From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Opportunistic GC Date: Mon, 08 Mar 2021 19:13:07 +0200 Message-ID: <83tuplr2l8.fsf@gnu.org> References: Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="33447"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org, pipcet@gmail.com, akrl@sdf.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Mar 08 18:42:49 2021 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lJJu5-0008ZQ-K2 for ged-emacs-devel@m.gmane-mx.org; Mon, 08 Mar 2021 18:42:49 +0100 Original-Received: from localhost ([::1]:41766 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lJJu4-0001ex-J4 for ged-emacs-devel@m.gmane-mx.org; Mon, 08 Mar 2021 12:42:48 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:49666) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lJJRV-0006ox-Bo for emacs-devel@gnu.org; Mon, 08 Mar 2021 12:13:17 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:52033) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lJJRT-0006XW-ND; Mon, 08 Mar 2021 12:13:15 -0500 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:1892 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1lJJRQ-0002eO-Vw; Mon, 08 Mar 2021 12:13:14 -0500 In-Reply-To: (message from Stefan Monnier on Mon, 08 Mar 2021 11:44:05 -0500) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:266212 Archived-At: > From: Stefan Monnier > Cc: Pip Cet , eliz@gnu.org, emacs-devel@gnu.org > Date: Mon, 08 Mar 2021 11:44:05 -0500 > > > I also expect fork will work, I'm more wondering about interaction with > > sockets file descriptors or anything else in our codebase and/or in > > libraries we have loaded. > > I suspect we wouldn't want to use `fork` literally, but rather something > like Linux's `clone` so as to have more control about what is > really shared. Basically, we just want to spawn a thread, except it runs > in a snapshot of the heap. There are other potential complications with this, related to threads. Posix says 'fork' only copies a single thread, the one that called it, but what if that single thread is not the main thread? In Emacs nowadays a non-main Lisp thread can trigger GC. What happens to the mutexes we use in the threads machinery when we fork like that?