The code reported below with KVM needs 60 minutes to complete aganist 4 minutes without. I just wondering if with KVM enabled is possible to match the performance of simple Qemu. #include "lib/lib.h"
What is your expecting performance? Vga of stdvga and cirrus are all software renderer, and their IO addresses were all emulated by virtual memory (i.e. mmap). The doubled R/W access time seems be re
I tried to launch Qemu with Vga set to cirrus,std and vmware. Same bad numbers. Is my only option to patch Qemu + KVM? I also noted some slowdown in my ata custom driver. The driver currently support
I tried to launch Qemu with Vga set to cirrus,std and vmware. Same bad numbers. Is my only option to patch Qemu + KVM? I also noted some slowdown in my ata custom driver. The driver currently support
I tried to launch Qemu with Vga set to cirrus,std and vmware. Same bad numbers. Is my only option to patch Qemu + KVM? I also noted some slowdown in my ata custom driver. The driver currently support
On 04/05/2016 10:50, giuseppe maugeri wrote: Hi, i'm developing a custom kernel for x86 platform.So Far i used as virtual environment Simics. Recently i decided to move to Qemu. Running my kernel on
Hi, i'm developing a custom kernel for x86 platform.So Far i used as virtual environment Simics. Recently i decided to move to Qemu. Running my kernel on Qemu I found it tremendously slow even with K
Found it... ARP routing problem that just made the machines feel slow. Each guest was using an identical internal mac address on its tap device. I override each in the network started file and all is
On 3/25/24 09:19, Pierrick Bouvier wrote: On 3/24/24 22:45, Luca Vajen wrote: Hello, I'm not sure if this is the right place to ask for help. I guess in the worst case you might get a laugh out of th
On 3/24/24 22:45, Luca Vajen wrote: Hello, I'm not sure if this is the right place to ask for help. I guess in the worst case you might get a laugh out of this. There's an old game I would like to pl
Hello, I'm not sure if this is the right place to ask for help. I guess in the worst case you might get a laugh out of this. There's an old game I would like to play again and someone made a ready-to
Hi Serdar, I'm a newbie in QEMU and I'm using it on an Apple Silicon macOS (ARM-based). I use the default accelerator tcg to run a virtual machine with Ubuntu but it is quite slow. I tried commands l
Am 26.02.24 um 11:33 schrieb Serdar Bahar: Hello, I'm a newbie in QEMU and I'm using it on an Apple Silicon macOS (ARM-based). I use the default accelerator tcg to run a virtual machine with Ubuntu b
Hi, I am new to QEMU/KVM and would like to have some info before trying to switch from VirtualBox, for a particular use case. Currently, I have a VirtualBox image running Windows 10 with a custom VP
Hello All, This is my first post on qemu, recently starting troubleshooting one of vm migration slowness, having below question unanswered for myself 1) will qemu uses host main memory for migratio
... Oh I see. You're saying that -drive ...,discard=ignore Does not prevent Windows (guest OS) from trying the discard=trim=unmap on the virtio disk device, merely those operations get ignored by QEM
Frantisek Rysanek <Frantisek.Rysanek@post.cz> Hi D, I'm not sure what exactly your goal is. Prevent the guest OS from realizing, that the HDD is of type "virtio"? In that case I'd look at how the har
This will only display at translation time, so when the code is first encountered. That would be weird. However CPU will "miss" code that doesn't return to the main loop due to TB patching. -d nochai
Hi all! I need to simulate some code for a bare metal ARM application, and get a trace of every machine instruction that gets executed. Attaching GDB to the qemu-system-arm works, but of course it is
