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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>this is funny, I am also working in this area currently.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Though I use spawnProcess for various reasons, not multiprocessing - which is also the recommendation on the ticket. And it makes sense.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>Nevertheless I'd be interested what happens if you try that on a kqueue-reactor OS .. ideally FreeBSD. OSX kqueue isn't the greatest.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>/Tobias<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Von:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> twisted-python-bounces@twistedmatrix.com [mailto:twisted-python-bounces@twistedmatrix.com] <b>Im Auftrag von </b>Flint<br><b>Gesendet:</b> Mittwoch, 23. Oktober 2013 17:46<br><b>An:</b> twisted-python@twistedmatrix.com<br><b>Betreff:</b> [Twisted-Python] epoll keep sharing state between process even after fork.<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi everybody<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I a came across a surprising problem when using the epoll based reactor.<o:p></o:p></p></div><div><p class=MsoNormal>(ticket here <a href="https://twistedmatrix.com/trac/ticket/6796">https://twistedmatrix.com/trac/ticket/6796</a>)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>As you can see on the ticket, the epoll object seems to share some state even after fork. <o:p></o:p></p></div><div><p class=MsoNormal>Which means even after having forked the process, making some changes to the inherited epoll object in one process may impact the one existing in another process !<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>This problem is only related to epoll based reactor, poll and select behave correctly.<o:p></o:p></p></div><div><p class=MsoNormal>I'm aware that some may say that this in not a twisted related problem (but an epoll issue), but I'm addressing my question here to try to figure out what would be the best workaround for this problem in a twisted based project ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>And for information this is what I have already tryed:<o:p></o:p></p></div><div><p class=MsoNormal>- I though about using poll or select reactor, but this is not possible, cause as i'm writing a library I do not decide which reactor will be installed by the person who want to use it.<o:p></o:p></p></div><div><p class=MsoNormal>(Besides as epoll is now the default reactor installed, I certainly want my library to work with it !)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>- Using spawnProcess as mentioned in the ticket comment, is not an option too, in my case, I need to share some state between the main process and subprocess. (I have on object in main process space that I want to inherit in all subprocess)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>- I (desperately) tryed to re-initialize the reactor._poller object after each fork to set it with a new object, but it was just a very bad idea ! :)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thank you, in advance, for any possible clue ! <o:p></o:p></p></div><div><p class=MsoNormal>(for information, my project is here <a href="https://github.com/Grindizer/scaletix">https://github.com/Grindizer/scaletix</a>)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>