From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp2 ([2001:41d0:2:bcc0::]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) by ms0.migadu.com with LMTPS id GBJlNH7ufWC1gAAAgWs5BA (envelope-from ) for ; Mon, 19 Apr 2021 22:56:30 +0200 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp2 with LMTPS id KOD5L37ufWD3VAAAB5/wlQ (envelope-from ) for ; Mon, 19 Apr 2021 20:56:30 +0000 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 63461FF60 for ; Mon, 19 Apr 2021 22:56:30 +0200 (CEST) Received: from localhost ([::1]:53912 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lYawX-0001Le-0g for larch@yhetil.org; Mon, 19 Apr 2021 16:56:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40890) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lYavv-0001JE-Vt for guix-devel@gnu.org; Mon, 19 Apr 2021 16:55:52 -0400 Received: from mira.cbaines.net ([212.71.252.8]:57654) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lYavt-00085S-OD for guix-devel@gnu.org; Mon, 19 Apr 2021 16:55:51 -0400 Received: from localhost (unknown [IPv6:2a02:8010:68c1:0:8ac0:b4c7:f5c8:7caa]) by mira.cbaines.net (Postfix) with ESMTPSA id 835F427BC6C for ; Mon, 19 Apr 2021 21:55:47 +0100 (BST) Received: from capella (localhost [127.0.0.1]) by localhost (OpenSMTPD) with ESMTP id bf760ed6 for ; Mon, 19 Apr 2021 20:55:47 +0000 (UTC) References: <87mtvhnsn6.fsf@cbaines.net> User-agent: mu4e 1.4.15; emacs 27.1 From: Christopher Baines To: guix-devel@gnu.org Subject: Re: Narinfo negative and transient error caching In-reply-to: <87mtvhnsn6.fsf@cbaines.net> Date: Mon, 19 Apr 2021 21:55:47 +0100 Message-ID: <87h7k2hu3w.fsf@cbaines.net> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Received-SPF: pass client-ip=212.71.252.8; envelope-from=mail@cbaines.net; helo=mira.cbaines.net X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.23 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" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1618865790; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to: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; bh=flHnXImi/Qfa9VaO5SR7p8eSLY0zjZ02LuhtstcwW/k=; b=FnXejTv533zCAQahqR8cN8O2OE/HyfrRlupxs13rCa28BYpmkdYjb+445A6Nbbx0Fqlrw1 Zbn98EHYiePOOmkxDuBLu1EgG329C7xhi3v4C1z4wLtQSjv1GH2qHoaj+2Po6reXRau5hM LJVUuJazh6DtZ1udOCjC42L6T/zc7dQudiT26ov5cH+em8A3c6wYneEGI3udowrojgqUNB y6sHuHFBz2XacPIC5K7a5v+fDONiOb7w3eR2+ofOfcxA55qO3iKa/zZkFWJZmsihJWKZBx 0u/8BOi6KkzANGBA5C1nOGs0z39hn2TLw5qNLUpU6PDBKeH/5R28uO4SB8J0sw== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1618865790; a=rsa-sha256; cv=none; b=M8OKj74jTVeO5KV5pMO3gOpq9iEJGJQEEoOPi6ku1UiuSI10/ygiP6YgTKX85HbAHKr5CJ napXm5jXCn6if5b8xv7lEyvtYrlop+dzwu22LmKqmHp96pFTXWhdZTB18dKqwFliGs67ct rwHJGr2cWHkL5YMa9WBsosQBGoMJ63Ae0MA94uH9b9pM6ir+KaEnRl8Ke5KObIu5ieYCQv 5mD5C0WkUIXJDzB06QY24Z37UeZBeyxLUvy5XfILC0WDh8unKP1cqWryyp+s/M0uTw1mr8 F9KqwacLjp0gucldpvPwLgBt+2BB5BGB5RcxUxIH0egPErNVX9Hk+Ybh6W9PEg== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of guix-devel-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-devel-bounces@gnu.org X-Migadu-Spam-Score: -3.04 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of guix-devel-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-devel-bounces@gnu.org X-Migadu-Queue-Id: 63461FF60 X-Spam-Score: -3.04 X-Migadu-Scanner: scn0.migadu.com X-TUID: PXCJocG8YtHg --=-=-= Content-Type: text/plain Christopher Baines writes: > This has been on my mind for a while, as I wonder what effect it has on > users fetching substitues. > > The narinfo caching as I understand it works as follows: > > Default success TTL => 36 hours > Negative TTL => 1 hour > Transient error TTL => 10 minutes > > I'm ignoring the success TTL, I'm just interested in the negative and > transient error values. Negative means that when a server says it > doesn't have an output, that response will be cached for an > hour. Transient errors are for other HTTP response codes, like 504. > > I had a look through the Git history, caching negative lookups has been > a thing for a while. Caching transient errors was added, but I couldn't > see why. > > Personally I don't see a reason to keep either behaviours? I've now sent a patch to remove this behaviour: https://issues.guix.gnu.org/47897 --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQKlBAEBCgCPFiEEPonu50WOcg2XVOCyXiijOwuE9XcFAmB97lNfFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldDNF ODlFRUU3NDU4RTcyMEQ5NzU0RTBCMjVFMjhBMzNCMEI4NEY1NzcRHG1haWxAY2Jh aW5lcy5uZXQACgkQXiijOwuE9XdNYw//YmtMk1dmUdRZLfUSIMMYMIV73uVeILhj zr+QUlJ/nrQfRkANCKfDu87xbeD+UUcpqku3EpMG8fdqxxrO4pz2mSLehacvjrya QMXyQk0IkkuiLzP3gTnvS2+gRh4216SbL0Osn7EtQ/DERQzgzxuStxUAajcRRY9o 6oG8zv4k/6uNnnpTVUcNpYF8ADIPB1jkZ7W3MPEsm/gLPpq/EnQe6RR+n7fjW8+V Egise6T4Zikf8Tqt2USe3IB0weJLF3yyL/4B0XTn4cyfu4mv0AAIn+xPF23Pq/Cy uwBVBgd89n5RbOtmUHNqYg6SOxyMxDxbhzaC0pi70lT6p0vkD0bM2EspzajVJRee nKPsRGjHn7eUTVGNjKsbcxaMCo+DzDCMOiR8pC4clkrHu1Bowi45JfucdYQuQrjf tzBL/k8140G7mExBvljoaJZfFJkQF9WFvpPY8o6fxr5/6O4DU7JrHySqd6Qm0ioH 7Tr4XyQZQqP4JAcX15UM34N7iAWwci2jMFQmqmuIPlp12lXtUVXQwoNEEnylXtEX pl89ai6i3i9PYNd9QxHB2DDrB8WNl00Xw4YFS82KyMiqOoYLBE3t0qmRHixLKRyB 9EQFf/YcukwlaGLqme0PjSl+lEJ1vz29/le05on6NrxaJsAfw4GMMU6cuGxVcfXS GZs/tdAY4Oc= =yLu1 -----END PGP SIGNATURE----- --=-=-=--