From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 08AB61FF142 for ; Fri, 19 Jun 2026 13:01:40 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id F1E8BC344; Fri, 19 Jun 2026 13:01:37 +0200 (CEST) Message-ID: <7a2d0777-1fb4-4a87-99ed-2c77caa0082b@proxmox.com> Date: Fri, 19 Jun 2026 13:01:01 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH manager v3] fix #4503: ui: qemu: add detect zeroes disk option To: Lukas Sichert , pve-devel@lists.proxmox.com References: <20260618115005.45266-1-l.sichert@proxmox.com> Content-Language: en-US From: David Riley In-Reply-To: <20260618115005.45266-1-l.sichert@proxmox.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1781866856908 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.162 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 Message-ID-Hash: L3VQDBDQYYEHGYVPOHSIBLZRF7BNEMZQ X-Message-ID-Hash: L3VQDBDQYYEHGYVPOHSIBLZRF7BNEMZQ X-MailFrom: d.riley@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox VE development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On 6/18/26 1:49 PM, Lukas Sichert wrote: > When discard is enabled, qemu-server defaults to 'detect-zeroes=unmap'. > This can have a significant performance impact for zero writes on some > setups, while users might still want to keep guest discard/TRIM support > enabled. > > Allow configuring the option independently so 'discard' can stay enabled > while zero detection is disabled. Persist the checkbox state explicitly, > as the backend treats an absent value as default-enabled behavior, > resulting in 'detect-zeroes=unmap' when 'discard' is enabled. Thanks for submitting this patch. While it clearly addresses the performance issues reported in #4503 [0], I was reading through the Bugzilla thread and noticed a request to support the third QEMU state for detect_zeroes [1]. Currently, the underlying parameter supports off, on, and unmap [2]. Since we are already modifying this configuration in the UI, it might make sense to fully expose all three options to the user rather than just a binary toggle as there is a difference between "on" and "unmap". [0] https://bugzilla.proxmox.com/show_bug.cgi?id=4503 [1] https://bugzilla.proxmox.com/show_bug.cgi?id=4503#c8 [2] https://www.qemu.org/docs/master/interop/qemu-storage-daemon-qmp-ref.html#enum-QSD-block-core.BlockdevDetectZeroesOptions > Link: https://bugzilla.proxmox.com/show_bug.cgi?id=4503 > Signed-off-by: Lukas Sichert > --- > > Notes: > changes from v2 to v3 (thanks @Fabian): > - add a comment explaining why this property is handled differently from > the others > > changes from v1 to v2: > - added bug-numer to commit header > - appended bug-link to commit body > > www/manager6/qemu/HDEdit.js | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > [...] >