From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp10.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms9.migadu.com with LMTPS id gDnIBZ+Dk2TxWgAASxT56A (envelope-from ) for ; Thu, 22 Jun 2023 01:11:27 +0200 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp10.migadu.com with LMTPS id 4JL7BJ+Dk2Tw2wAAG6o9tA (envelope-from ) for ; Thu, 22 Jun 2023 01:11:27 +0200 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id A3E06364A4 for ; Thu, 22 Jun 2023 01:11:26 +0200 (CEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qC6yR-0001VX-PF; Wed, 21 Jun 2023 19:10:51 -0400 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 1qC6yP-0001VK-PK for guix-devel@gnu.org; Wed, 21 Jun 2023 19:10:49 -0400 Received: from mx1.riseup.net ([198.252.153.129]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qC6yN-0005lQ-R2 for guix-devel@gnu.org; Wed, 21 Jun 2023 19:10:49 -0400 Received: from fews01-sea.riseup.net (fews01-sea-pn.riseup.net [10.0.1.109]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx1.riseup.net (Postfix) with ESMTPS id 4QmfPG438bzDrC5; Wed, 21 Jun 2023 23:10:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=riseup.net; s=squak; t=1687389042; bh=F6yNY1P2WpwDfXfnGWnyoyazbj7zq9U8vGA/92VB3DA=; h=References:From:To:Cc:Subject:Date:In-reply-to:From; b=rKku1egxIQ/gYuz+Jbyg1f7Pcqd8RHW8sMDSuxF17CVu7BpBqr7qLPyc3AS8Fe1hm yRHgCnnvKUMrjJ5FpoJqLeQVXO/9vhOEyfqrfpryiVoXnMmR5Hh7p7Z3mLGvGijame 0OHNxGnhF0jzf/mZv4qAJMmCpYbvAAvRKrMeBl0M= X-Riseup-User-ID: 700B769FBF69ABEA227A382CD88969D3D099BC5AD77A2E247E97D170A4F5A1D2 Received: from [127.0.0.1] (localhost [127.0.0.1]) by fews01-sea.riseup.net (Postfix) with ESMTPSA id 4QmfPF66ZKzJp9r; Wed, 21 Jun 2023 23:10:41 +0000 (UTC) References: <87jzvxoicg.fsf@riseup.net> From: Csepp To: Csepp Cc: guix-devel@gnu.org, pukkamustard Subject: Re: distributed substitutes: file slicing Date: Thu, 22 Jun 2023 01:06:50 +0200 In-reply-to: <87jzvxoicg.fsf@riseup.net> Message-ID: <87zg4sl8d8.fsf@riseup.net> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=198.252.153.129; envelope-from=raingloom@riseup.net; helo=mx1.riseup.net X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-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: guix-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: guix-devel-bounces+larch=yhetil.org@gnu.org X-Migadu-Country: US X-Migadu-Flow: FLOW_IN ARC-Seal: i=1; s=key1; d=yhetil.org; t=1687389086; a=rsa-sha256; cv=none; b=kK+0QbUDEXhlo+Qi5YwwlwDVkhF0R41OsgqAuUCqd1Hs0onQeP1V1eJx9wDEEQhT3J/kbj q75nDlP/Arfhrr60mrIOEe3VuNIGWpu4qXepOMQKyjqWfRmvIoGoY3MGSAuTnqE85YjVW0 /tIwSfJZtYBwaSkWX3SqZOtn5A/fIDH00aTcl4mkUtL1nnR73D5DsMQuGoePhfsEbT5qHK R4HNIusfwuM8Jzpu7K2si5pzadgAwJHr0PU1pLL+6g65Q26bl4zV9KwYHKjM463m8MujcB rLM4uB1TgqMxq0H/VF2EoiRrQGsLgh9nWg1ru/+7gdpcWScCcJeA0gcq1bna9w== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=riseup.net header.s=squak header.b=rKku1egx; dmarc=pass (policy=none) header.from=riseup.net; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1687389086; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post:dkim-signature; bh=F6yNY1P2WpwDfXfnGWnyoyazbj7zq9U8vGA/92VB3DA=; b=t6UNefZZ24uB2do3D/zVVy7K6wU2JXeh9K2932Yd3PE5gXSd5REMgZUZqO/DZoU7rsQ6hG 1IsxVaoYD9EnU0uReW8WWidNxhLqoew8lcji5Ft0/Q1SRUkvSY74lUhnngkdnNSN4y/qPG YY1VHsY7xHRAd6ivZleY5S0QIYuiJxf/CxykdyIhwm+fEuD6tu7pS8+RP2m0QA+3taNAvA syY/UHMRHgNSzZDDFQ1W2cf5cmqLtrDnvvGybHJuwr1RcEPx3WbXPgp6exV/4PmxQK1lsZ Qv/IAmaR0/djr0Wo7BZ29cCg6v0jF/Tw8DiYb0pzKk5Q94QLPyUJKF/kYXHvCQ== Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=riseup.net header.s=squak header.b=rKku1egx; dmarc=pass (policy=none) header.from=riseup.net; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Scanner: scn0.migadu.com X-Migadu-Spam-Score: -10.39 X-Spam-Score: -10.39 X-Migadu-Queue-Id: A3E06364A4 X-TUID: Wlt2RRU04tml Csepp writes: > I have a question / suggestion about the distributed substitutes > project: would downloads be split into uniformly sized chunks or could > the sizes vary? > Specifically, in an extreme case where an update introduced a single > extra byte at the beginning of a file, would that result in completely > new chunks? > > An alternative I've been thinking about is this: > find the store references in a file and split it along these references, > optionally apply further chunking to the non-reference blobs. > > It's probably best to do this at the NAR level?? > > Storing reference offsets is already something that we should be doing to > speed other operations up, so this could tie in nicely with that. I was sent this link that others might find interesting: https://alternativebit.fr/posts/nixos/future-of-nix-substitution/