gitlab-org--gitlab-foss/lib/gitlab/metrics/system.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

62 lines
1.7 KiB
Ruby

module Gitlab
module Metrics
# Module for gathering system/process statistics such as the memory usage.
#
# This module relies on the /proc filesystem being available. If /proc is
# not available the methods of this module will be stubbed.
module System
if File.exist?('/proc')
# Returns the current process' memory usage in bytes.
def self.memory_usage
mem = 0
match = File.read('/proc/self/status').match(/VmRSS:\s+(\d+)/)
if match and match[1]
mem = match[1].to_f * 1024
end
mem
end
def self.file_descriptor_count
Dir.glob('/proc/self/fd/*').length
end
else
def self.memory_usage
0.0
end
def self.file_descriptor_count
0
end
end
# THREAD_CPUTIME is not supported on OS X
if Process.const_defined?(:CLOCK_THREAD_CPUTIME_ID)
def self.cpu_time
Process.
clock_gettime(Process::CLOCK_THREAD_CPUTIME_ID, :millisecond)
end
else
def self.cpu_time
Process.
clock_gettime(Process::CLOCK_PROCESS_CPUTIME_ID, :millisecond)
end
end
# Returns the current real time in a given precision.
#
# Returns the time as a Float.
def self.real_time(precision = :millisecond)
Process.clock_gettime(Process::CLOCK_REALTIME, precision)
end
# Returns the current monotonic clock time in a given precision.
#
# Returns the time as a Float.
def self.monotonic_time(precision = :millisecond)
Process.clock_gettime(Process::CLOCK_MONOTONIC, precision)
end
end
end
end