From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-x534.google.com (mail-ed1-x534.google.com [IPv6:2a00:1450:4864:20::534]) by sourceware.org (Postfix) with ESMTPS id A7A553858D28 for ; Wed, 3 Jan 2024 09:10:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org A7A553858D28 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org A7A553858D28 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2a00:1450:4864:20::534 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1704273049; cv=none; b=MLGMEQiWOnqGog2vWeXOMw5cPCxSpbnHRGcBSLIEaxhkFPxlbYs2IiNJoaD4l5s+N7DP66iCcbLXurUdtyfT7L8XsfmKlqtgYp7g6aarxaAeSAY8nGiocMLIJhFszLrj4AFJ4PAnRrV5MqArxZT28PPG98ydg0miFhFEBY6cFFg= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1704273049; c=relaxed/simple; bh=srscc360aVLAOLbagajG2YobyhE+ojmBwmGHr/yzMPc=; h=DKIM-Signature:MIME-Version:From:Date:Message-ID:Subject:To; b=GRhJboppD4+djxpWzOuzd/IX7HaJVYysc9n5x1kQT7kYoZzJRLwTDekpaesENojxtJn/0wdqvzDsweZaS3kwMb07QDssaYf5LlVQ3kqt68x7vN+DUmBLE8arMwHCKsf2f4yQgBelbcpbRDDS+GNilY+mohksam6eB617yirmJ/g= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-ed1-x534.google.com with SMTP id 4fb4d7f45d1cf-556ab8b85e3so442229a12.1 for ; Wed, 03 Jan 2024 01:10:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1704273045; x=1704877845; darn=cygwin.com; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :from:to:cc:subject:date:message-id:reply-to; bh=0ILdexwG8ZZT90hDq+15eai92MJhQTIM5ARp1TltU14=; b=BdUY0HD/dK/mv9RJ1YuCpj/F0NF+p/J0IExsTtRbKlgHmkpBtGGO9ENpwjQ9VLWGRK qPzuJ2O0jlCgwtGORXGtw5ABsytyENewQW2YgjyzLyIA+iS1wuz7UkOnW9GcdYUXrXt+ 2xsaaLWzPjZOPVih/srzo4k6L6+OR7UE4Yfjl0Rvw49EC7QxfgA+hX02k/u08awYE5bv 03axPutEC7iOcT7UbsSz3Cdt/xDmsY4+Gzy9rNoA4SdHLir4VG4ptXt6rsMZFoa1lIuB R7kP6BMv5qiQadlaQYsg3/aoRX6P7FxrcrJ/OOzz+EyTTgzFp6yTw5CNy0vemlRMbxks aJzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704273045; x=1704877845; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0ILdexwG8ZZT90hDq+15eai92MJhQTIM5ARp1TltU14=; b=n0Ja6t/5OodR+VPwW02xCw3Yd6mY4UTgc/Fvxt/pdZUIVbY4bfboHWLAwBMDiTEHU9 /4fD2IwBQlXn090TkEVi2dgOEDYRVyysKIWUGQjZ42TqR8QI0NkzIQMJbvvrP82UGAQM FoAOJqscd74oUA2ZsfFjOjTzw//Fegt4ddsP86O4blkj/aMGevxgcKesFlny3bmS4kEn 1nlgMmHVDdZL/dimfx18GTQ4ej98zJSBsqtkzlshem3EkiUqjIGKEouZr3yjf2afZ6B3 BVp4ary52koQ1ibt8YmwC+Mj30P24uARmbmodEV16GNc/HMcvE3nSustHjSlOT24xU0N d8Qw== X-Gm-Message-State: AOJu0YzL3w1S+GqDH36mzTB7Fp7/9XL/Lh3j5D7b9fzTRllYSvPrk2Ut n0Rl26blTpR3ojRUSWZUUjXKDgHhl/8qXZ/7QeAxEiglctw= X-Google-Smtp-Source: AGHT+IEDci7FeZ0mF3D6h+avyktDRaBNCQF+v93FbQrznr4VGBzwGHJ+3z6r1XhJ75PSaRjMeAhxLruHNVGfm7+QYow= X-Received: by 2002:a05:6402:120d:b0:554:448d:c4a5 with SMTP id c13-20020a056402120d00b00554448dc4a5mr676660edw.13.1704273045329; Wed, 03 Jan 2024 01:10:45 -0800 (PST) MIME-Version: 1.0 References: <11fb8fb3-c7ea-4be8-90ad-8addc5a7b912@gmail.com> <92531229-4810-4c9c-89d2-67ee710a7863@SystematicSW.ab.ca> In-Reply-To: <92531229-4810-4c9c-89d2-67ee710a7863@SystematicSW.ab.ca> From: Cedric Blancher Date: Wed, 3 Jan 2024 10:10:09 +0100 Message-ID: Subject: Re: Qemu packages for Cygwin? To: cygwin@cygwin.com Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-0.4 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Mon, 18 Dec 2023 at 18:33, Brian Inglis via Cygwin wrote: > > On 2023-12-18 00:14, Dan Shelton via Cygwin wrote: > > On Mon, 18 Dec 2023 at 07:54, Marco Atzeri via Cygwin wrote: > >> On 18/12/2023 07:42, Dan Shelton via Cygwin wrote: > >>> Does Cygwin come with qemu packages? > > >> why should an "Unix Emulation layer" that run in "User Space" > >> trying to run a "Full-system emulation" (https://www.qemu.org/) ? > >> It seems like using square wheels > > > Nope. The Qemu packages on LInux have a much more wider functionality, > > and more features, compared to the TUSBTADI "The User Should Be > > Treated As Dumb Idiot" versions on Windows. It absolutely makes sense. > > Cygwin has trouble providing some POSIX features under Windows due to its API > limitations, using "documented" Windows APIs, allowing it to run under ReactOS, > Wine, and similar emulators, with which there is some interchange. > > It does not provide or support much in the way of privileged Unix or Windows > features or access, except for providing emulation for running daemons as > services, and some caching of SAM, AD, and process info. > > It is totally inadequate as a platform to provide or support any x86 > virtualization or even virtual machine management features, as it can not > provide access to any machine features that do not have "documented" Windows APIs. > Look at the /proc filesystem emulation limitations for examples of where Windows > lacks APIs to get information available under Linux. > > You complain elsewhere about performance: I am also complaining about performance, but it is NOT "performance in general": What really sucks is the filesystem inode operations and file name lookup, e.g. /bin/find&friends are absurdly slow because of the link emulation and the inflation of syscalls caused by it - just up to five times more accesses just to handle filename, filename.lnk, filename.lnk.exe, filename.lnk.bat etc Other areas have adequate performance, e.g. read/write performance is OK > can you imagine how bad it would be, > compared to Hyper-V, WSL, VirtualBox, etc. No, qemu is called the "quick emulator", and has more functionality than just being a hypervisor, like being able to emulate ARM and SPARC platforms. Even if the x86 hypervisor cannot be used, there is still lots of functionality. If there are bugs in the POSIX emulation layer, then those bugs should be 1) documented and 2) fixed. Also please do not shoot down package proposals out of the FEAR that "something" might not work. Ced -- Cedric Blancher [https://plus.google.com/u/0/+CedricBlancher/] Institute Pasteur