On 2017/04/27 12:57, Eric Wong wrote: > https://80x24.org/spew/20170427034243.22272-1-e / 80x24.org/raw Thank you. I understand the idea. My understanding is "Do not rely on native cond, but manage sleeping threads by ourselves (manage waiting queue)". It sound great. However, I can't understand well about changing native_sleep(). Before native_sleep(), GVL was acquired and UBF is zero. What kind of sequence do you think which requires [Misc #13514]? Thanks, Koichi -- // SASADA Koichi at atdot dot net Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe> <http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>