We don't do that. The pipeline is run on each pull request which can be anything from a few patches to a few hundred. And the reason is obvious because we are guarding against introducing regression
Hi Sir/Madam, Myself is Mallikarjuna, i am new to Qemu environment, i installed Qemu in my Ubuntu system. Once after the installation i am facing very slow, is ther any additional configuration to be
I have QEMU built via MacPorts working. But, I don't have window resizing and cut-and-paste. I think the way to get that working is via Spice. I had spice running on Windows x86, but I am having
Hi all, I've been investigating slow guest boot times for VMs running on (amd64) macOS hosts, using accel=hvf. What I've found is that boot time scales poorly with guest CPU count. Approximate boot t
hi all, I'm trying to use vhost user gpu, but the guest(ubuntu 22.04) is very slow, and nearly no response, First, i run './vhost-user-gpu -s vgpu.sock -v virgl' then, i start qemu with 'x86_64-softm
hi, I play to emulate the Raspberry Pi and, to avoid having to wait for the (re)start of my slow VM, I recorded a snapshot at the end of the first boot. but when I reload this snapshot, I have a lot
A couple more points: How many CPU's (sockets) does your motherboard have? Multi-socket machines are more or less in the NUMA territory. Suboptimal process scheduling / memory allocation "decisions"
Hello, all I’m install ubuntu 20.04 on an arm64 virtual machine using qemu-5.1.0. (host is also ubuntu 20.04, am64 machine) The final command is below. (the LD_LIBRARY_PATH setting was needed f
The lack of further in_asm logging does not mean that guest instructions are not running. in_asm logging happens at *translate* time, which is to say the first time QEMU encounters any particular ins
Hi Philippe, Thank for your email I investigated your advice, first checked the CPU's programmer's reference manual and it has wait for interrupt instruction. then to check what instructions are e
Your question is reaching the list, but this mail ought to be informative: https://lists.gnu.org/archive/html/qemu-devel/2021-09/msg02463.html In short, the fact that you are seeing performance pena
Your question is reaching the list, but this mail ought to be informative: https://lists.gnu.org/archive/html/qemu-devel/2021-09/msg02463.html In short, the fact that you are seeing performance penal
Yes, as i know this ist the qemu list, but as i see from the response (i am on this list since 5 month), its more or less developement and only if you get "luck" a answer for "simple" user questions
hello everybody, virtual FAT disk image - which is a convenient way to transfer files to the guest without having to activate its network - seems to work very poorly with Windows : do you have the sa
Hi, I have an issue with QEMU. When I run VMs, I lock my cursor, but when I move it to the very edge of the QEMU window, my cursor shows again. This is very annoying because when I boot OSs, there ar
I guess you mean how to improve "qcow2" performance. If you use "qcow" format the best way is to switch to "qcow2". 'directsync' is using direct I/O, but calls fsync() for every write. This is the sl
Hi, I am using QEMU 5.05 and I keep getting some issues when running QEMU under multi-core configuration. I used a qcow2 ubuntu 18.04 image and launched the VM in QEMU TCG mode, having the multicore
2021-04-09 18:05, Jagannadha Bhamidipati rašė: I have raspberry pi 400 Installed OS - Ubuntu (Release 20.10 (Groovy Gorilla) 64-bit) Mate (MATE 1.24.1) Kernel Linux - Kernel Linux 5.8.0-1019-raspi
Thanks for your response. Different runs lead to different results. So not easy to reproduce. Thank you for mentioning rr-project. Maybe, I can have a try. GDB has its own record & replay function.
