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From: Avi Kivity <avi@redhat.com>
To: Xupeng Yun <recordus@gmail.com>
Cc: kvm@vger.kernel.org
Subject: Re: High latency with VirtIO NIC
Date: Thu, 24 Mar 2011 16:27:25 +0200	[thread overview]
Message-ID: <4D8B54CD.1070602@redhat.com> (raw)
In-Reply-To: <AANLkTinnzgcnOzuG9+Wdc62q=wBA=4htAtHwaYBHpZ1_@mail.gmail.com>

On 03/24/2011 04:24 PM, Xupeng Yun wrote:
> On Thu, Mar 24, 2011 at 22:08, Avi Kivity<avi@redhat.com>  wrote:
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3582 ttl=64 time=3.08 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3583 ttl=64 time=1.10 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3584 ttl=64 time=1.03 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3585 ttl=64 time=3.55 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3586 ttl=64 time=1.29 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3587 ttl=64 time=0.710 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3588 ttl=64 time=64.4 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3589 ttl=64 time=0.271 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3590 ttl=64 time=0.563 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3591 ttl=64 time=1.66 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3592 ttl=64 time=0.939 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3593 ttl=64 time=0.819 ms
> >>  64 bytes from app211 (192.168.1.211): icmp_seq=3594 ttl=64 time=16.5 ms
> >>
> >>  --------------------------- ping KVM guest (app211) from the host
> >>  ---------------------------
> >>
> >>  any idea?
> >>
> >
> >  Isn't it normal?  With heavy load, packets start to queue.
>
>
> Thank you, if the performance drop (from 0.15ms to 1-64ms) at this
> workload is normal,  I am okay with it.

I don't know if this is exactly the point at which latency should rise; 
what I'm saying is that it can't remain low at all load levels.


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


  reply	other threads:[~2011-03-24 14:27 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-24  0:37 High latency with VirtIO NIC Xupeng Yun
2011-03-24 10:22 ` Avi Kivity
2011-03-24 13:45   ` Xupeng Yun
2011-03-24 13:50     ` Xupeng Yun
2011-03-24 14:08     ` Avi Kivity
2011-03-24 14:24       ` Xupeng Yun
2011-03-24 14:27         ` Avi Kivity [this message]
2011-03-24 14:34           ` Xupeng Yun

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