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 02E40646C7 for ; Fri, 30 Oct 2020 12:10:11 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id E418F12C5D for ; Fri, 30 Oct 2020 12:09:40 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (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 id 781A112C52 for ; Fri, 30 Oct 2020 12:09:40 +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 3AFE445F8B; Fri, 30 Oct 2020 12:09:40 +0100 (CET) To: Proxmox Backup Server development discussion , Graeme Seaton References: <215c8b24-84f6-c244-f3d0-347390001707@graemes.com> From: Thomas Lamprecht Message-ID: Date: Fri, 30 Oct 2020 12:09:39 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:83.0) Gecko/20100101 Thunderbird/83.0 MIME-Version: 1.0 In-Reply-To: <215c8b24-84f6-c244-f3d0-347390001707@graemes.com> Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL 0.006 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.261 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pbs-devel] Verify, Prune & GC sequence 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: Fri, 30 Oct 2020 11:10:11 -0000 Hi, On 30.10.20 10:31, Graeme Seaton wrote: > If I have verify, prune & GC all set to run daily do the jobs run concu= rrently or in sequence? Well, you could just try out ;-) But yes, they can run in parallel.=20 Since PBS allows multiple potentially interfering operations at the same = time (e.g., garbage collect, prune, multiple backup creations (only in separate groups), forget, ...),= these need to lock against each other in certain scenarios. There is no overarching global lock thou= gh, instead always the finest grained lock possible is used, because running these operations concurren= tly is treated as a feature on its own. Still, while we handle locking fine grained an admin could try to optimiz= e the order of scheduling such things. 1. Prune, to increase the chance that GC can sweep more data and verify h= as less to look at. This is rather quick, so one could schedule the next probably half an = hour afterwards and be confident it finishes before 2. 2. GC, as chunks are deleted, which may make verify also faster as it can= make the underlying FS faster - but that's rather theory. 3. Verify I think the order of 2. and 3. is not to important, but personally, I'd a= lways schedule pruning first, can only help. cheers, Thomas