From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp0 ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms0.migadu.com with LMTPS id UMpnAIZQnmCBQgAAgWs5BA (envelope-from ) for ; Fri, 14 May 2021 12:27:18 +0200 Received: from aspmx1.migadu.com ([2001:41d0:8:6d80::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp0 with LMTPS id ePe8N4VQnmCiZQAA1q6Kng (envelope-from ) for ; Fri, 14 May 2021 10:27:17 +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 857A325986 for ; Fri, 14 May 2021 12:27:17 +0200 (CEST) Received: from localhost ([::1]:52936 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lhV2K-0005Iq-BI for larch@yhetil.org; Fri, 14 May 2021 06:27:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:32824) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lhUwn-00076l-Po for guix-devel@gnu.org; Fri, 14 May 2021 06:21:33 -0400 Received: from sender4-of-o51.zoho.com ([136.143.188.51]:21187) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lhUwj-0006YU-Oe for guix-devel@gnu.org; Fri, 14 May 2021 06:21:33 -0400 ARC-Seal: i=1; a=rsa-sha256; t=1620987683; cv=none; d=zohomail.com; s=zohoarc; b=OxtIMvDRjna4FA4+C3NnsrwoSNOy1h8rG/ngsyOlTYFAPJU4VCHjlDXhB/sliW/5SaVFYrLiOYTyyTPBewNv5/mwexZbbzulyx8yFlg8lE2Hzrfjz3CO/laQvIaZFuqIC+OmtUPxCc8Af/2vN8uyBMCOeV+uEe2sT5Mgwv67l1s= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1620987683; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:To; bh=wu/Mn4fE7UfLo2W1LCkwmztH/jucIOFL40jXt8WPyYM=; b=b9W4rcqzB5Fefh2bun4moF0fY/3DG9WTjacdJNJ1mXQgz7M3jZAfHPqS8PUE+zpjqFtjEB3bvFbMVOMemjL7tZTLfx1q5WtXWSaRBsZi5zD16QVk/mN5qY4T+/pF5idOHMZyXh326urB9jf3ngoP1xJs4eiZ2mAOxaNg0+3bG/8= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=elephly.net; spf=pass smtp.mailfrom=rekado@elephly.net; dmarc=pass header.from= header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1620987683; s=zoho; d=elephly.net; i=rekado@elephly.net; h=References:From:To:Cc:Subject:In-reply-to:Date:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding; bh=wu/Mn4fE7UfLo2W1LCkwmztH/jucIOFL40jXt8WPyYM=; b=fPluuOsMmFs/EIFFoz2EeTZdrBPvjb8T3rJZI6Gal+lTSvOtvaDnzj+JEUKC1cPA eN0xvUJbWZIwVEvw9C8pUDuEe773RDiaPMnvWcGroRQj5ZkDmC+Oo5/gcid3KAPpeFN MVreTvaxZ6Qm0MOuoHjSlL3QDG+dVf77U4Wk9z00= Received: from localhost (p54ad40a8.dip0.t-ipconnect.de [84.173.64.168]) by mx.zohomail.com with SMTPS id 162098768047415.344908623017659; Fri, 14 May 2021 03:21:20 -0700 (PDT) References: <87im3qq57z.fsf@elephly.net> <8735utvvtu.fsf@gnu.org> User-agent: mu4e 1.4.15; emacs 27.2 From: Ricardo Wurmus To: Ludovic =?utf-8?Q?Court=C3=A8s?= Subject: Re: =?utf-8?B?4oCcZ3VpeCBnY+KAnSw=?= auto gcroots, cluster deployments In-reply-to: <8735utvvtu.fsf@gnu.org> X-URL: https://elephly.net X-PGP-Key: https://elephly.net/rekado.pubkey X-PGP-Fingerprint: BCA6 89B6 3655 3801 C3C6 2150 197A 5888 235F ACAC Date: Fri, 14 May 2021 12:21:16 +0200 Message-ID: <8735uplioz.fsf@elephly.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Received-SPF: pass client-ip=136.143.188.51; envelope-from=rekado@elephly.net; helo=sender4-of-o51.zoho.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, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=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: , Cc: guix-devel@gnu.org Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1620988037; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post:dkim-signature; bh=wu/Mn4fE7UfLo2W1LCkwmztH/jucIOFL40jXt8WPyYM=; b=IDIbNcURmNGbBH+lMbGOPwwS4xZX+W00X0J+V6Eper4jx5/JpfjKkfj2zffY0h60OGMxX4 yZAoaehnR6v74hj4XDUy3tJ+KRr2KJCAZgCHFxk8GeBT/zNURbFTAH9/IVjVlHKT/nFimk gx4zVt372f96Cn9E0to9XR1heSdaK+WU0Dce/TSWmj0/sKLYDOIZuEYD6KmE0cqGN4j449 ebpIHj6A8M4XAxxoOj8sFS1X3fl3oSzibnx+3dWid8uOcQqYMm/MUo+BiP/Voh+1CyGdvl