Issue #14937 has been updated by MSP-Greg (Greg L). @normalperson Eric, In addition to the build mentioned above, there have been two more ruby-loco builds, both with all three patches, and both passed all tests > Thanks for testing; I guess 47 minutes is not unusual for a busy CI machine? Re Appveyor: * 6 minutes is updating the build system * I think each CI is run on 2 cores of a 4 core system, the system may be competing with another CI for disk IO, etc. The build for r64024 completed in 37 minutes. * I run both make test-rubyspec and mspec. * I think MJIT is one of the longer running suites, and with retry, it is always run twice. Thanks again, Greg ---------------------------------------- Misc #14937: [PATCH] thread_pthread: lazy-spawn timer-thread only on contention https://bugs.ruby-lang.org/issues/14937#change-73128 * Author: normalperson (Eric Wong) * Status: Open * Priority: Normal * Assignee: ---------------------------------------- [ruby-core:87773] ``` thread_pthread: lazy-spawn timer-thread only on contention To reduce resource use and reduce CI failure; lazy spawn timer-thread only in processes which use Ruby Threads AND those Ruby Threads hit contention. Single-threaded Ruby processes (including forked children) will never have timer-thread overhead. To simplify the thread_pthread.c code, I eliminated busy timer thread [Misc #14851]. Maybe the thread_win32.c code can use self-pipe, too; and they won't need busy wakeups. There is only one self-pipe, now, as wakeups for timeslice are handled via condition variables. This reduces FD pressure slightly. Signal handling is handled directly by one Ruby Thread (instead of timer-thread) by exposing signal self-pipe to callers of rb_thread_fd_select, native_sleep, rb_wait_for_single_fd, etc... Acquiring, using, and releasing the self-pipe is exposed via 4 new internal functions: 1) rb_sigwait_fd_get - exclusively acquire timer_thread_pipe.normal[0] 2) rb_sigwait_fd_sleep - sleep and wait for signal (and no other FDs) 3) rb_sigwait_fd_put - release acquired result from rb_sigwait_fd_get 4) rb_sigwait_fd_migrate - migrate signal handling to another thread after calling rb_sigwait_fd_put. rb_sigwait_fd_migrate is necessary for waitpid callers because only one thread can wait on self-pipe at a time, otherwise a deadlock will occur if threads fight over the self-pipe. TRAP_INTERRUPT_MASK is now set for the main thread directly in signal handler via rb_thread_wakeup_timer_thread. Originally, I wanted to use POSIX timers (timer_create/timer_settime) and avoid timer-thread completely. Unfortunately, this proved unfeasible for one reason: Mutex#sleep resumes on spurious wakeups and test/thread/test_cv.rb::test_condvar_timed_wait failed. In the future, I hope [Feature #14717] is accepted so Threads may be made non-preemptible. This will allow users to prevent timer-thread creation completely. ``` git repository also available at: https://80x24.org/ruby.git tt-lazy (commit a2990cefccba55300ad44275ee4adf18e6f95ece) ---Files-------------------------------- 0001-thread_pthread-lazy-spawn-timer-thread-only-on-conte.patch (42.3 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe> <http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>