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</o:shapelayout></xml><![endif]--></head><body lang=SV link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='margin-left:65.2pt'><b><span lang=EN-US>From:</span></b><span lang=EN-US> Sean Hinde <sean.hinde@mac.com> <br><b>Sent:</b> den 24 november 2020 19:16<br><b>To:</b> Sverker Eriksson <sverker.eriksson@ericsson.com><br><b>Cc:</b> Erlang Questions <erlang-questions@erlang.org><br><b>Subject:</b> Re: Are NIF resources meant to be destroyed immediately on GC?<o:p></o:p></span></p></div></div><p class=MsoNormal style='margin-left:65.2pt'><o:p> </o:p></p><p class=MsoNormal style='margin-left:65.2pt'><o:p> </o:p></p><div><p class=MsoNormal style='margin-left:65.2pt'><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal style='margin-left:65.2pt'>On 23 Nov 2020, at 23:16, Sverker Eriksson <<a href="mailto:sverker.eriksson@ericsson.com">sverker.eriksson@ericsson.com</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal style='margin-left:65.2pt'><o:p> </o:p></p><div><div><p class=MsoNormal style='margin-left:65.2pt'><span lang=EN-US>Prior to OTP 22.0 resource destructors were called directly by the thread that happened to decrease the reference counter down to zero.</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'><span lang=EN-US>From OTP 22.0 resource destructors are scheduled. This in order to ensure a stable known execution context for the destructor callback. So it may not have executed when erlang:garbage_collect returns, but will very soon (unless you have a very overloaded system or a bug preventing ref counter from reaching zero).</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'><span lang=EN-US> </span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'><span lang=EN-US>/Sverker, Erlang/OTP</span><o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'><span lang=EN-US> </span><o:p></o:p></p></div></div></blockquote><p class=MsoNormal style='margin-left:65.2pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'>This a really nice change. It opens the door to resource destructors being safe for closing external resources like database handles that might take a while.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:65.2pt'>Super cool!<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>Sorry to disappoint, but no.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>By ”scheduled” I just meant “put in run queue to be executed at a later time”. Destructors are still executed by a normal scheduler threads and not dirty schedulers.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>/Sverker<o:p></o:p></span></p></div></div></body></html>