class NewRelic::Agent::StatsEngine

This class handles all the statistics gathering for the agent

Attributes

metric_rules[RW]

Public Class Methods

new() click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 15
def initialize
  @stats_lock = Mutex.new
  @stats_hash = StatsHash.new
  @metric_rules = RulesEngine.new
end

Public Instance Methods

apply_rules_to_metric_data(rules_engine, stats_hash) click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 160
def apply_rules_to_metric_data(rules_engine, stats_hash)
  renamed_stats = NewRelic::Agent::StatsHash.new(stats_hash.started_at)
  stats_hash.each do |spec, stats|
    new_name = rules_engine.rename(spec.name)
    unless new_name.nil?
      new_spec = NewRelic::MetricSpec.new(new_name, spec.scope)
      renamed_stats[new_spec].merge!(stats)
    end
  end
  renamed_stats
end
clear_stats() click to toggle source

For use by test code only.

# File lib/new_relic/agent/stats_engine.rb, line 187
def clear_stats
  reset!
  NewRelic::Agent::TransactionTimeAggregator.reset!
end
coerce_to_metric_spec_array(metric_names_or_specs, scope) click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 172
def coerce_to_metric_spec_array(metric_names_or_specs, scope)
  specs = []
  Array(metric_names_or_specs).map do |name_or_spec|
    case name_or_spec
    when String
      specs << NewRelic::MetricSpec.new(name_or_spec)
      specs << NewRelic::MetricSpec.new(name_or_spec, scope) if scope
    when NewRelic::MetricSpec
      specs << name_or_spec
    end
  end
  specs
end
harvest!() click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 152
def harvest!
  now = Process.clock_gettime(Process::CLOCK_REALTIME)
  snapshot = reset!
  snapshot = apply_rules_to_metric_data(@metric_rules, snapshot)
  snapshot.harvested_at = now
  snapshot
end
merge!(other_stats_hash) click to toggle source

merge data from previous harvests into this stats engine

# File lib/new_relic/agent/stats_engine.rb, line 139
def merge!(other_stats_hash)
  with_stats_lock do
    @stats_hash.merge!(other_stats_hash)
    @stats_hash
  end
end
merge_transaction_metrics!(txn_metrics, scope) click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 146
def merge_transaction_metrics!(txn_metrics, scope)
  with_stats_lock do
    @stats_hash.merge_transaction_metrics!(txn_metrics, scope)
  end
end
record_scoped_and_unscoped_metrics(state, scoped_metric, summary_metrics = nil, value = nil, aux = nil, &blk) click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 104
def record_scoped_and_unscoped_metrics(state, scoped_metric, summary_metrics = nil, value = nil, aux = nil, &blk)
  txn = state.current_transaction
  if txn
    txn.metrics.record_scoped_and_unscoped(scoped_metric, value, aux, &blk)
    if summary_metrics
      txn.metrics.record_unscoped(summary_metrics, value, aux, &blk)
    end
  else
    specs = coerce_to_metric_spec_array(scoped_metric, nil)
    if summary_metrics
      specs.concat(coerce_to_metric_spec_array(summary_metrics, nil))
    end
    with_stats_lock do
      @stats_hash.record(specs, value, aux, &blk)
    end
  end
end
record_unscoped_metrics(state, metric_names, value = nil, aux = nil, &blk) click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 68
def record_unscoped_metrics(state, metric_names, value = nil, aux = nil, &blk)
  txn = state.current_transaction
  if txn
    txn.metrics.record_unscoped(metric_names, value, aux, &blk)
  else
    specs = coerce_to_metric_spec_array(metric_names, nil)
    with_stats_lock do
      @stats_hash.record(specs, value, aux, &blk)
    end
  end
end
reset!() click to toggle source
# File lib/new_relic/agent/stats_engine.rb, line 130
def reset!
  with_stats_lock do
    old = @stats_hash
    @stats_hash = StatsHash.new
    old
  end
end
tl_record_scoped_and_unscoped_metrics(scoped_metric, summary_metrics = nil, value = nil, aux = nil, &blk) click to toggle source

Like tl_record_unscoped_metrics, but records a scoped metric as well.

This is an internal method, subject to change at any time. Client apps and gems should use the public API (NewRelic::Agent.record_metric) instead.

The given scoped_metric will be recoded as both a scoped and an unscoped metric. The summary_metrics will be recorded as unscoped metrics only.

If called during a transaction, all metrics will be attached to the Transaction, and not merged into the global set of metrics until the end of the transaction.

If called outside of a transaction, only the unscoped metrics will be recorded, directly into the global set of metrics (under a lock).

@api private

# File lib/new_relic/agent/stats_engine.rb, line 99
def tl_record_scoped_and_unscoped_metrics(scoped_metric, summary_metrics = nil, value = nil, aux = nil, &blk)
  state = NewRelic::Agent::Tracer.state
  record_scoped_and_unscoped_metrics(state, scoped_metric, summary_metrics, value, aux, &blk)
end
tl_record_supportability_metric_count(metric, value) click to toggle source

Helper for recording a straight value into the count

# File lib/new_relic/agent/stats_engine.rb, line 123
def tl_record_supportability_metric_count(metric, value)
  real_name = "Supportability/#{metric}"
  tl_record_unscoped_metrics(real_name) do |stat|
    stat.call_count = value
  end
end
tl_record_unscoped_metrics(metric_names, value = nil, aux = nil, &blk) click to toggle source

Update the unscoped metrics given in metric_names. metric_names may be either a single name, or an array of names.

This is an internal method, subject to change at any time. Client apps and gems should use the public API (NewRelic::Agent.record_metric) instead.

There are four ways to use this method:

  1. With a numeric value, it will update the Stats objects associated with the given metrics by calling record_data_point(value, aux). aux will be treated in this case as the exclusive time associated with the call being recorded.

  2. With a value of :apdex_s, :apdex_t, or :apdex_f, it will treat the associated stats as an Apdex metric, updating it to reflect the occurrence of a transaction falling into the given category. The aux value in this case should be the apdex threshold used in bucketing the request.

  3. If a block is given, value and aux will be ignored, and instead the Stats object associated with each named unscoped metric will be yielded to the block for customized update logic.

  4. If value is a Stats instance, it will be merged into the Stats associated with each named unscoped metric.

If this method is called during a transaction, the metrics will be attached to the Transaction, and not merged into the global set until the end of the transaction.

Otherwise, the metrics will be recorded directly into the global set of metrics, under a lock.

@api private

# File lib/new_relic/agent/stats_engine.rb, line 63
def tl_record_unscoped_metrics(metric_names, value = nil, aux = nil, &blk)
  state = NewRelic::Agent::Tracer.state
  record_unscoped_metrics(state, metric_names, value, aux, &blk)
end
to_h() click to toggle source

For use by test code only.

# File lib/new_relic/agent/stats_engine.rb, line 193
def to_h
  with_stats_lock { @stats_hash.to_h }
end
with_stats_lock() { || ... } click to toggle source

All access to the @stats_hash ivar should be funnelled through this method to ensure thread-safety.

# File lib/new_relic/agent/stats_engine.rb, line 23
def with_stats_lock
  @stats_lock.synchronize { yield }
end