Module: NewRelic::Agent::StatsEngine::Transactions

Included in:
NewRelic::Agent::StatsEngine
Defined in:
lib/new_relic/agent/stats_engine/transactions.rb

Overview

Handles pushing and popping elements onto an internal stack that tracks where time should be allocated in Transaction Traces

Defined Under Namespace

Modules: Shim

Instance Method Summary collapse

Instance Method Details

#end_transaction ⇒ Object

Try to clean up gracefully, otherwise we leave things hanging around on thread locals. If it looks like a transaction is still in progress, then maybe this is an inner transaction and is ignored.



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 111

def end_transaction
  elapsed = GCProfiler.capture
  if @transaction_sampler && @transaction_sampler.last_sample
    @transaction_sampler.last_sample.params[:custom_params] ||= {}
    @transaction_sampler.last_sample.params[:custom_params][:gc_time] = elapsed
  end
  stack = scope_stack

  if stack && stack.empty?
    Thread::current[:newrelic_scope_stack] = nil
    Thread::current[:newrelic_scope_name] = nil
  end
end

#peek_scope ⇒ Object

Returns the latest ScopeStackElement



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 78

def peek_scope
  scope_stack.last
end

#pop_scope(expected_scope, duration, time = Time.now.to_f) ⇒ Object

Pops a scope off the transaction stack - this updates the transaction sampler that we’ve finished execution of a traced method



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 57

def pop_scope(expected_scope, duration, time=Time.now.to_f)
  stack = scope_stack
  scope = stack.pop
  fail "unbalanced pop from blame stack, got #{scope ? scope.name : 'nil'}, expected #{expected_scope ? expected_scope.name : 'nil'}" if scope != expected_scope

  if !stack.empty?
    if scope.deduct_call_time_from_parent
      stack.last.children_time += duration
    else
      stack.last.children_time += scope.children_time
    end
  end
  @transaction_sampler.notice_pop_scope(scope.name, time) if sampler_enabled?
  scope
end

#push_scope(metric, time = Time.now.to_f, deduct_call_time_from_parent = true) ⇒ Object

Pushes a scope onto the transaction stack - this generates a TransactionSample::Segment at the end of transaction execution



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 47

def push_scope(metric, time = Time.now.to_f, deduct_call_time_from_parent = true)
  stack = scope_stack
  @transaction_sampler.notice_push_scope metric, time if sampler_enabled?
  scope = ScopeStackElement.new(metric, deduct_call_time_from_parent)
  stack.push scope
  scope
end

#remove_transaction_sampler(l) ⇒ Object

removes a transaction sampler



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 41

def remove_transaction_sampler(l)
  @transaction_sampler = nil
end

#sampler_enabled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 73

def sampler_enabled?
  @transaction_sampler && Agent.config[:'transaction_tracer.enabled']
end

#scope_name ⇒ Object

Returns the current scope name from the thread local



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 95

def scope_name
  Thread::current[:newrelic_scope_name]
end

#scope_name=(transaction) ⇒ Object

set the name of the transaction for the current thread, which will be used to define the scope of all traced methods called on this thread until the scope stack is empty.

currently the transaction name is the name of the controller action that is invoked via the dispatcher, but conceivably we could use other transaction names in the future if the traced application does more than service http request via controller actions



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 90

def scope_name=(transaction)
  Thread::current[:newrelic_scope_name] = transaction
end

#start_transaction(name = nil) ⇒ Object

Start a new transaction, unless one is already in progress



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 100

def start_transaction(name = nil)
  Thread::current[:newrelic_scope_stack] ||= []
  self.scope_name = name if name
  NewRelic::Agent.instance.events.notify(:start_transaction, name)
  GCProfiler.init
end

#transaction_sampler=(sampler) ⇒ Object

add a new transaction sampler, unless we’re currently in a transaction (then we fail)



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# File 'lib/new_relic/agent/stats_engine/transactions.rb', line 35

def transaction_sampler= sampler
  fail "Can't add a scope listener midflight in a transaction" if scope_stack.any?
  @transaction_sampler = sampler
end