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From: Avi Kivity <avi@redhat.com>
To: Jan Kiszka <jan.kiszka@web.de>
Cc: "Michael Tokarev" <mjt@tls.msk.ru>,
	"René Pfeiffer" <lynx@luchs.at>,
	kvm@vger.kernel.org
Subject: Re: I/O performance of VirtIO
Date: Thu, 22 Oct 2009 18:29:14 +0200	[thread overview]
Message-ID: <4AE0885A.1080304@redhat.com> (raw)
In-Reply-To: <4AD41FB8.6000209@web.de>

On 10/13/2009 08:35 AM, Jan Kiszka wrote:
> It can be particularly slow if you use in-kernel irqchips and the
> default NIC emulation (up to 10 times slower), some effect I always
> wanted to understand on a rainy day. So, when you actually want -net
> user, try -no-kvm-irqchip.
>    

This might be due to a missing SIGIO or SIGALRM; -no-kvm-irqchip 
generates a lot of extra signals and thus polling opportunities.

I see 300kB/sec from slirp; always assumed it was due to missing tcp 
features.

-- 
error compiling committee.c: too many arguments to function


  reply	other threads:[~2009-10-22 16:31 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-12 20:49 I/O performance of VirtIO René Pfeiffer
2009-10-12 21:45 ` Michael Tokarev
2009-10-12 21:54   ` René Pfeiffer
2009-10-13  6:35   ` Jan Kiszka
2009-10-22 16:29     ` Avi Kivity [this message]
2009-10-22 22:06       ` Alexander Graf
2009-10-25  5:44         ` Avi Kivity
2009-10-26  8:12           ` Jan Kiszka
2009-10-26  8:35             ` Avi Kivity

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