I appreciate your kindness. After all, I could hear the nostalgic startup sound by sb16 emulation. I'm relieved to hear the error is harmless. There still remains another problem. Sometimes I can hea
Dear all! I appreciate your kindness. After all, I could hear the nostalgic startup sound by sb16 emulation. I'm relieved to hear the error is harmless. There still remains another problem. Sometimes
Peter, Thank you for your prompt response. It does look like the failure in the scsi driver is what is causing the root device not to be created. I can see that there has been an issue raised on this
This is your problem, I think -- the new kernel fails to correctly init the SCSI adaptor, and so it never sees the disk, and then later the kernel panics becasue you told it to use a disk that's not
You can't. QEMU will only ever check for and take interrupts at the end of a TB. The best you can do is that you can use the '-singlestep' command line option to force QEMU to put exactly 1 instruct
You can't. QEMU will only ever check for and take interrupts at the end of a TB. The best you can do is that you can use the '-singlestep' command line option to force QEMU to put exactly 1 instructi
Yeah this is the mechanism I was about to suggest. If you can guarantee your library function is called before any of the code you want to instrument then this can be used as a "trigger". -- Alex Ben
Our approach to this problem was to make the plugin sensitive to the execution of well-chosen instructions to turn on/turn off the actions of the plugin. The plugin will still be called (don't unregi
Hi! I installed qemu on a Windows 10 pc (using Powershell and Scoop). I do not have administrator password and I can't change boot order (first usb, second internal hd, etc). I tried to install a lin
It will depend if QEMU models the device you are after. For m3 there are mps2, stellaris and netduino2 models. Yes - both normal serial ports and semihosting output can be re-directed to a file using
The analysis library runs on the Cortex-M3? There is a fairly big performance penalty for softmmu emulation but given the speed of most modern PCs compared to microcontrollers you would possibly be
The following message is a courtesy copy of an article that has been posted to gmane.comp.emulators.qemu.user as well. The analysis library runs on the Cortex-M3? There is a fairly big performance pe
I have a pretty basic question about how qemu works... I have an analysis library (no source) for ARM Cortex M3 processor that I'd like to run on many files. My hardware would be very slow doing this
I have a pretty basic question about how qemu works... I have an analysis library (no source) for ARM Cortex M3 processor that I'd like to run on many files. My hardware would be very slow doing this
It's not supposed to disable TB caching, and in my experience it does not (no TB caching at all is incredibly slow). If it's doing that on PPC that would be worth investigating. I do almost all of my
<snip> You can - the emulation is all in-order. The only real effect of accessing some sort of HW device is the real wall-clock time of the instruction will be longer (as QEMU has more to do). For mu
Le 31/03/2020 à 16:38, Alex Bennée a écrit : Le 31/03/2020 à 02:28, Benjamin a écrit : Perhaps you're looking for something like this? https://wiki.qemu.org/Internships/ProjectIdeas/CacheModell
Except in the special case where you tell QEMU to map a guest serial port directly through to a physical host serial port, it doesn't matter, because QEMU doesn't emulate serial ports at a level of d
On 31/10/2019 09:12, bilsch01 wrote: I have executable code for my simple OS in a binary file (jsec2.bin) created using nasm assembler. I have been running it from a flash drive with a boot sector th
I have executable code for my simple OS in a binary file (jsec2.bin) created using nasm assembler. I have been running it from a flash drive with a boot sector that loads the executable to memory and
I think I understand the nuances of your last note on performance comparison, indeed my approach there was not correct. The only real ARM hardware I have is an rpi3b+ which isnt powerful enough for t
Emulation isn't fast, generally speaking. It is possible to just drop an x86 binary of a cross-compiler (x86-to-arm) into your chroot as its 'gcc' binary, and then you'll get native performance of th
Thank you for your reply. I am though stumped by that large of degradation using that simple test and when I attempted to compile my actual project (chromium) in the chroot, it was insanely slow. May
Generally, rebase is going to be slower because it reads some clusters and compares the old with the new backing file to see whether they are the same. commit will not do that. (OTOH, if there are ma
I can announce that I have successfully built QEMU 4.0.0 in Solaris 10 on a Sun M3000 Sparc VII using gcc 7.3.0 and OpenCSW tools: PKG_CONFIG_PATH=/opt/csw/lib/pkgconfig:/usr/local/lib/pkgconfig:/opt
I give the wrong ifname in -netdev which not attached to the bridge on SVM host. Sorry for slow reply. Can you share the detail of the wrong parameters? In case other people have the same issue. Why
