From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.devel Subject: Re: Mutating existing persistent data Date: Tue, 07 Dec 2021 06:41:02 +0100 Message-ID: <87ilw1ht01.fsf@gnus.org> References: <87tufmjyai.fsf@gnus.org> <875ys2lyt0.fsf@yahoo.com> <87wnkhlxb9.fsf@yahoo.com> <2FD7D920-D92C-480B-B2AC-91A17F0397C4@mit.edu> <87zgpdi0rk.fsf@gnus.org> <878rwxje1x.fsf@yahoo.com> <87v901huhw.fsf@gnus.org> <87v901htvj.fsf@yahoo.com> <87mtldhtpy.fsf@gnus.org> <87r1apht83.fsf@yahoo.com> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="8260"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: Qiantan Hong , John Yates , Stefan Monnier , Arthur Miller , "emacs-devel@gnu.org" To: Po Lu Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Dec 07 06:42:22 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 1muTF8-0001y1-8v for ged-emacs-devel@m.gmane-mx.org; Tue, 07 Dec 2021 06:42:22 +0100 Original-Received: from localhost ([::1]:56814 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1muTF7-0007P2-1m for ged-emacs-devel@m.gmane-mx.org; Tue, 07 Dec 2021 00:42:21 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:60148) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1muTE4-0006dH-Cw for emacs-devel@gnu.org; Tue, 07 Dec 2021 00:41:16 -0500 Original-Received: from [2a01:4f9:2b:f0f::2] (port=34790 helo=quimby.gnus.org) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1muTE2-0003pm-Qg for emacs-devel@gnu.org; Tue, 07 Dec 2021 00:41:16 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=713y4rW1zyHRj7T8v4Mi4pwTsIg48kUuHRPJ1WixIdk=; b=uRn4rQRXZUw3Jb4IsKikPub60r 34Rd6k7RPPNKjfVu+d0+JYIkZbL3g7mJE/4UcP10wOZaauVOPYkFijdC6wNLYtwRmrNihWfYb9NI1 mLTbdfakw2IWPNKq5oETKgjjqfTf7vWVsxoGdC9N4aDYQ0Q9z80MSh6zLl+De86M3vxo=; Original-Received: from [84.212.220.105] (helo=xo) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1muTDr-0003sU-G3; Tue, 07 Dec 2021 06:41:06 +0100 Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAABGdBTUEAALGPC/xhBQAAACBj SFJNAAB6JgAAgIQAAPoAAACA6AAAdTAAAOpgAAA6mAAAF3CculE8AAAAElBMVEXRwqT69d6ogltd RjAgFA7///+u9mQ5AAAAAWJLR0QF+G/pxwAAAAd0SU1FB+UMBwUKH6NW0r0AAAG1SURBVDjLdZOB keMwCEWRsgUoqsBGLsArVEAmov+a7gN2Npn4yIyd4Rk+IETpfmmJrkEhWq8j7ogA9X/xis9ha83M mcpaeaGAeagqJfg7cwVwQygHQOCCR8pEeNK9NPPrt0Zxv16Um+Ge/A2KAOzpo0TTo2IB/R2UF5gL JL8kqmpPB7Cv7UemWHViTJlilIYoecV1dqvsItVMVjHATQQZShZmq72s5hGATXUt99xQZjSVW28B Zsf34wTNpjoiQoitXwd1iui8oUAAXe+F/wCLcETobxyPA3ilDVRv4PEGkHkOJdkNzGIi4uUKtyeq kv3HZamJ94NUjXUMAzhjgXo7gI5pJ6j7tqPpBZ0EOE/BNNDcE/2K2gKcC8eLiQOQp7L9CQANtApf lJsPQEe5aDFrgKqxPvoI8Kgy5B20NcCsQ6enojD2kaAupLIzfYkP73xtulsAQBE3H4nI8qOPocux Pq4h+631jib6kOlNx3WwiDYlbb0j/v2qDe8jbU8Z5zIEiD7S9nuTzh8gIgbOptM3WFTHsXCfqXx5 5ofGOUQ99+oEsSVXgDK/7A+UY5QpvS5c3KD/2z8/UYVxzpVNRQAAACV0RVh0ZGF0ZTpjcmVhdGUA MjAyMS0xMi0wN1QwNToxMDozMSswMDowMAPHp3QAAAAldEVYdGRhdGU6bW9kaWZ5ADIwMjEtMTIt MDdUMDU6MTA6MzErMDA6MDBymh/IAAAAAElFTkSuQmCC X-Now-Playing: Simple Minds's _Sons and Fascination_: "This Earth That You Walk Upon" In-Reply-To: <87r1apht83.fsf@yahoo.com> (Po Lu's message of "Tue, 07 Dec 2021 13:36:12 +0800") X-Host-Lookup-Failed: Reverse DNS lookup failed for 2a01:4f9:2b:f0f::2 (failed) Received-SPF: pass client-ip=2a01:4f9:2b:f0f::2; envelope-from=larsi@gnus.org; helo=quimby.gnus.org X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RDNS_NONE=0.793, 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:281205 Archived-At: Po Lu writes: > I think the fallback mechanism should also store data to disk, perhaps > by serializing a hash table with `print' and writing it to a file. That would mean writing a lots of itsy bitsy files (i.e., using the file system as the DB) if this is going to have any kind of meaningful concurrency. Otherwise Emacsen will just be overwriting each other's data aggressively. And it'll be dog slow. So I don't see the use case. Virtually all systems have sqlite, and if the users have chosen to not build Emacs with it, they don't get the persistence feature. That's no different from when they choose to build without libxml -- they don't get to read web pages in Emacs. -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no