Release 0.17.0

[miry]

Version 0.17.0

• Avoid chaining duplicated semian identifiers in error messages #423
• Use monotonic time for checking last error #441
• Replace Time.now with monotonic in lru cache and resource update #443
• Update comment for Semian.register method #425
• Mention about postgres adapter #440
• Support Ruby 3.2 #463
• Enable write barrier protection on Resource #469

Postpone

• Extract bulkheading ENV settings to configuration part #442
• Benchmark and performance review between versions #467

[miry]

Performance report

Current version has main 2 performance improvements.
It will not be visible in small application,
but could be effective for application with a lot of client requests.

1. Remove checking if semian disabled on each acquire

potentially saves latency and extra calls of ENV per each client request (4 calls less).

2. Replace Time.now with Monotonic clock

Improve performance of execution Semian::CircuitBreaker#transition_to_half_open? by 25%.

In total execution of Semian::CircuitBreaker#acquire decreased from 41ms to 30ms.

[miry]

Tested new changes on my project. It required to update tests to not just freeze realtime, but also monotonic.

Found activerecord with opentelemetry uses different kind of invokes clock_gettime:

# frozen_string_literal: true

module TimeHelper
  def time_travel(val)
    now_monotonic = Process.clock_gettime(Process::CLOCK_MONOTONIC)
    now_realtime_nanosec = Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond)
    now_timestamp = Time.now
    now_zone_timestamp = Time.zone.now
    cpu_thread_cputime_id = Process.clock_gettime(Process::CLOCK_THREAD_CPUTIME_ID)

    new_monotonic = now_monotonic + val
    Process.stubs(:clock_gettime).with(Process::CLOCK_MONOTONIC).returns(new_monotonic)
    Process.stubs(:clock_gettime).with(Process::CLOCK_MONOTONIC, :float_millisecond).returns(new_monotonic*1000)
    Process.stubs(:clock_gettime).with(Process::CLOCK_MONOTONIC, :nanosecond).returns((new_monotonic*(10**9)).to_i)
    Process.stubs(:clock_gettime).with(Process::CLOCK_REALTIME, :nanosecond).returns(now_realtime_nanosec)
    Process.stubs(:clock_gettime).with(Process::CLOCK_THREAD_CPUTIME_ID).returns(cpu_thread_cputime_id)
    Process.stubs(:clock_gettime).with(Process::CLOCK_THREAD_CPUTIME_ID, :float_millisecond).returns(cpu_thread_cputime_id*1000)

    new_timestamp = now_timestamp + val
    Time.stubs(:now).returns(new_timestamp)

    now_zone_timestamp = now_zone_timestamp + val
    Time.zone.stubs(:now).returns(now_zone_timestamp)

    yield
  ensure
    Time.zone.unstub(:now)
    Time.unstub(:now)
    Process.unstub(:clock_gettime)
  end
end

[miry]

Tested semian on our biggest private repo. Tests were passed. Going to release a new version tomorrow.