gitlab-org--gitlab-foss/lib/gitlab/metrics/method_call.rb
Yorick Peterse 905f8d763a
Reduce instrumentation overhead
This reduces the overhead of the method instrumentation code primarily
by reducing the number of method calls. There are also some other small
optimisations such as not casting timing values to Floats (there's no
particular need for this), using Symbols for method call metric names,
and reducing the number of Hash lookups for instrumented methods.

The exact impact depends on the code being executed. For example, for a
method that's only called once the difference won't be very noticeable.
However, for methods that are called many times the difference can be
more significant.

For example, the loading time of a large commit
(nrclark/dummy_project@81ebdea5df)
was reduced from around 19 seconds to around 15 seconds using these
changes.
2016-07-28 16:56:17 +02:00

52 lines
1.3 KiB
Ruby

module Gitlab
module Metrics
# Class for tracking timing information about method calls
class MethodCall
attr_reader :real_time, :cpu_time, :call_count
# name - The full name of the method (including namespace) such as
# `User#sign_in`.
#
# series - The series to use for storing the data.
def initialize(name, series)
@name = name
@series = series
@real_time = 0
@cpu_time = 0
@call_count = 0
end
# Measures the real and CPU execution time of the supplied block.
def measure
start_real = System.monotonic_time
start_cpu = System.cpu_time
retval = yield
@real_time += System.monotonic_time - start_real
@cpu_time += System.cpu_time - start_cpu
@call_count += 1
retval
end
# Returns a Metric instance of the current method call.
def to_metric
Metric.new(
@series,
{
duration: real_time,
cpu_duration: cpu_time,
call_count: call_count
},
method: @name
)
end
# Returns true if the total runtime of this method exceeds the method call
# threshold.
def above_threshold?
real_time >= Metrics.method_call_threshold
end
end
end
end