<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>kashyapc</author><text>Launching QEMU directly is not merely &amp;quot;tricky&amp;quot;, but incredibly inefficient and ineffective once you need something that&amp;#x27;s beyond bare minimal.&lt;p&gt;E.g. here is a minimal QEMU command-line that gives you access to a serial console in the guest:&lt;p&gt;`qemu-system-x86_64 -display none -no-user-config -nodefaults -m 2048 -device virtio-scsi-pci,id=scsi -device virtio-serial-pci -serial stdio -drive file=&amp;#x2F;export&amp;#x2F;cirros.qcow2,format=qcow2,if=virtio`&lt;p&gt;Simple, yeah?  Now here (it&amp;#x27;s too long to post in this comment) is a real world QEMU command-line (as launched by the libvirt[1]):&lt;p&gt;htttps:&amp;#x2F;&amp;#x2F;kashyapc.fedorapeople.org&amp;#x2F;Fedora-28-QEMU-command-line-by-libvirt.txt&lt;p&gt;Compare and contrast the number of devices that libvirt adds.&lt;p&gt;FWIW, I strongly recommend to use libvirt to launch your QEMU-based guests.  It is far more effective, and more importantly, provides security infrastructure like running the QEMU process as an unprivileged user, protecting the QEMU process (and its associated disk iamges) via the SELinux-based sVirt mechanism, and so forth.&lt;p&gt;Check out these[2] slides (recording is online, too) on &amp;quot;Security in QEMU&amp;quot; from one of the QEMU maintainers, Stefan Hajnoczi, at last year&amp;#x27;s KVM Forum in Edinburgh.&lt;p&gt;[1] &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;libvirt.org&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;libvirt.org&amp;#x2F;&lt;/a&gt;&lt;p&gt;[2] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;vmsplice.net&amp;#x2F;~stefan&amp;#x2F;stefanha-kvm-forum-2018.pdf&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;vmsplice.net&amp;#x2F;~stefan&amp;#x2F;stefanha-kvm-forum-2018.pdf&lt;/a&gt;</text><parent_chain><item><author>idoubtit</author><text>Last week, I intended to replace VirtualBox with QEMU for my personal use. The spartiate documentation made it really hard. I lack the competence to seriously contribute.&lt;p&gt;The official documentation just explains the numerous parameters. It also points to tutorials (wikibook, etc), which unfortunately are very basic and out of sync. Even Arch Linux does not provide a good documentation (lack of clarity, some obsolete syntax, &amp;quot;Networking&amp;quot; section is a mess...). Like often, Debian&amp;#x27;s wiki is obsolete, and even their QEMU images are 5 years old. I had to combine the following 3 sources and a lot of try and guesses to build my VMs.&lt;p&gt;QEMU Gentoo : &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;wiki.gentoo.org&amp;#x2F;wiki&amp;#x2F;QEMU&amp;#x2F;Options&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;wiki.gentoo.org&amp;#x2F;wiki&amp;#x2F;QEMU&amp;#x2F;Options&lt;/a&gt;&lt;p&gt;QEMU official : &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;qemu.weilnetz.de&amp;#x2F;doc&amp;#x2F;qemu-doc.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;qemu.weilnetz.de&amp;#x2F;doc&amp;#x2F;qemu-doc.html&lt;/a&gt;&lt;p&gt;KVM Performance : &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.linux-kvm.org&amp;#x2F;page&amp;#x2F;Tuning_KVM&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.linux-kvm.org&amp;#x2F;page&amp;#x2F;Tuning_KVM&lt;/a&gt;</text></item></parent_chain></comment><story><title>QEMU v4.0.0 released</title><url>https://www.qemu.org/2019/04/24/qemu-4-0-0/</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>pm215</author><text>My recommendation for that sort of use would be to look at using a &amp;#x27;management layer&amp;#x27; app that sits above QEMU and handles all the fiddly command line details for you -- &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;virt-manager.org&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;virt-manager.org&amp;#x2F;&lt;/a&gt; (which uses&amp;#x2F;is part of libvirt) is a popular one, I think. The QEMU project has kind of settled on the philosophy of being the low-level tool which provides you &amp;quot;full manual control&amp;quot; and interfaces for a higher-level UI to make use of. User-friendliness is not really our forte and so we let other projects provide that part.</text><parent_chain><item><author>idoubtit</author><text>Last week, I intended to replace VirtualBox with QEMU for my personal use. The spartiate documentation made it really hard. I lack the competence to seriously contribute.&lt;p&gt;The official documentation just explains the numerous parameters. It also points to tutorials (wikibook, etc), which unfortunately are very basic and out of sync. Even Arch Linux does not provide a good documentation (lack of clarity, some obsolete syntax, &amp;quot;Networking&amp;quot; section is a mess...). Like often, Debian&amp;#x27;s wiki is obsolete, and even their QEMU images are 5 years old. I had to combine the following 3 sources and a lot of try and guesses to build my VMs.&lt;p&gt;QEMU Gentoo : &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;wiki.gentoo.org&amp;#x2F;wiki&amp;#x2F;QEMU&amp;#x2F;Options&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;wiki.gentoo.org&amp;#x2F;wiki&amp;#x2F;QEMU&amp;#x2F;Options&lt;/a&gt;&lt;p&gt;QEMU official : &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;qemu.weilnetz.de&amp;#x2F;doc&amp;#x2F;qemu-doc.html&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;qemu.weilnetz.de&amp;#x2F;doc&amp;#x2F;qemu-doc.html&lt;/a&gt;&lt;p&gt;KVM Performance : &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.linux-kvm.org&amp;#x2F;page&amp;#x2F;Tuning_KVM&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.linux-kvm.org&amp;#x2F;page&amp;#x2F;Tuning_KVM&lt;/a&gt;</text></item></parent_chain></comment><story><title>QEMU v4.0.0 released</title><url>https://www.qemu.org/2019/04/24/qemu-4-0-0/</url></story>