LQFIip1Ezl+/KsYZBY0KHSTHLvU+A/jMS5Y39WSJIgEGxhmVjcvPr4mtH4cq9A== ARC-Seal: i=2; s=key1; d=yhetil.org; t=1620988037; a=rsa-sha256; cv=pass; b=hf9oNXYYK4aKSxqqYQmbyT4tpFN2FRyTxPAWIhjNQDntS105qEzcgeOagF8nWqZovB1eLa ifHnZJtOF3D4n1xasFKnWn5w7jAH4h73mA1Oz5016HfLZloCn29QnDtz7LdIkhZS2v6OO8 Eo7SGMXrQ7C6YdBDvDVR5/EgSpCWE1bFI6OubXcfH4aqE47rIg1aTboHq8lBLRjGWFP8eU cKI+SZYTzcXlrNQtanJlo+1YUCvcifPkZXSnjSx5DDfwUCOLtUQXre3k7dMrkMK4RJ7uXg M9msTdg41JCltN3obkZms/BXF4sW2sU/b5bh7YcKYK+88u8BRqDMZqYyTZOqrg== ARC-Authentication-Results: i=2; aspmx1.migadu.com; dkim=pass header.d=elephly.net header.s=zoho header.b=fPluuOsM; arc=pass ("zohomail.com:s=zohoarc:i=1"); 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: -3.66 Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=elephly.net header.s=zoho header.b=fPluuOsM; arc=pass ("zohomail.com:s=zohoarc:i=1"); 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: 857A325986 X-Spam-Score: -3.66 X-Migadu-Scanner: scn0.migadu.com X-TUID: 8/EpkQQeJUAE Ludovic Court=C3=A8s writes: > Hi! > > Ricardo Wurmus skribis: > >> There are two problems here: >> >> 1) I don=E2=80=99t think =E2=80=9Cguix gc --list-dead=E2=80=9D (or =E2= =80=9C--list-live=E2=80=9D, or=20 >> more >> generally =E2=80=9CfindRoots=E2=80=9D in nix/libstore/gc.cc) should dele= te=20 >> anything. It should just list and not clean up. > > Maybe =E2=80=98findRoots=E2=80=99 could populate the list of stale roots = and=20 > it=E2=80=99d be up > to the caller to decide whether to delete them or not? Yes, this would be better. It already does this for links whose=20 targets exist but cannot be read. >> 2) For cluster installations with remote file systems perhaps=20 >> there=E2=80=99s >> something else we can do to record gcroots. We now have this >> excursion into unreadable space because we use a symlink, but=20 >> the >> start ($localstatedir/gcroots/auto) and endpoints=20 >> (/gnu/store/=E2=80=A6) are >> both accessible by the daemon. Since these intermediate=20 >> locations are >> tied to user accounts, could we not store them in a per-user >> directory? >> >> This problem does not exist for user profiles, because the link=20 >> in >> unreadable home directories is not all that important; it=20 >> merely=20 >> points to $localstatedir, which is always readable by the >> daemon. Perhaps we could do the same for temporary roots and=20 >> let >> *users* decide when to let go of them by giving them a command=20 >> to >> erase the important links in $localstatedir. >> >> So instead of having a link from >> /gnu/var/guix/gcroots/auto/8ypp8dmwnydgbsgjcms2wyb32mng0wri to=20 >> /home/me/projects/mrg1_chipseq/.guix-profile-1-link pointing to >> /gnu/store/ap0vrfxjdj57iqdapg8q83l4f7aylqzm-profile, we would=20 >> record >> /var/guix/profiles/per-user/me/auto/8ypp8dmwnydgbsgjcms2wyb32mng0wri=20 >> pointing to=20 >> /gnu/store/ap0vrfxjdj57iqdapg8q83l4f7aylqzm-profile, and >> then point /home/me/projects/mrg1_chipseq/.guix-profile-1-link=20 >> at >> that. Yes, removing >> /home/me/projects/mrg1_chipseq/.guix-profile-1-link would no=20 >> longer free up the profile for garbage collection, but removing >> $(readlink /home/me/projects/mrg1_chipseq/.guix-profile-1-link)=20 >> would. > > Yes, but how would per-user/me/auto/* be cleaned up? Yeah, that=E2=80=99s an open question. I get the appeal of having these things be cleaned up=20 automatically when the link disappears, but if we added this extra=20 layer of indirection for cluster deployments this would become=20 manual. Can we make this configurable perhaps=E2=80=A6? On my cluster=20 installation I=E2=80=99d rather have a cron job to erase the stuff in=20 per-user/me/auto/* on my own terms, than to have =E2=80=9Cguix gc=E2=80=9D = fail to=20 resolve links and consider it all garbage. --=20 Ricardo