Sorry for slow reply. Can you share the detail of the wrong parameters? In case other people have the same issue. Why you dump the secondary_in and find out pri_rs.buf? pri_rs.buf should used by pri
Sure, If it is convenient, you can try to debug under your environment and send a patch to Qemu community. I am very happy to review it. Thanks Zhang Chen Your answer make sense to me. Different netw
Your answer make sense to me. Different network environment may result in that status. I think more attention should be paid on the compatibility of COLO Proxy. 发件人: Zhang, Chen <address@hidden
I have tested Proxy with QMP: "{'execute': 'trace-event-set-state', 'arguments': {'name': 'colo*', 'enable': true} }" I got this nothing except this logs on PVM side: address@hidden:colo_compare_main
I have tested Proxy with QMP: "{'execute': 'trace-event-set-state', 'arguments': {'name': 'colo*', 'enable': true} }" I got this nothing except this logs on PVM side: address@hidden:colo_compare_main
This version: https://github.com/coloft/qemu/tree/colo-v4.1-periodic-mode This is old version from 3 years ago, please drop it, use qemu upstream codes. Another question: What is the relationship bet
Which version? COLO project always said the PVM and SVM execute in parallel. Thanks Zhang Chen But in earlier version, I noticed that SVM always inmigration status even doing checkpoint. No operation
Thanks for help ! I don’t know why we keep switching SVM between Run and Stop ? Why we don’t keep SVM inmigration status ? Because we need do checkpoint to sync all status between PVM and SVM. We
Thanks for help ! I don’t know why we keep switching SVM between Run and Stop ? Why we don’t keep SVM inmigration status ? Thanks, Zhengtao 发件人: Zhang, Chen <address@hidden> 发送时间: 2
I don't rely on the entries to be cached; I configured the systems registers to perform a table walk on TLB miss, so if the entry is discarded the MMU happily loads another one. The problem seems to
If your guest code is relying on entries staying in the TLB then it is not correct -- there is no architectural guarantee that an entry is ever kept in the TLB. An implementation is free to throw out
You have various knobs to control what happens on write failures, both on the source and on the destination (on-source-error and on-target-error) as well as how synchronized the image will be (Mirror
Replied inline. Eric, I watched your kvm forum video https://www.youtube.com/watch?v=zQK5ANionpU. Which cleared out somethings for me. Lets say you have a disk of size 10GB, I had assumed that, if dr
OK, I've pinged awesome Ubuntu people and they gave me the answer: I had to use the cdrom through SCSI rather than the default virtio, because the installer doesn't have the virtio drivers currently:
Somewhat a baffling situation here. I have Debian buster x86_64 running just fine and also the default qemu packages from the Debian folks. However those are 2.12.0 whereas my own local builds from t
Hi Amit, Thanks for your response. See inline comments. Amit Shah <address@hidden> 于2018年10月16日呺 上午2:51写道： Yes. We just register the virtio-serial, and not use it, it brings the
If you use multiple virtio-net (or blk) devices -- just register, not necessarily use -- does that also bring the performance down? I suspect it's the number of interrupts that get allocated for the
Add Amit Shah. After some tests, we found: - the virtio serial port number is inversely proportional to the iSCSI virtio-blk-pci performance. If we set the virio-serial ports to 2("<controller type='
Hi Dave, My comments are in-line. Dr. David Alan Gilbert <address@hidden> 于2018年10月1日呸 下午7:41写道： I'm using fio, the config is: [global] ioengine=libaio iodepth=128 runtime=120 ti
first: i've followed (years ago) this blog to install debian wheezy on sparc64, works with Debian 7.11 (newer debians removed sparc support) - beware: its awfully slow, but it works/runs then i tried
Dear Mr. Maydell,. Na piatok, 14. septembra 2018 16:35:13 CEST Peter Maydell napísali: Thank you.. I seems graphics is only problem when using HAX and quemeu for us. We would like to be informed abo
That's weird. The HAX support should be entirely orthogonal to whether the display is being viewed fullscreen or not. (I guess it's possible that we're not getting the "hax needs to tell us about dir
Dear Qemu experts, We need to run DOS based CAD/CAM program via disk image as system in Windows7 or more recent I works but it is too slow for large CAM -NC programs therefore we tried to use HAX via
Update: I've also checked I/O and memory usage on my host when running emulation. I/O is zero, memory swapping turned off, a lot of free memory. So I didn't observe any host bottlenecks which would c
Also, recent kernel versions do not need to "eat" the SIG_IPI anymore. More precisely, on older versions, SIG_IPI was temporarily unblocked during the KVM_RUN ioctl but never delivered to the CPU thr
I have bridge on my Linux PC: bridge name bridge id STP enabled interfaces br1 8000.001b210e62eb no enp4s1 wlan0 But I run hostapd on wlan0, I don't know if it works as a client, but I suspect it doe
Here's what I want to do: use Qemu on my Windows host while on Wi-Fi. Currently, I can only use SLIRP with Wi-Fi, but since it's quite slow I would like to know what other options do I have. When the