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 8E5E1B8D23 for ; Wed, 6 Dec 2023 14:56:57 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 686D22B50 for ; Wed, 6 Dec 2023 14:56:27 +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 14:56:26 +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 93D58425CF for ; Wed, 6 Dec 2023 14:56:26 +0100 (CET) Message-ID: <2507e464-7b0a-4814-b089-dc5b1d8d2904@proxmox.com> Date: Wed, 6 Dec 2023 14:56:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: =?UTF-8?Q?Fabian_Gr=C3=BCnbichler?= , Proxmox Backup Server development discussion References: <20231206132834.240700-1-g.goller@proxmox.com> <1764237283.1899.1701870086441@webmail.proxmox.com> From: Gabriel Goller In-Reply-To: <1764237283.1899.1701870086441@webmail.proxmox.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.156 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 - 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 13:56:57 -0000 On 12/6/23 14:41, Fabian Grünbichler wrote: >> >> Gabriel Goller hat am 06.12.2023 14:28 CET >> geschrieben: This moves the `ProcessLocker`'s `.lock` file to >> `/run/proxmox-backup/locks` (tmpfs). The first patch only converts >> all the `F_SETLK` flags to `F_OFD_SETLK` flags. This changes normal >> locks, which are based on the process, to locks based on an open file >> descriptor. This actually doesn't change anything, because we use >> mutexes, so the lock is already thread-safe. It would be cleaner >> though and would safe us from weird quirks like closing the lock-file >> which would drop all the locks when using the POSIX `F_SETLK`. See >> more here [0]. >> > this might be moot, since most likely both patches go in at the same > time, is this change reload/upgrade-compatible? i.e., if an old > proxmox-backup(-proxy) process is (still) running that has the lock > open with F_SETLK, and the new one obtains it using F_OFD_SETLK, is > the behaviour still correct? (the other direction might be interesting > too, but can only happen on an unsupported downgrade) > Just spoke with Stefan Sterz about this and we will probably apply/release this with a major version bump (kernel update), so that 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 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 work (don't take my word for it though).