From: ko1@... Date: 2017-05-02T09:21:26+00:00 Subject: [ruby-core:80974] [Ruby trunk Feature#13517] [PATCH] reduce rb_mutex_t size from 160 to 80 bytes on 64-bit Issue #13517 has been updated by ko1 (Koichi Sasada). At a glance, it seems nice. But I need to time to check deeply. I'll check with 'Misc #13514'. Please wait these days. In Japan, now we have holiday week. I'll check on these days. Thanks, Koichi ---------------------------------------- Feature #13517: [PATCH] reduce rb_mutex_t size from 160 to 80 bytes on 64-bit https://bugs.ruby-lang.org/issues/13517#change-64636 * Author: normalperson (Eric Wong) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- ``` Instead of relying on a native condition variable and mutex for every Ruby Mutex object, use a doubly linked-list to implement a waiter queue in the Mutex. The immediate benefit of this is reducing the size of every Mutex object, as some projects have many objects requiring synchronization. In the future, this technique using a linked-list and on-stack list node (struct mutex_waiter) should allow us to easily transition to M:N threading model, as we can avoid the native thread dependency to implement Mutex. We already do something similar for autoload in variable.c, and this was inspired by the Linux kernel wait queue (as ccan/list is inspired by the Linux kernel linked-list). Finaly, there are big performance improvements for Mutex benchmarks, especially in contended cases: measure target: real name |trunk |built ----------------|------:|------: loop_whileloop2 | 0.149| 0.148 vm2_mutex* | 0.893| 0.651 vm_thread_mutex1| 0.809| 0.624 vm_thread_mutex2| 2.608| 0.628 vm_thread_mutex3| 28.227| 0.881 Speedup ratio: compare with the result of `trunk' (greater is better) name |built ----------------|------: loop_whileloop2 | 1.002 vm2_mutex* | 1.372 vm_thread_mutex1| 1.297 vm_thread_mutex2| 4.149 vm_thread_mutex3| 32.044 Tested on AMD FX-8320 8-core at 3.5GHz ``` ---Files-------------------------------- 0001-reduce-rb_mutex_t-size-from-160-to-80-bytes-on-64-bi.patch (9.17 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: