From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Preview: portable dumper Date: Fri, 02 Dec 2016 16:45:44 +0200 Message-ID: <83shq6mlt3.fsf@gnu.org> References: <047a67ec-9e29-7e4e-0fb0-24c3e59b5886@dancol.org> <83zikjxt1j.fsf@gnu.org> <8360n6ruzu.fsf@gnu.org> <834m2nplmb.fsf@gnu.org> <83inr2oje6.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1480689981 20665 195.159.176.226 (2 Dec 2016 14:46:21 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 2 Dec 2016 14:46:21 +0000 (UTC) Cc: emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Dec 02 15:46:17 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cCp6M-0004V8-D3 for ged-emacs-devel@m.gmane.org; Fri, 02 Dec 2016 15:46:14 +0100 Original-Received: from localhost ([::1]:34914 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cCp6Q-0007nB-9F for ged-emacs-devel@m.gmane.org; Fri, 02 Dec 2016 09:46:18 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36097) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cCp5o-0007mu-ML for emacs-devel@gnu.org; Fri, 02 Dec 2016 09:45:41 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cCp5k-0007o5-70 for emacs-devel@gnu.org; Fri, 02 Dec 2016 09:45:40 -0500 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:54658) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cCp5k-0007o1-3h; Fri, 02 Dec 2016 09:45:36 -0500 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:1708 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1cCp5j-0001aL-Ch; Fri, 02 Dec 2016 09:45:35 -0500 In-reply-to: (message from Stefan Monnier on Fri, 02 Dec 2016 08:04:46 -0500) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:209921 Archived-At: > From: Stefan Monnier > Cc: emacs-devel@gnu.org > Date: Fri, 02 Dec 2016 08:04:46 -0500 > > > Granted, the proposed dumper is not very complicated. But it isn't > > trivial either. So if we can achieve a similar effect by using the > > "normal" loadup code, which is much simpler and doesn't really require > > understanding anything new, I think it's more beneficial for the > > project's future. > > Ken worked on speeding up the lread.c code, and it got to be > significantly faster, but not fast enough. AFAIK it's got to the point > where it's not clear exactly how to speed it up further. Not that it > can't be done, but that it's not obvious how, so it's likely going to > require some serious rethinking and maybe restructuring/rewrite of > the code. > > Is it going to happen if we don't merge the pdumper? I'm not so sure. I'm willing to give that a chance. I don't see any reason to make the decision today. > The main impetus behind speeding up lread.c is to replace unexec.c, so > I agree with you that merging the pdumper might mean that speeding up > lread.c will simply never happen. But I think there's also a very > serious risk that even without the pdumper, speeding up lread.c will > still never happen: I have no intention on working at speeding up > lread.c, AFAICT Ken also gave up on it, anyone else? Judging by Ken's response, he didn't give up yet. In any case, it should be clear to anyone that code which isn't written cannot be used. So a reality check will get us straight. > Personally, I think that maybe we should move in the other direction: > keep lread.c for "source code" and generalize the pdumper code so it can > also be used for the .elc files. You mean, move the byte compiler to C? If not, I don't understand the idea: pdump wants a file in a very specific format, because it doesn't really understand the entities it reads.