

33 lines
1.1 KiB
Ruby

# This Rack middleware is intended to measure the latency between
# gitlab-workhorse forwarding a request to the Rails application and the
# time this middleware is reached.
module Gitlab
module Middleware
class RailsQueueDuration
def self.metric_rails_queue_duration_seconds
@metric_rails_queue_duration_seconds ||= Gitlab::Metrics.histogram(
:gitlab_rails_queue_duration_seconds,
Gitlab::Metrics::Transaction::BASE_LABELS
)
end
def initialize(app)
@app = app
end
def call(env)
trans = Gitlab::Metrics.current_transaction
proxy_start = env['HTTP_GITLAB_WORKHORSE_PROXY_START'].presence
if trans && proxy_start
# Time in milliseconds since gitlab-workhorse started the request
duration = Time.now.to_f * 1_000 - proxy_start.to_f / 1_000_000
trans.set(:rails_queue_duration, duration)
self.class.metric_rails_queue_duration_seconds.observe(trans.labels, duration / 1_000)
end
@app.call(env)
end
end
end
end