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: sqlite3 Date: Tue, 14 Dec 2021 17:43:45 +0100 Message-ID: <87tufbnnlq.fsf@gnus.org> References: <87tufmjyai.fsf@gnus.org> <87lf0nr2b4.fsf@gnus.org> 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="12490"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Dmitry Gutov Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Dec 14 17:44:55 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 1mxAv9-00036l-GC for ged-emacs-devel@m.gmane-mx.org; Tue, 14 Dec 2021 17:44:55 +0100 Original-Received: from localhost ([::1]:56430 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mxAv7-00030S-4G for ged-emacs-devel@m.gmane-mx.org; Tue, 14 Dec 2021 11:44:54 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:44990) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mxAuA-0001cz-B3 for emacs-devel@gnu.org; Tue, 14 Dec 2021 11:43:54 -0500 Original-Received: from [2a01:4f9:2b:f0f::2] (port=60568 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 1mxAu8-0007HV-R6 for emacs-devel@gnu.org; Tue, 14 Dec 2021 11:43:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Message-ID :In-Reply-To:Date:References:Subject:Cc:To:From:Sender:Reply-To: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=6tSyy6yH2dJlc3KadK/aKfmUc9KxyCkmVdYVtCccyvQ=; b=RjulxNcfH8VS/Vk60QfBhmYvTJ uIfAPDaVFTnXa5c/QEr6GL2aFh3I+ahpLpePz+aMDNw5vLe/lBZ8eYmvLp85p4FT3QBbh4Mt93dKR rLm54XZPy4Tsg2dU39cE6S5nSo4idQNwG7TKIzFZ+3Md2KsRW9ZSbPd9KicD8WF4xSLU=; 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 1mxAu3-0003ft-Hs; Tue, 14 Dec 2021 17:43:50 +0100 Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAABGdBTUEAALGPC/xhBQAAACBj SFJNAAB6JgAAgIQAAPoAAACA6AAAdTAAAOpgAAA6mAAAF3CculE8AAAAD1BMVEVORz8eHx23nVLB 0cn///8vnA2VAAAAAWJLR0QEj2jZUQAAAAd0SU1FB+UMDhAiNDVSq0YAAAGHSURBVDjLdVSNucMg CASzANgFDC5gw/67vUNj8/v80kg4uUPEErG+DSH9Z1yAGSx3QK8AD+vnFSUKQIiQAOMNizNmSsw9 gmhVyswAVAqXtAMrUZFEHBGgwHp8RLpwle7btURkRMT8TK5rYCGn8b3eN5i8707GxD3dUBG3Lyb9 uAfMMwJ+a8Kii/s2vDR43EqFmFY396JYEsCy4StVBoOH6W0CFoCtotmpevW2U2WjaqEe2t7cv7u4 bFatbta1fVt6yl0cVPEItEG0uM50P/Cui5N6aHhDBUftssFpYPAGff8G0yjq5pytalCx+xo1GTuH OIb2jfeiTOADcWsjXdDN6iKHAMCQA+Bz2fMWElgwA37nIbU7FlTw1onn1roA/Abw6TffdJjMD+Do W75S3QF5XBw6uM4AH8Zo490hdAgLUyqeqPRnS9TCMNgWvQ+Y4uJgtLBTCfNXC4rzpOg12WaX8C0r J9a3dNXTHRg3SuvyCsSp8PsfAFqu3/MHQCmA7M+i0L26p2P8A3hQUvGyC4YWAAAAJXRFWHRkYXRl OmNyZWF0ZQAyMDIxLTEyLTE0VDE2OjM0OjUyKzAwOjAwK2xf3AAAACV0RVh0ZGF0ZTptb2RpZnkA MjAyMS0xMi0xNFQxNjozNDo1MiswMDowMFox52AAAAAASUVORK5CYII= X-Now-Playing: The Art of Noise's _Who's Afraid of...!_: "Beat Box (Diversion One)" In-Reply-To: (Dmitry Gutov's message of "Tue, 14 Dec 2021 19:31:58 +0300") 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:281920 Archived-At: Dmitry Gutov writes: > But a "proper" database might give other advantages like a faster > search in the loaded data (unless it's already "indexed" by using hash > tables everywhere where they could be used). > > Or being able to read the data without loading the whole file into > memory. Which, for certain scenarios and data sets, might be a bigger > advantage than faster writes. Here's a matrix of advantages and disadvantages to three approaches: sqlite, one-file-per-value, and one-file-with-a-hash-table-with-several/all-values: =20=20 sqlite files hash Read/write value speed =E2=9A=84 =E2=9A=85 =E2=9A=80 Read/write value mem =E2=9A=85 =E2=9A=84 =E2=9A=80 List all values speed =E2=9A=85 =E2=9A=80 =E2=9A=85 List all values mem =E2=9A=83 =E2=9A=81 =E2=9A=83 Ease of moving around =E2=9A=84 =E2=9A=80 =E2=9A=85 >> But it turns out that sqlite3 is actually slower for this particular use >> case than just writing the data to a file (i.e., using the file system >> as the database; one file per value). So multisession.el now offers two >> backends (`files' and `sqlite'), and defaults to `files'. > > Does the latter scenario use as many files as you do 'COMMIT' in the > former scenario? No, if you (cl-incf (multisession-value foo)) you'll get one COMMIT per time, but there'll only be one foo.value file (at a time). --=20 (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no