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 4E72462B58 for ; Mon, 21 Dec 2020 16:49:25 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 4600C22FB3 for ; Mon, 21 Dec 2020 16:49:25 +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 8918622FA6 for ; Mon, 21 Dec 2020 16:49:24 +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 4B56745392 for ; Mon, 21 Dec 2020 16:49:24 +0100 (CET) To: Dietmar Maurer , Proxmox Backup Server development discussion References: <20201221135611.14456-1-s.reiter@proxmox.com> <1412279965.2136.1608565017552@webmail.proxmox.com> From: Stefan Reiter Message-ID: <5c0cbe82-1cd1-aeae-6363-097ca054506f@proxmox.com> Date: Mon, 21 Dec 2020 16:49:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <1412279965.2136.1608565017552@webmail.proxmox.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 1.616 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 -3.299 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] [RFC 0/2] backup client: implement some HTTP timeouts 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: Mon, 21 Dec 2020 15:49:25 -0000 On 12/21/20 4:36 PM, Dietmar Maurer wrote: >> Not a comprehensive overhaul, but should fix the most common hangs to at least >> finish *sometime*. > > We already have TCP timeouts. So why exactly do we need those short timeouts? > It's not a TCP timeout if the server hangs. This prevents the case where the client has a connection established but the server fails to send data within the given time. Came up during discussion of this report: https://forum.proxmox.com/threads/qmp-command-backup-failed-got-timeout.77749/#post-357700 where high load on the server (from too many verification tasks, which is a different problem) causes VM clients to hang for unreasonable amounts of time. (Note that with QEMU 5.2 we can easily do the 'connect' async in the background as well, preventing the full VM to hang, but we still need some way to timeout the connection attempt, lest it stays active in the background)