From: Avi Kivity <avi@redhat.com>
To: "Hao, Xudong" <xudong.hao@intel.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: KVM Test report, kernel 647e9e... qemu 7811d4...
Date: Sun, 28 Mar 2010 12:09:56 +0300 [thread overview]
Message-ID: <4BAF1CE4.8030401@redhat.com> (raw)
In-Reply-To: <EB8593BCECAB3D40A8248BE0B6400A38466289D6@shzsmsx502.ccr.corp.intel.com>
On 03/28/2010 12:03 PM, Hao, Xudong wrote:
> Avi Kivity wrote:
>
>> You need to fold the -hda parameter into -driver, so the whole command
>> line becomes
>>
>> qemu-system-x86_64 -m 512 -smp 4 -net
>> nic,macaddr=00:16:3e:79:0c:db,model=rtl8139 -net
>> tap,script=/etc/kvm/qemu-ifup -drive
>> file=/share/ltp_guest.img,cache=writeback
>>
>>
>> -hda is deprecated, it forces cache=writethrough.
>>
> Okay, cache=writeback can improve 28% performance of diotest, it cost 135 seconds which cost 182 sconds with cache=writethrough.
> But in the report of bug, there was 2.53 times downgrade performance than before, so maybe still need somewhere tuning.
>
>
Can you try creating the image with
qemu-img create -f qcow2 -o cluster_size=4096 guest.img <size>
That reduces the cluster size to 4096, maybe that helps diotest.
--
error compiling committee.c: too many arguments to function
prev parent reply other threads:[~2010-03-28 9:09 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-08 6:40 KVM Test report, kernel 647e9e... qemu 7811d4 Hao, Xudong
2010-03-24 15:17 ` Avi Kivity
2010-03-26 8:39 ` Hao, Xudong
2010-03-26 9:54 ` Avi Kivity
2010-03-28 9:03 ` Hao, Xudong
2010-03-28 9:09 ` Avi Kivity [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4BAF1CE4.8030401@redhat.com \
--to=avi@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=xudong.hao@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox