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 A7A63984B6 for ; Wed, 15 Nov 2023 09:51:41 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 804AF1CFE for ; Wed, 15 Nov 2023 09:51:41 +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, 15 Nov 2023 09:51:41 +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 CB23542EEF for ; Wed, 15 Nov 2023 09:51:40 +0100 (CET) Date: Wed, 15 Nov 2023 09:51:33 +0100 From: Fabian =?iso-8859-1?q?Gr=FCnbichler?= To: Proxmox VE development discussion References: <20231114140204.27679-1-f.ebner@proxmox.com> <20231114140204.27679-4-f.ebner@proxmox.com> <767911ec-7dee-443e-bb29-513d0c63a74a@proxmox.com> In-Reply-To: <767911ec-7dee-443e-bb29-513d0c63a74a@proxmox.com> MIME-Version: 1.0 User-Agent: astroid/0.16.0 (https://github.com/astroidmail/astroid) Message-Id: <1700038013.zqvp143ykl.astroid@yuna.none> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL 0.066 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: [pve-devel] [RFC common 2/2] fix #4501: next unused port: work around issue with too short expiretime X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Nov 2023 08:51:41 -0000 On November 14, 2023 3:13 pm, Fiona Ebner wrote: > Am 14.11.23 um 15:02 schrieb Fiona Ebner: >> For QEMU migration via TCP, there's a bit of time between port >> reservation and usage, because currently, the port needs to be >> reserved before doing a fork, where the systemd scope needs to be set >> up and swtpm might need to be started before the QEMU binary can be >> invoked and actually use the port. >>=20 >> To improve the situation, get the latest port recorded in the >> reservation file and start trying from the next port, wrapping around >> when hitting the end. Drastically reduces the chances to run into a >> conflict, because after a given port reservation, all other ports are >> tried first before returning to that port. >=20 > Sorry, this is not true. It can be that in the meantime, a port for a > different range is reserved and that will remove the reservation for the > port in the migration range if expired. So we'd need to change the code > to remove only reservations from the current range to not lose track of > the latest previously used migration port. the whole thing would also still be racy anyway across processes, right? not sure it's worth the additional effort compared to the other patches then.. if those are not enough (i.e., we still get real-world reports) then the "increase expiry further + explicit release" part could still be implemented as follow-up..