From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: =?utf-8?Q?Gerd_M=C3=B6llmann?= Newsgroups: gmane.emacs.devel Subject: Re: MPS codegen Date: Fri, 14 Jun 2024 09:56:07 +0200 Message-ID: References: <87le3b43qi.fsf@gmail.com> <86r0d21tqj.fsf@gnu.org> <877cetgqiz.fsf_-_@gmail.com> <87wmmsg2e4.fsf@gmail.com> <87plskg035.fsf@gmail.com> <87ed90fyd3.fsf@gmail.com> <86zfroxc6l.fsf@gnu.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="21392"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: eller.helmut@gmail.com, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Jun 14 09:56:59 2024 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 1sI1nv-0005NH-Kx for ged-emacs-devel@m.gmane-mx.org; Fri, 14 Jun 2024 09:56:59 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sI1nC-0004Fx-IF; Fri, 14 Jun 2024 03:56:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sI1nB-000444-96 for emacs-devel@gnu.org; Fri, 14 Jun 2024 03:56:13 -0400 Original-Received: from mail-ed1-x52f.google.com ([2a00:1450:4864:20::52f]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1sI1n9-0005w3-Iv; Fri, 14 Jun 2024 03:56:13 -0400 Original-Received: by mail-ed1-x52f.google.com with SMTP id 4fb4d7f45d1cf-57a44c2ce80so2116415a12.0; Fri, 14 Jun 2024 00:56:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1718351769; x=1718956569; darn=gnu.org; h=content-transfer-encoding:mime-version:user-agent:message-id:date :references:in-reply-to:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ofVbyUmo/w2Wr1MnAFUEeR5OeaxOZ2ogt++i/j088lA=; b=JNb93gBKrz3KTHSe51LjmoSyLGcDJKxYl/Y02aGfpVYH4nkeXGzuQtQT5Bql3Jn5W8 OosSY6/n2ui2gX0N/lhetyhXSWpZ0wJ5uTrlsgXbuQvh17JJQriHJGFAVzvOzDSqLCfF CVwEsU8DiBzMqut4Pfv89BFnbdpBvKRdRznrNXlRtAGxyy4NoP/sL6lPxKk2PvrKC4Gb JuRSsHhR5ARPh+G2QNH5Fw9dzL9LqLdBdS1aC8h+XwAfX1tRHqxGu1UOfgUZRi2M39uq VgCwWrYL4c+/KA2dWJ6rE+EPcWqTUHYcvl5kB0M1HvmpDIYF+WqgkLgo0x1DkqDU2bXI ahcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718351769; x=1718956569; h=content-transfer-encoding:mime-version:user-agent:message-id:date :references:in-reply-to:subject:cc:to:from:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=ofVbyUmo/w2Wr1MnAFUEeR5OeaxOZ2ogt++i/j088lA=; b=ELwGYMXkX9OsPj5HmZCpW3WhEi1bwpKa2cEzhArM9Fh3MJWZmGmOtsAIb9S+Si+iOk U84/J70rPLrF3MiP5UvrrwFc/+YsM+Gs1kabZ2DDse3mCIB1mPd8Y8qGV0UFDHHPZPIK pjLzR6cBGX4fKPnUt9PD9BeYXBxoGknUKCXwwDweinvM4NgiDy+aix73uAQGzB+ra3jh pPTMSnWhf0Q4U/UN6XDwO12xIAhZR9vprEsGyxFJQ3EoMBJ6cBDYDey3cA1D2QJ9sVew zs095Q0K8hPadMYHqmUQEoJj8Al4IGCfN72nF7LEaeo2jcxRkwYsn5lmYVeqUmxL9h9R 0X6A== X-Forwarded-Encrypted: i=1; AJvYcCVpQbIP2qrkhM6fu/awJ+Q4RQEXtCZZQ7CoZXbJ6qokHaSkf3yirsDBYU3zwKRMGy+EJsbCdH7YVNgqaJNAZF13ZSFu X-Gm-Message-State: AOJu0YzxfQ0t4FTNZrWVe52N79Na5kmCYXEOh3KIqYoaIC7lDvpQolgm UHS47tcg1n4buBa549Sjjof7NFveT+yVSP+DD8FrYuCzFcB2eMdlLoyxIg== X-Google-Smtp-Source: AGHT+IHwZRKqJeJZUr47oC5hcufP40Zq+GB3/8KypxJOu6o2+julfuPFygtjTyfO41m9UdnhpqXlFg== X-Received: by 2002:a50:d6dc:0:b0:57c:73a3:e1a9 with SMTP id 4fb4d7f45d1cf-57cbd8b9eb8mr1436892a12.30.1718351768455; Fri, 14 Jun 2024 00:56:08 -0700 (PDT) Original-Received: from pro2.fritz.box (pd9e367ea.dip0.t-ipconnect.de. [217.227.103.234]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-57cb741e96bsm1960234a12.76.2024.06.14.00.56.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Jun 2024 00:56:08 -0700 (PDT) In-Reply-To: ("Gerd =?utf-8?Q?M=C3=B6llman?= =?utf-8?Q?n=22's?= message of "Fri, 14 Jun 2024 09:30:31 +0200") Received-SPF: pass client-ip=2a00:1450:4864:20::52f; envelope-from=gerd.moellmann@gmail.com; helo=mail-ed1-x52f.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:320054 Archived-At: Gerd M=C3=B6llmann writes: > Eli Zaretskii writes: > >>> From: Gerd M=C3=B6llmann >>> Cc: Eli Zaretskii , emacs-devel@gnu.org >>> Date: Thu, 13 Jun 2024 21:37:41 +0200 >>>=20 >>> Maybe one could reserve + commit a suitable block upfront, maybe as one >>> big IGC_OBJ_PAD, and use read(2) or so to read the .pdmp into that >>> block. >> >> Wouldn't that slow down startup? pdumper uses memory-mapped files to >> make that as fast as possible, and for a good reason: at the time >> pdumper was introduced people objected to have startup slow down even >> by a few hundreds of milliseconds. > > I don't know. Did pdumper do many reads that were replaced with one > mmap? This one could do one large read instead of one mmap. Found this benchmarking code: https://github.com/david-slatinek/c-read-vs.-mmap It comes to the conclusion that, for 32MB files, mmap is 17% faster than a sequence of reads of 16Kb each (2000 calls). Hm.