gitlab-org--gitlab-foss/lib/gitlab/metrics/influx_db.rb
2019-03-13 13:42:43 +00:00

183 lines
5.7 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Metrics
module InfluxDb
extend ActiveSupport::Concern
include Gitlab::Metrics::Methods
EXECUTION_MEASUREMENT_BUCKETS = [0.001, 0.01, 0.1, 1].freeze
MUTEX = Mutex.new
private_constant :MUTEX
class_methods do
def influx_metrics_enabled?
settings[:enabled] || false
end
# Prometheus histogram buckets used for arbitrary code measurements
def settings
@settings ||= begin
current_settings = Gitlab::CurrentSettings.current_application_settings
{
enabled: current_settings[:metrics_enabled],
pool_size: current_settings[:metrics_pool_size],
timeout: current_settings[:metrics_timeout],
method_call_threshold: current_settings[:metrics_method_call_threshold],
host: current_settings[:metrics_host],
port: current_settings[:metrics_port],
sample_interval: current_settings[:metrics_sample_interval] || 15,
packet_size: current_settings[:metrics_packet_size] || 1
}
end
end
def mri?
RUBY_ENGINE == 'ruby'
end
def method_call_threshold
# This is memoized since this method is called for every instrumented
# method. Loading data from an external cache on every method call slows
# things down too much.
# in milliseconds
@method_call_threshold ||= settings[:method_call_threshold]
end
def submit_metrics(metrics)
prepared = prepare_metrics(metrics)
pool&.with do |connection|
prepared.each_slice(settings[:packet_size]) do |slice|
connection.write_points(slice)
rescue StandardError
end
end
rescue Errno::EADDRNOTAVAIL, SocketError => ex
Gitlab::EnvironmentLogger.error('Cannot resolve InfluxDB address. GitLab Performance Monitoring will not work.')
Gitlab::EnvironmentLogger.error(ex)
end
def prepare_metrics(metrics)
metrics.map do |hash|
new_hash = hash.symbolize_keys
new_hash[:tags].each do |key, value|
if value.blank?
new_hash[:tags].delete(key)
else
new_hash[:tags][key] = escape_value(value)
end
end
new_hash
end
end
def escape_value(value)
value.to_s.gsub('=', '\\=')
end
# Measures the execution time of a block.
#
# Example:
#
# Gitlab::Metrics.measure(:find_by_username_duration) do
# UserFinder.new(some_username).find_by_username
# end
#
# name - The name of the field to store the execution time in.
#
# Returns the value yielded by the supplied block.
def measure(name)
trans = current_transaction
return yield unless trans
real_start = Time.now.to_f
cpu_start = System.cpu_time
retval = yield
cpu_stop = System.cpu_time
real_stop = Time.now.to_f
real_time = (real_stop - real_start)
cpu_time = cpu_stop - cpu_start
real_duration_seconds = fetch_histogram("gitlab_#{name}_real_duration_seconds".to_sym) do
docstring "Measure #{name}"
base_labels Transaction::BASE_LABELS
buckets EXECUTION_MEASUREMENT_BUCKETS
end
real_duration_seconds.observe(trans.labels, real_time)
cpu_duration_seconds = fetch_histogram("gitlab_#{name}_cpu_duration_seconds".to_sym) do
docstring "Measure #{name}"
base_labels Transaction::BASE_LABELS
buckets EXECUTION_MEASUREMENT_BUCKETS
with_feature "prometheus_metrics_measure_#{name}_cpu_duration"
end
cpu_duration_seconds.observe(trans.labels, cpu_time)
# InfluxDB stores the _real_time and _cpu_time time values as milliseconds
trans.increment("#{name}_real_time", real_time.in_milliseconds, false)
trans.increment("#{name}_cpu_time", cpu_time.in_milliseconds, false)
trans.increment("#{name}_call_count", 1, false)
retval
end
# Sets the action of the current transaction (if any)
#
# action - The name of the action.
def action=(action)
trans = current_transaction
trans&.action = action
end
# Tracks an event.
#
# See `Gitlab::Metrics::Transaction#add_event` for more details.
def add_event(*args)
current_transaction&.add_event(*args)
end
# Returns the prefix to use for the name of a series.
def series_prefix
@series_prefix ||= Sidekiq.server? ? 'sidekiq_' : 'rails_'
end
# Allow access from other metrics related middlewares
def current_transaction
Transaction.current
end
# When enabled this should be set before being used as the usual pattern
# "@foo ||= bar" is _not_ thread-safe.
def pool
if influx_metrics_enabled?
if @pool.nil?
MUTEX.synchronize do
@pool ||= ConnectionPool.new(size: settings[:pool_size], timeout: settings[:timeout]) do
host = settings[:host]
port = settings[:port]
InfluxDB::Client
.new(udp: { host: host, port: port })
end
end
end
@pool
end
end
end
end
end
end