From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate001.proxmox.com (gate001.proxmox.com [IPv6:2a0f:8001:1:32::40]) by lore.proxmox.com (Postfix) with ESMTPS id 56B151FF146 for ; Tue, 07 Jul 2026 23:53:42 +0200 (CEST) Received: from gate001.proxmox.com (localhost.localdomain [127.0.0.1]) by gate001.proxmox.com (Proxmox) with ESMTP id 7EAF92141B; Tue, 07 Jul 2026 23:53:41 +0200 (CEST) Message-ID: <5b842f53-3059-4ac2-9e7a-4a7a04132ace@proxmox.com> Date: Tue, 7 Jul 2026 23:53:04 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Beta Subject: Re: [PATCH datacenter-manager 2/3] ui: d/rules: use thin instead of fat LTO To: =?UTF-8?Q?Fabian_Gr=C3=BCnbichler?= , Dominik Csapak , pdm-devel@lists.proxmox.com References: <20260706114822.2751086-1-d.csapak@proxmox.com> <20260706114822.2751086-3-d.csapak@proxmox.com> <1783433095.x62omid41h.astroid@yuna.none> Content-Language: en-US From: Thomas Lamprecht In-Reply-To: <1783433095.x62omid41h.astroid@yuna.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1783461176669 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.015 Adjusted score from AWL reputation of From: address DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment (newer systems) 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: ALAOFR5AS3K4UJBC7TN6ZVKK4W4SOPUC X-Message-ID-Hash: ALAOFR5AS3K4UJBC7TN6ZVKK4W4SOPUC X-MailFrom: t.lamprecht@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 Datacenter Manager development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Am 07.07.26 um 16:06 schrieb Fabian Grünbichler: > On July 6, 2026 1:44 pm, Dominik Csapak wrote: >> fat LTO merges all LLVM modules into a single unit for optimizing. >> Changing this to thin LTO increases the uncompressed binary size by 1.59 >> MiB (+11%) (compressed +192KiB/+4.6%) but save us ~160s (-40%) of (wall) >> build time during a 'make deb'. > but what are the effects on runtime performance? the same question also > applies to the next patch, a single codegen unit increases the amount of > optimizations the compiler can do.. FWIW, https://docs.wasmtime.dev/examples-minimal.html states: """ Note that with LTO using a single codegen unit may only have marginal benefit. If not using LTO, however, a single codegen unit will likely provide benefit over the default 16 codegen units. """ If that (still) holds, we currently do the worst of both worlds compile time wise while not really profiting from this. I'd probably try dropping overriding codegen units first (we do not lower that on performance other (non-wasm) critical code either, e.g. PBS.