From nobody Tue May 23 13:30:07 2023 X-Original-To: freebsd-arch@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QQZtq6c1rz4CT6n for ; Tue, 23 May 2023 13:30:11 +0000 (UTC) (envelope-from markjdb@gmail.com) Received: from mail-io1-xd32.google.com (mail-io1-xd32.google.com [IPv6:2607:f8b0:4864:20::d32]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1D4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QQZtq6CYGz3vp9 for ; Tue, 23 May 2023 13:30:11 +0000 (UTC) (envelope-from markjdb@gmail.com) Authentication-Results: mx1.freebsd.org; none Received: by mail-io1-xd32.google.com with SMTP id ca18e2360f4ac-76efc56e1cfso329247239f.1 for ; Tue, 23 May 2023 06:30:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684848611; x=1687440611; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=orpJsBqSJBRwAc4lJdUYSzYvljaJ5Bzp9d/wPMRo64k=; b=liR8OJEwHs0Ge59dthDxKsjq4fN5dT+oal7/Oa2jdZ5PHRzk0rn+EXvFXZ99BEf0WY 7Y+d0ntx661B8SxB7TX3PoZprr8I6Zn2Ox3FvpPY9WVXOdUqkuvkMv5IayGMZWPdQvx3 leKvDNUQYzvspzmwA4vN3MzLZ8nX7EdyDPH20Vm9rmuqj8D+UuPZyFlqwBivVwBmpnFG iRB9qfliAdr+k7mgl6WIeSilRL0TRy2OrVUjwzvPSLlcoTYc7XRwvZuo3MiTA5O0lGeY QPtNbZya6or/IfVZouhntsqaTyoLWBzH/y4AKvdfzOLdvTXodH8Ejd76l76RVC2b6Y9f u8mA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684848611; x=1687440611; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=orpJsBqSJBRwAc4lJdUYSzYvljaJ5Bzp9d/wPMRo64k=; b=F+fs/7zkZo2QDbSwJy2iqtOFSo1Ika4AzMtkrMm09UFfyewNwuhocKj3qGMkPUDunn 8/4DnNhF932o+MJuyP5Bm9MWpA/4NhQ0gxHKHoC1UTpfJJoDlz7NzqxRUq3tgIWB9Ej2 d0NdBK+QXFM0MdUyCHz6zcsyH6+UloFI0zNREh7sqg8XNZ/FQ/irLZ1akYqYfm8Bou3r HbTzUOBoPYWNIUmUsOHffJah/XhVQXosxpqci7QXvQpEYiTOE+2KcAyt5wud/SVPn83v GiJ2Ox4+dPfYMimj3Eg7NljeZo+JzN32iNtF9Z1qzNRKcEFyAMVRQ0y3OkK1/BFDheVi /sZA== X-Gm-Message-State: AC+VfDxkbkjwKtGYf9yk/Eb/PaVOvPHvENY4eQPfYXZNIcL1Y9M3tRgw ngZd4/jXiZWn+A5mbP+1vLo= X-Google-Smtp-Source: ACHHUZ5rIazrOQjKKQzGDtFbQj/Ohc/YJn2F2x+O0OpQHrhaaR9onnPaK9vQtmn2BWrwZXxH6yjdbA== X-Received: by 2002:a92:cb4f:0:b0:325:eb13:1045 with SMTP id f15-20020a92cb4f000000b00325eb131045mr9444190ilq.2.1684848610792; Tue, 23 May 2023 06:30:10 -0700 (PDT) Received: from nuc (192-0-220-237.cpe.teksavvy.com. [192.0.220.237]) by smtp.gmail.com with ESMTPSA id t15-20020a92dc0f000000b003317ebbc426sm2399686iln.47.2023.05.23.06.30.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 May 2023 06:30:09 -0700 (PDT) Date: Tue, 23 May 2023 09:30:07 -0400 From: Mark Johnston To: Hans Petter Selasky Cc: Warner Losh , Konstantin Belousov , "freebsd-arch@freebsd.org" Subject: Re: [RFC] An idea for general kernel post-processing automation in FreeBSD Message-ID: References: <394775eb-1000-60d9-2ddd-5c2aca6c99ea@selasky.org> <08ba506f-66c5-35eb-e992-ecf9dfeccf93@selasky.org> List-Id: Discussion related to FreeBSD architecture List-Archive: https://lists.freebsd.org/archives/freebsd-arch List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-arch@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <08ba506f-66c5-35eb-e992-ecf9dfeccf93@selasky.org> X-Rspamd-Queue-Id: 4QQZtq6CYGz3vp9 X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N On Tue, May 23, 2023 at 08:00:53AM +0200, Hans Petter Selasky wrote: > Hi Warner, > > When you make systems and use them, you get bound by them. If a system makes > a certain solution advantageous, it gets chosen, independent if it is a good > solution or not. > > The reason for our disagreement is simply this: > > You are thinking like a politican and want to be popular in the current > system of FreeBSD. > > I'm thinking like a mathematican regardless of what makes me popular in the > current system of FreeBSD. > > > Why not state that from the start? Implementing Quick Sort in qsort() and > using that everywhere is a political decision. > > This is not a technical fight, it is a political fight. I don't agree. From my point of view, Warner's position is the pragmatic one. We have perhaps 2% Linux's number of active developers[*], but we are relatively much larger in terms of performance, code complexity, size, etc.. Layering and simplicity of design are some of the main tools we have to counteract this imbalance. It helps reduce the amount of time developers spend on bugs that aren't directly related to what they are doing. It helps us think about and predict the behaviour of the system using only intuition. This tradeoff can mean that we do not provide the best possible performance in all cases, but that's often a reasonable tradeoff in this rather non-mathematical world where we do not have infinite resources. The existing SYSINIT bubblesort is a good example of this tradeoff. At the time it was written, it made sense to choose a simple, "good enough" solution and move on. Even now, this simple solution just works and is perfectly acceptable on the vast majority of systems where FreeBSD is deployed. I see this attitude reflected in Warner's and others' replies, and I agree with it. I suspect that Warner, rather than wanting to be popular per se, is replying in his own self-interest, which is to spend zero time debugging anything that might break if we start doing extra work at compile time to sort linker sets. It could be that some specific use-case will make your proposal more attractive. I don't mean to suggest that the topic should be closed forever. So far though, having read the thread and D40193, I'm not really sold. [*] I'm sure this number can vary wildly depending on how you define it; my impression from reading Linux lists for a while is just that we have way fewer people who understand core pieces of the system.