From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 1722AB8D34 for ; Wed, 6 Dec 2023 15:14:22 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id EC8BD2DC7 for ; Wed, 6 Dec 2023 15:14:21 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Wed, 6 Dec 2023 15:14:21 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 17FB3425EF for ; Wed, 6 Dec 2023 15:14:21 +0100 (CET) Date: Wed, 6 Dec 2023 15:14:20 +0100 (CET) From: =?UTF-8?Q?Fabian_Gr=C3=BCnbichler?= To: Gabriel Goller , Proxmox Backup Server development discussion Message-ID: <695531623.1949.1701872060137@webmail.proxmox.com> In-Reply-To: <2507e464-7b0a-4814-b089-dc5b1d8d2904@proxmox.com> References: <20231206132834.240700-1-g.goller@proxmox.com> <1764237283.1899.1701870086441@webmail.proxmox.com> <2507e464-7b0a-4814-b089-dc5b1d8d2904@proxmox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Priority: 3 Importance: Normal X-Mailer: Open-Xchange Mailer v7.10.6-Rev55 X-Originating-Client: open-xchange-appsuite X-SPAM-LEVEL: Spam detection results: 0 AWL 0.064 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_SCC_BODY_TEXT_LINE -0.01 - URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [proxmox.com] Subject: Re: [pbs-devel] [PATCH v2 proxmox{, -backup} 0/2] Move ProcessLocker to tmpfs X-BeenThere: pbs-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox Backup Server development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Dec 2023 14:14:22 -0000 > Gabriel Goller hat am 06.12.2023 14:56 CET geschri= eben: > On 12/6/23 14:41, Fabian Gr=C3=BCnbichler wrote: > >> > >> Gabriel Goller hat am 06.12.2023 14:28 CET=20 > >> geschrieben: This moves the `ProcessLocker`'s `.lock` file to=20 > >> `/run/proxmox-backup/locks` (tmpfs). The first patch only converts=20 > >> all the `F_SETLK` flags to `F_OFD_SETLK` flags. This changes normal=20 > >> locks, which are based on the process, to locks based on an open file= =20 > >> descriptor. This actually doesn't change anything, because we use=20 > >> mutexes, so the lock is already thread-safe. It would be cleaner=20 > >> though and would safe us from weird quirks like closing the lock-file= =20 > >> which would drop all the locks when using the POSIX `F_SETLK`. See=20 > >> more here [0]. > >> > > this might be moot, since most likely both patches go in at the same=20 > > time, is this change reload/upgrade-compatible? i.e., if an old=20 > > proxmox-backup(-proxy) process is (still) running that has the lock=20 > > open with F_SETLK, and the new one obtains it using F_OFD_SETLK, is=20 > > the behaviour still correct? (the other direction might be interesting= =20 > > too, but can only happen on an unsupported downgrade) > > > Just spoke with Stefan Sterz about this and we will probably=20 > apply/release this with a major version bump (kernel update), so that=20 > the user > is forced to reboot the system (same as with his tmpfs locking series). > I don't think there is another way, because the lockfiles get moved to=20 > another dir. Although F_SETLK and F_OFD_SETLK should be compatible, > so having one process use F_SETLK and another F_OFD_SETLK *should* still= =20 > work (don't take my word for it though). that doesn't really help though, unless we also add machinery to detect the= missing reboot and block any process-locker-requiring stuff in the new pro= cess until it has happened? or we make "set all datastores to read-only or = offline" a requirement for upgrading from 3 to 4, instead of optional like = for 2 to 3[0]. otherwise even just the time between "postinst of PBS packag= e is called" to "upgrade of whole system is fully done" can be big enough t= o cause a problem.. 0: https://pbs.proxmox.com/wiki/index.php/Upgrade_from_2_to_3#Optional:_Ena= ble_Maintenance_Mode