qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [patch] non-blocking disk IO


From: Brad Campbell
Subject: Re: [Qemu-devel] [patch] non-blocking disk IO
Date: Wed, 05 Oct 2005 00:40:23 +0400
User-agent: Mozilla Thunderbird 1.0+ (X11/20050712)

John Coiner wrote:

Non-blocking disk IO now works for any type of disk image, not just "raw" format. There is no longer any format-specific code in the patch:

http://people.brandeis.edu/~jcoiner/qemu_idedma/qemu_dma_patch.html

You might want this patch if:
 * you run a multitasking guest OS,
 * you access a disk sometimes, and
 * you wouldn't mind if QEMU ran a little faster.

Why I have not got feedback in droves I do not understand ;)

I have 3 or 4 images here (of different flavours of windows from 95 -> XP) that I have base images about 4G and then I use qcow files to do my testing and other damaging stuff to. With this patch qemu will not boot the qcow files but will boot the base images (I copy them and then try to boot to test). As soon as I patch -R && make, qemu will boot the qcow files no problems..

Let me clarify that..
qemu-img create -f qcow xp.img 4G
qemu -cdrom xp.iso -hda xp.img -boot d (Install XP from scratch)
qemu-img create -b xp.img -f qcow xp2.img
qemu -hda xp2.img

This gives me an invalid hard disk error. If I revert the patch I can boot from xp2.img with no issues. With or without the patch I can boot from xp.img.

I have tried installing XP with and without the patch and that works fine..

Regards,
Brad
--
"Human beings, who are almost unique in having the ability
to learn from the experience of others, are also remarkable
for their apparent disinclination to do so." -- Douglas Adams




reply via email to

[Prev in Thread] Current Thread [Next in Thread]