From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Against sqlite3!!! Date: Tue, 07 Dec 2021 14:52:08 -0500 Message-ID: References: <41E1B5BD-879C-430C-8BA3-3A5354AF2928@mit.edu> <87tufkwga9.fsf@gnu.org> <28E143D2-5C8F-4CDC-B6CE-15F672A00AB1@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14198"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: Tassilo Horn , "emacs-devel@gnu.org" , Zhu Zihao To: Qiantan Hong Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Dec 07 20:53:15 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 1mugWW-0003KY-Os for ged-emacs-devel@m.gmane-mx.org; Tue, 07 Dec 2021 20:53:12 +0100 Original-Received: from localhost ([::1]:41336 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mugWV-0004jq-9D for ged-emacs-devel@m.gmane-mx.org; Tue, 07 Dec 2021 14:53:11 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:54880) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mugVq-0003iN-H8 for emacs-devel@gnu.org; Tue, 07 Dec 2021 14:52:30 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:14993) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mugVn-0006FF-Q3; Tue, 07 Dec 2021 14:52:30 -0500 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 28BD9441479; Tue, 7 Dec 2021 14:52:25 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id A7623440781; Tue, 7 Dec 2021 14:52:19 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1638906739; bh=/Wgd/iH9bpZEfpxc1qrDv6qoLIKxmcs8CBqu+HFa+wo=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=kdfSE/wgV+ueLNAGTATIUU59VfXTivKagXF8qsD+ruSU2DAs8s1juGScN2LgN+xXg x5yk2J4mr2XNAOCcRLZTOErvwuQJovgSC/LufnfmNmq4+aXAqWxBLwSAwnPLbnuoyY px8icRPjaiCkCScL4oshh+I2CESFQ6M2TqHnJTS074gpQ0APCcQp+VsFxwP9rhTcCe kFU20KNV1izmFwXxaqP8QGOZJHliNG26Gsm6MjHIUsA2Gizr3sNaEot+NePZJlKLp0 G0EOtX7tRk/y34juVrUVLDDkMABMyLZFsubzTYZbqS68OJL93yYUHjazsCsTY0o+Ct pekQmznUaPL+A== Original-Received: from alfajor (lechon.iro.umontreal.ca [132.204.27.242]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 952451208ED; Tue, 7 Dec 2021 14:52:19 -0500 (EST) In-Reply-To: <28E143D2-5C8F-4CDC-B6CE-15F672A00AB1@mit.edu> (Qiantan Hong's message of "Tue, 7 Dec 2021 16:35:47 +0000") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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:281274 Archived-At: > Since it records a log of deltas instead of printing the whole data struc= ture, > different key won=E2=80=99t interfere. > Being said that, currently it probably won=E2=80=99t work because UNIX ap= pend > is not atomic and will probably be interleaved into nonsense. > There=E2=80=99re various workarounds, lock file being one, but I like > the idea of keeping only one =E2=80=9Ccontroller=E2=80=9D instance with e= xclusive > access to the file more. I think allowing several instances to use the file at the same time is important (I always have 2 sessions active at the same time and I'd like to be able to use (and share) savehist with both of them). But that only means having to lock while we're saving, which is a very short time. It also requires being able to refresh the in-memory data once we detect that the ondisk data has been changed. Stefan