From: normalperson@... Date: 2017-05-19T08:08:05+00:00 Subject: [ruby-core:81264] [Ruby trunk Feature#13575] [PATCH] speed up IO#close with many threads Issue #13575 has been reported by normalperson (Eric Wong). ---------------------------------------- Feature #13575: [PATCH] speed up IO#close with many threads https://bugs.ruby-lang.org/issues/13575 * Author: normalperson (Eric Wong) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- Today, it increases IO#close performance with many threads: Execution time (sec) name trunk after vm_thread_close 4.276 3.018 Speedup ratio: compare with the result of `trunk' (greater is better) name after vm_thread_close 1.417 This speedup comes because rb_notify_fd_close only scans threads inside rb_thread_io_blocking_region, not all threads in the VM. In the future, this type data structure may allow us to notify waiters of multiple FDs on a single thread (when using Fibers). * thread.c (struct waiting_fd): declare (rb_thread_io_blocking_region): use on-stack list waiter (rb_notify_fd_close): walk vm->waiting_fds instead (call_without_gvl): remove old field setting (th_init): ditto * vm_core.h (typedef struct rb_vm_struct): add waiting_fds list * (typedef struct rb_thread_struct): remove waiting_fd field (rb_vm_living_threads_init): initialize waiting_fds list I am now kicking myself for not thinking about this 3 years ago when I introduced ccan/list in [Feature #9632] to optimize this same function :< ---Files-------------------------------- 0001-speed-up-IO-close-with-many-threads.patch (4.66 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: