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* KVM performance
@ 2009-04-03 11:32 BRAUN, Stefanie
  2009-04-06 11:45 ` Avi Kivity
  2009-04-06 12:13 ` Hauke Hoffmann
  0 siblings, 2 replies; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-03 11:32 UTC (permalink / raw)
  To: kvm


Hallo,

as I want to switch from XEN to KVM I've made some performance tests
to see if KVM is as peformant as XEN. But tests with a VMU that receives
a streamed video, adds a small logo to the video and streams it to a
client
have shown that XEN performs much betten than KVM. 
In XEN the vlc (videolan client used to receive, process and send the
video) process 
within the vmu has a cpuload of 33,8 % whereas in KVM
the vlc process has a cpuload of 99.9 %.
I'am not sure why, does anybody now some settings to improve
the KVM performance?

Thank you.
Regards, Stefanie.


Used hardware and settings:
In the tests I've used the same host hardware for XEN and KVM:
- Dual Core AMD 2.2 GHz, 8 GB RAM
- Tested OSes for KVM Host: Fedora 10, 2.6.27.5-117.fc10.x86_64 with kvm
version 10.fc10 version 74
                            also tested in january: compiled kernel with
kvm-83

- KVM Guest settings: OS: Fedora 9 2.6.25-14.fc9.x86_64 (i386 also
tested)
                      RAM: 256 MB (same for XEN vmu)
                      CPU: 1 Core with 2,2 GHz (same for XEN vmu)
			    tested nic models: rtl8139, e1000, virtio

Tested Scenario: VMU receives a streamed video , adds a logo (watermark)
to the video stream and then streams it to a client

Results:
	
XEN:
Host cpu load (virt-manager): 		23%
VMU  cpu load (virt-manager):			18 %	
VLC process within VMU (top):			33,8%			

KVM:
no virt-manager cpu load as I started the vmu with the kvm command
Host cpu load :					52%
qemu-kvm process (top)				77-100%
VLC process within vmu (top):			80 - 99,9%

KVM command to start vmu
/usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 256 -net
nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10,model=virtio -net
tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qem
u-ifdown -vnc 127.0.0.1:1 -k de --daemonize





________________________________

Alcatel-Lucent Deutschland AG
Bell Labs Germany
Service Infrastructure, ZFZ-SI
Stefanie Braun
Phone:   +49.711.821-34865
Fax:     +49.711.821-32453

Postal address:
Alcatel-Lucent Deutschland AG
Lorenzstrasse 10
D-70435 STUTTGART

Mail: stefanie.braun@alcatel-lucent.de

 

Alcatel-Lucent Deutschland AG
Sitz der Gesellschaft: Stuttgart - Amtsgericht Stuttgart HRB 4026
Vorsitzender des Aufsichtsrats: Michael Oppenhoff Vorstand: Alf Henryk
Wulf (Vors.), Dr. Rainer Fechner

________________________________

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: KVM performance
  2009-04-03 11:32 KVM performance BRAUN, Stefanie
@ 2009-04-06 11:45 ` Avi Kivity
       [not found]   ` <133D9897FB9C5E4E9DF2779DC91E947C51834A@SLFSNX.rcs.alcatel-research.de>
  2009-04-06 12:13 ` Hauke Hoffmann
  1 sibling, 1 reply; 14+ messages in thread
From: Avi Kivity @ 2009-04-06 11:45 UTC (permalink / raw)
  To: BRAUN, Stefanie; +Cc: kvm

BRAUN, Stefanie wrote:
> Hallo,
>
> as I want to switch from XEN to KVM I've made some performance tests
> to see if KVM is as peformant as XEN. But tests with a VMU that receives
> a streamed video, adds a small logo to the video and streams it to a
> client
> have shown that XEN performs much betten than KVM. 
> In XEN the vlc (videolan client used to receive, process and send the
> video) process 
> within the vmu has a cpuload of 33,8 % whereas in KVM
> the vlc process has a cpuload of 99.9 %.
> I'am not sure why, does anybody now some settings to improve
> the KVM performance?
>   

Is this a tcp test?

Can you test receive and transmit separately?

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


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: KVM performance
  2009-04-03 11:32 KVM performance BRAUN, Stefanie
  2009-04-06 11:45 ` Avi Kivity
@ 2009-04-06 12:13 ` Hauke Hoffmann
  2009-04-06 16:30   ` AW: " BRAUN, Stefanie
  2009-04-07 12:58   ` BRAUN, Stefanie
  1 sibling, 2 replies; 14+ messages in thread
From: Hauke Hoffmann @ 2009-04-06 12:13 UTC (permalink / raw)
  To: kvm; +Cc: BRAUN, Stefanie

On Friday 03 April 2009 13:32:50 you wrote:
> Hallo,
>
> as I want to switch from XEN to KVM I've made some performance tests
> to see if KVM is as peformant as XEN. But tests with a VMU that receives
> a streamed video, adds a small logo to the video and streams it to a
> client
> have shown that XEN performs much betten than KVM.
> In XEN the vlc (videolan client used to receive, process and send the
> video) process
> within the vmu has a cpuload of 33,8 % whereas in KVM
> the vlc process has a cpuload of 99.9 %.
> I'am not sure why, does anybody now some settings to improve
> the KVM performance?
>
> Thank you.
> Regards, Stefanie.
>
>
> Used hardware and settings:
> In the tests I've used the same host hardware for XEN and KVM:
> - Dual Core AMD 2.2 GHz, 8 GB RAM
> - Tested OSes for KVM Host: Fedora 10, 2.6.27.5-117.fc10.x86_64 with kvm
> version 10.fc10 version 74
>                             also tested in january: compiled kernel with
> kvm-83
>
> - KVM Guest settings: OS: Fedora 9 2.6.25-14.fc9.x86_64 (i386 also
> tested)
>                       RAM: 256 MB (same for XEN vmu)
>                       CPU: 1 Core with 2,2 GHz (same for XEN vmu)
> 			    tested nic models: rtl8139, e1000, virtio
>
> Tested Scenario: VMU receives a streamed video , adds a logo (watermark)
> to the video stream and then streams it to a client
>
> Results:
>
> XEN:
> Host cpu load (virt-manager): 		23%
> VMU  cpu load (virt-manager):			18 %
> VLC process within VMU (top):			33,8%
>
> KVM:
> no virt-manager cpu load as I started the vmu with the kvm command
> Host cpu load :					52%
> qemu-kvm process (top)				77-100%
> VLC process within vmu (top):			80 - 99,9%
>
> KVM command to start vmu
> /usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 256 -net
> nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10,model=virtio -net
> tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qem
> u-ifdown -vnc 127.0.0.1:1 -k de --daemonize

Hi Stefanie,

does vlc perform operations on disc (eg caching, logging, ...)? 

When it cache you can use virtio also for the disk. 
Just change
	-hda /images/vmu01.raw
to
	-drive file=/images/vmu01.raw,if=virtio,boot=on

Regards
Hauke


>
>
>
>
>
> ________________________________
>
> Alcatel-Lucent Deutschland AG
> Bell Labs Germany
> Service Infrastructure, ZFZ-SI
> Stefanie Braun
> Phone:   +49.711.821-34865
> Fax:     +49.711.821-32453
>
> Postal address:
> Alcatel-Lucent Deutschland AG
> Lorenzstrasse 10
> D-70435 STUTTGART
>
> Mail: stefanie.braun@alcatel-lucent.de
>
>
>
> Alcatel-Lucent Deutschland AG
> Sitz der Gesellschaft: Stuttgart - Amtsgericht Stuttgart HRB 4026
> Vorsitzender des Aufsichtsrats: Michael Oppenhoff Vorstand: Alf Henryk
> Wulf (Vors.), Dr. Rainer Fechner
>
> ________________________________
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 

hauke hoffmann service and electronic systems

Moristeig 60, D-23556 Lübeck

Telefon: +49 (0) 451 8896462
Fax: +49 (0) 451 8896461
Mobil: +49 (0) 170 7580491
E-Mail: office@hauke-hoffmann.net
PGP public key: www.hauke-hoffmann.net/static/pgp/kontakt.asc

^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: KVM performance
  2009-04-06 12:13 ` Hauke Hoffmann
@ 2009-04-06 16:30   ` BRAUN, Stefanie
  2009-04-07 12:58   ` BRAUN, Stefanie
  1 sibling, 0 replies; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-06 16:30 UTC (permalink / raw)
  To: kvm; +Cc: Hauke Hoffmann

 

-----Ursprüngliche Nachricht-----
Von: Hauke Hoffmann [mailto:kontakt@hauke-hoffmann.net] 
Gesendet: Montag, 6. April 2009 14:13
An: kvm@vger.kernel.org
Cc: BRAUN, Stefanie
Betreff: Re: KVM performance

On Friday 03 April 2009 13:32:50 you wrote:
> Hallo,
>
> as I want to switch from XEN to KVM I've made some performance tests 
> to see if KVM is as peformant as XEN. But tests with a VMU that 
> receives a streamed video, adds a small logo to the video and streams 
> it to a client have shown that XEN performs much betten than KVM.
> In XEN the vlc (videolan client used to receive, process and send the
> video) process
> within the vmu has a cpuload of 33,8 % whereas in KVM the vlc process 
> has a cpuload of 99.9 %.
> I'am not sure why, does anybody now some settings to improve the KVM 
> performance?
>
> Thank you.
> Regards, Stefanie.
>
>
> Used hardware and settings:
> In the tests I've used the same host hardware for XEN and KVM:
> - Dual Core AMD 2.2 GHz, 8 GB RAM
> - Tested OSes for KVM Host: Fedora 10, 2.6.27.5-117.fc10.x86_64 with 
> kvm version 10.fc10 version 74
>                             also tested in january: compiled kernel 
> with
> kvm-83
>
> - KVM Guest settings: OS: Fedora 9 2.6.25-14.fc9.x86_64 (i386 also
> tested)
>                       RAM: 256 MB (same for XEN vmu)
>                       CPU: 1 Core with 2,2 GHz (same for XEN vmu)
> 			    tested nic models: rtl8139, e1000, virtio
>
> Tested Scenario: VMU receives a streamed video , adds a logo 
> (watermark) to the video stream and then streams it to a client
>
> Results:
>
> XEN:
> Host cpu load (virt-manager): 		23%
> VMU  cpu load (virt-manager):			18 %
> VLC process within VMU (top):			33,8%
>
> KVM:
> no virt-manager cpu load as I started the vmu with the kvm command
> Host cpu load :					52%
> qemu-kvm process (top)				77-100%
> VLC process within vmu (top):			80 - 99,9%
>
> KVM command to start vmu
> /usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 256 -net 
> nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10,model=virtio -net 
> tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/q
> em u-ifdown -vnc 127.0.0.1:1 -k de --daemonize

Hi Stefanie,

does vlc perform operations on disc (eg caching, logging, ...)? 

When it cache you can use virtio also for the disk. 
Just change
	-hda /images/vmu01.raw
to
	-drive file=/images/vmu01.raw,if=virtio,boot=on

Regards
Hauke


Hi Hauke,

Thanks for your replay.

The vlc does not perform excessive operations on disc.

Even so I've added disk virtio to the vmu setup. 
But the qemu-kvm process in the host and the
vlc process within the vmu still consume up to 100%.

Regards,
Stefanie

>
>
>
>
>
> ________________________________
>
> Alcatel-Lucent Deutschland AG
> Bell Labs Germany
> Service Infrastructure, ZFZ-SI
> Stefanie Braun
> Phone:   +49.711.821-34865
> Fax:     +49.711.821-32453
>
> Postal address:
> Alcatel-Lucent Deutschland AG
> Lorenzstrasse 10
> D-70435 STUTTGART
>
> Mail: stefanie.braun@alcatel-lucent.de
>
>
>
> Alcatel-Lucent Deutschland AG
> Sitz der Gesellschaft: Stuttgart - Amtsgericht Stuttgart HRB 4026 
> Vorsitzender des Aufsichtsrats: Michael Oppenhoff Vorstand: Alf Henryk 
> Wulf (Vors.), Dr. Rainer Fechner
>
> ________________________________
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in the 
> body of a message to majordomo@vger.kernel.org More majordomo info at  
> http://vger.kernel.org/majordomo-info.html



-- 

hauke hoffmann service and electronic systems

Moristeig 60, D-23556 Lübeck

Telefon: +49 (0) 451 8896462
Fax: +49 (0) 451 8896461
Mobil: +49 (0) 170 7580491
E-Mail: office@hauke-hoffmann.net
PGP public key: www.hauke-hoffmann.net/static/pgp/kontakt.asc

^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: KVM performance
  2009-04-06 12:13 ` Hauke Hoffmann
  2009-04-06 16:30   ` AW: " BRAUN, Stefanie
@ 2009-04-07 12:58   ` BRAUN, Stefanie
  1 sibling, 0 replies; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-07 12:58 UTC (permalink / raw)
  To: kvm; +Cc: Hauke Hoffmann

Hi,
I'm not sure anymore if I really tested your suggested disk virtio setup yesterday,
because today the vmu does not start when using the virtio setup.

During boot time, the volgroup00 can not be found. 
At the moment I'm still searching why this error occurs.

working: -drive file=/images/vmu01.raw,index=0,media=disk,boot=on
not working: -drive file=/images/vmu01.raw,index=0,media=disk,boot=on,if=virtio
not working: -drive file=/images/vmu01.raw,boot=on,if=virtio

-----Ursprüngliche Nachricht-----
Von: Hauke Hoffmann [mailto:kontakt@hauke-hoffmann.net] 
Gesendet: Montag, 6. April 2009 14:13
An: kvm@vger.kernel.org
Cc: BRAUN, Stefanie
Betreff: Re: KVM performance

On Friday 03 April 2009 13:32:50 you wrote:
> Hallo,
>
> as I want to switch from XEN to KVM I've made some performance tests 
> to see if KVM is as peformant as XEN. But tests with a VMU that 
> receives a streamed video, adds a small logo to the video and streams 
> it to a client have shown that XEN performs much betten than KVM.
> In XEN the vlc (videolan client used to receive, process and send the
> video) process
> within the vmu has a cpuload of 33,8 % whereas in KVM the vlc process 
> has a cpuload of 99.9 %.
> I'am not sure why, does anybody now some settings to improve the KVM 
> performance?
>
> Thank you.
> Regards, Stefanie.
>
>
> Used hardware and settings:
> In the tests I've used the same host hardware for XEN and KVM:
> - Dual Core AMD 2.2 GHz, 8 GB RAM
> - Tested OSes for KVM Host: Fedora 10, 2.6.27.5-117.fc10.x86_64 with 
> kvm version 10.fc10 version 74
>                             also tested in january: compiled kernel 
> with
> kvm-83
>
> - KVM Guest settings: OS: Fedora 9 2.6.25-14.fc9.x86_64 (i386 also
> tested)
>                       RAM: 256 MB (same for XEN vmu)
>                       CPU: 1 Core with 2,2 GHz (same for XEN vmu)
> 			    tested nic models: rtl8139, e1000, virtio
>
> Tested Scenario: VMU receives a streamed video , adds a logo 
> (watermark) to the video stream and then streams it to a client
>
> Results:
>
> XEN:
> Host cpu load (virt-manager): 		23%
> VMU  cpu load (virt-manager):			18 %
> VLC process within VMU (top):			33,8%
>
> KVM:
> no virt-manager cpu load as I started the vmu with the kvm command
> Host cpu load :					52%
> qemu-kvm process (top)				77-100%
> VLC process within vmu (top):			80 - 99,9%
>
> KVM command to start vmu
> /usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 256 -net 
> nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10,model=virtio -net 
> tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/q
> em u-ifdown -vnc 127.0.0.1:1 -k de --daemonize

Hi Stefanie,

does vlc perform operations on disc (eg caching, logging, ...)? 

When it cache you can use virtio also for the disk. 
Just change
	-hda /images/vmu01.raw
to
	-drive file=/images/vmu01.raw,if=virtio,boot=on

Regards
Hauke


>
>
>
>
>
> ________________________________
>
> Alcatel-Lucent Deutschland AG
> Bell Labs Germany
> Service Infrastructure, ZFZ-SI
> Stefanie Braun
> Phone:   +49.711.821-34865
> Fax:     +49.711.821-32453
>
> Postal address:
> Alcatel-Lucent Deutschland AG
> Lorenzstrasse 10
> D-70435 STUTTGART
>
> Mail: stefanie.braun@alcatel-lucent.de
>
>
>
> Alcatel-Lucent Deutschland AG
> Sitz der Gesellschaft: Stuttgart - Amtsgericht Stuttgart HRB 4026 
> Vorsitzender des Aufsichtsrats: Michael Oppenhoff Vorstand: Alf Henryk 
> Wulf (Vors.), Dr. Rainer Fechner
>
> ________________________________
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in the 
> body of a message to majordomo@vger.kernel.org More majordomo info at  
> http://vger.kernel.org/majordomo-info.html



-- 

hauke hoffmann service and electronic systems

Moristeig 60, D-23556 Lübeck

Telefon: +49 (0) 451 8896462
Fax: +49 (0) 451 8896461
Mobil: +49 (0) 170 7580491
E-Mail: office@hauke-hoffmann.net
PGP public key: www.hauke-hoffmann.net/static/pgp/kontakt.asc

^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: AW: KVM performance
       [not found]     ` <49DA2F54.8090109@redhat.com>
@ 2009-04-07 17:00       ` BRAUN, Stefanie
  2009-04-07 17:34         ` Avi Kivity
  0 siblings, 1 reply; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-07 17:00 UTC (permalink / raw)
  To: kvm; +Cc: Avi Kivity

Hello,

I think that I've mixed the values in my first email for this topic and actually provided the values without network virtio enabled.
So the values for a kvm vmu with enabled virtio are indeed a little better but not as good as Xen.
At the moment I'm still working to get the virtio disk vmu setup working as I think it would be interesting how the performance values would improve.

All following tests have been executed using a vmu (ram 512 mb, 1 core 2,2 GHz) and the vlc (video player, that can f.e. stream, receive, transcode videos)

VMU setup for first performance values (without network virtio)
/usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 512 -net nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10 -net tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qemu-ifdown -net nic,vlan=1,macaddr=aa:bb:cc:dd:ee:11 -net tap,ifname=tap1,vlan=1,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qemu-ifdown -vnc 127.0.0.1:2 -k de --daemonize

VMU setup for second performance values (with network virtio)
/usr/bin/qemu-kvm -boot c -hda /images/vmu01.raw -m 512 -net nic,vlan=0,macaddr=aa:bb:cc:dd:ee:10,model=virtio -net tap,ifname=tap0,vlan=0,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qemu-ifdown -net nic,vlan=1,macaddr=aa:bb:cc:dd:ee:11,model=virtio -net tap,ifname=tap1,vlan=1,script=/etc/kvm/qemu-ifup,downscript=/etc/kvm/qemu-ifdown -vnc 127.0.0.1:2 -k de --daemonize



The first column of performance values show the VMU without virtio network, the second column with virtio network

1. Subtest: VLC reads video from local disk and streams it via udp to another pc
		Host performance: 		11% 		11%
            kvm process in host (top):	22%		22%
		vlc process in vmu (top): 	15%		7%

2. Subtest: Just receiving a video via udp  (no displaying as no X11 is installed on the vmu)
		Host performance: 		16% 		10%
            kvm process in host (top) :	30%		17%
		vlc process in vmu (top) : 	3%		3%


3. Subtest: Receiving a video via udp and saving it locally in a file
		Host performance: 		17% 		11%
            kvm process in host (top) : 	38%		24%
		vlc process in vmu (top) : 	12%		11%


4. Subtest: Reading video locally, adding a logo to the video stream and then saving the video locally
		Host performance: 		50% 		50%
            kvm process in host (top) : 	99%		99%
		vlc process in vmu (top) : 	99%		99%


5. Subtest: Receiving the video from pc 1 and at the same time streaming the received video to pc 2
		Host performance: 		23% 		18%
            kvm process in host (top) : 	22% 		35%
		vlc process in vmu (top) : 	48% 		10%

6. The originial test: receiving streamed video, adding a logo and the sending it to another pc
		Host performance: 		52% 			50%
            kvm process in host (top) : 	77-99% 		60-99% 	(for both most time 99%)
		vlc process in vmu (top) : 	80-99% 		50-99% 	(for both most time 99%)


I've have repeated almost all tests with XEN 

1. Subtest: VLC reads video from local disk and streams it via udp to another pc
		Host performance (Domain-0 + vmu)(virt-manager): 	4% 
            VMU (virt-manager) : 						2%
		vlc process in vmu (top) : 					1%

3. Subtest: Receiving a video via udp and saving it locally in a file
		Host performance (Domain-0 + vmu)(virt-manager): 	7% 
           VMU (virt-manager) : 						4%
		vlc process in vmu (top) : 					3%

4. Subtest: Reading video locally, adding a logo to the video stream and then saving the video locally		
		Host performance (Domain-0 + vmu)(virt-manager): 	3-55% 
            VMU (virt-manager) : 						0-50%
		vlc process in vmu (top) : 					14 -99% varies a lot 

5. Subtest: Receiving the video from pc 1 and at the same time streaming the received video to pc 2		
		Host performance (Domain-0 + vmu)(virt-manager): 	6% 
            VMU (virt-manager) : 						3%
		vlc process in vmu (top) : 					1%

6. The originial test: receiving streamed video, adding a logo and the sending it to another pc
		Host performance (Domain-0 + vmu)(virt-manager): 	23% 
            VMU (virt-manager) : 						18%
		vlc process in vmu (top) : 					33,8%


-----Ursprüngliche Nachricht-----
Von: Avi Kivity [mailto:avi@redhat.com] 
Gesendet: Montag, 6. April 2009 18:36
An: BRAUN, Stefanie
Betreff: Re: AW: KVM performance

BRAUN, Stefanie wrote:
> Is this a tcp test?
>
> Can you test receive and transmit separately?
>
> Hello,
>
> it's a "transcoder" test, but without transcoding between video 
> formats, the vmu just adds a logo (a watermark) into the video.
>
> At the same time the vmu performed several actions:
> - receiving a streamed video via udp
> - adding a logo to the video
> - sending the streamed video via udp
>
> But I think I can split up the test into the following subtests and 
> provide further performance values Sub test 1 receive:  - Receiving 
> the video from network (udp) and saving locally Sub test 2 transmit: - 
> Reading the video from local ressource and sending via network Sub test 3 process:  - Reading the video from local ressource, adding the logo to the video stream and saving it again locally.
>  
>   

We have a known issue with udp transmits, you might be hitting that.  
Please do separate your tests so we can see what the root cause is.

--
I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: AW: AW: KVM performance
  2009-04-07 17:00       ` AW: AW: " BRAUN, Stefanie
@ 2009-04-07 17:34         ` Avi Kivity
  2009-04-08 11:38           ` AW: " BRAUN, Stefanie
  0 siblings, 1 reply; 14+ messages in thread
From: Avi Kivity @ 2009-04-07 17:34 UTC (permalink / raw)
  To: BRAUN, Stefanie; +Cc: kvm

BRAUN, Stefanie wrote:
> 1. Subtest: VLC reads video from local disk and streams it via udp to another pc
> 		Host performance: 		11% 		11%
>             kvm process in host (top):	22%		22%
> 		vlc process in vmu (top): 	15%		7%
>
>   

While this isn't wonderful, it's not your major bottleneck now.  What's 
the bandwidth generated by the workload?

>
> 4. Subtest: Reading video locally, adding a logo to the video stream and then saving the video locally
> 		Host performance: 		50% 		50%
>             kvm process in host (top) : 	99%		99%
> 		vlc process in vmu (top) : 	99%		99%
>   

Now this is bad.  Please provide the output of 'kvm_stat -1' while this 
is running.  Also, describe the guest.  Is it Linux?  if so, i386 or 
x86_64?  and is CONFIG_HIGHMEM enabled?

UDP performance is a known issue now, and we are working on it.  TCP is 
much better due to segmentation offload.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: AW: AW: KVM performance
  2009-04-07 17:34         ` Avi Kivity
@ 2009-04-08 11:38           ` BRAUN, Stefanie
  2009-04-09 15:34             ` BRAUN, Stefanie
  0 siblings, 1 reply; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-08 11:38 UTC (permalink / raw)
  To: Avi Kivity; +Cc: kvm

[-- Attachment #1: Type: text/plain, Size: 1189 bytes --]


BRAUN, Stefanie wrote:
> 1. Subtest: VLC reads video from local disk and streams it via udp to
another pc
> 		Host performance: 		11% 		11%
>             kvm process in host (top):	22%		22%
> 		vlc process in vmu (top): 	15%		7%
>
>   

While this isn't wonderful, it's not your major bottleneck now.  What's
the bandwidth generated by the workload?

Generated Bandwidth : 6500 kbit per sec

>
> 4. Subtest: Reading video locally, adding a logo to the video stream
and then saving the video locally
> 		Host performance: 		50% 		50%
>             kvm process in host (top) : 	99%		99%
> 		vlc process in vmu (top) : 	99%		99%
>   

Now this is bad.  Please provide the output of 'kvm_stat -1' while this
is running.  Also, describe the guest.  Is it Linux?  if so, i386 or
x86_64?  and is CONFIG_HIGHMEM enabled?

Linux, Fedora 10, x86_64, (2.6.27.21-170.2.56.fc10.x86_64)
The config file does not contain a CONFIG_HIGHMEM parameter.

UDP performance is a known issue now, and we are working on it.  TCP is
much better due to segmentation offload.

--
I have a truly marvellous patch that fixes the bug which this signature
is too narrow to contain.


[-- Attachment #2: vmu01_stat --]
[-- Type: application/octet-stream, Size: 28557 bytes --]

 efer_relo      exits  fpu_reloa  halt_exit  halt_wake  host_stat  hypercall  insn_emul  insn_emul     invlpg   io_exits  irq_exits  irq_windo  largepage  mmio_exit  mmu_cache  mmu_flood  mmu_pde_z  mmu_pte_u  mmu_pte_w  mmu_recyc  mmu_shado  nmi_windo   pf_fixed   pf_guest  remote_tl  request_i  signal_ex  tlb_flush
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 efer_relo      exits  fpu_reloa  halt_exit  halt_wake  host_stat  hypercall  insn_emul  insn_emul     invlpg   io_exits  irq_exits  irq_windo  largepage  mmio_exit  mmu_cache  mmu_flood  mmu_pde_z  mmu_pte_u  mmu_pte_w  mmu_recyc  mmu_shado  nmi_windo   pf_fixed   pf_guest  remote_tl  request_i  signal_ex  tlb_flush
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         0       4413         82          0          0         85          0       2289          0          0         72       2014          0          0          9          0          0          0          0          0          0          0          0          0          0          0          0          0         28
         0       4112         28          0          0         92          0       2017          0          0         83       2010          0          0          0          0          0          0          0          0          0          0          0          0          0          0          0          0          4
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         0       4280         81          0          0        132          0       2019          0          0        130       2005          0          0          0          0          0          0          0          0          0          0          0        124          0          0          0          0          4
         0       4287         42          0          0        110          0       2017          0          0        104       1999          0          0          0          0          0          0          0          0          0          0          0        166          0          0          0          0          5
         0       4391         56          0          0        197          0       2030          0          0        187       2012          0          0          0          0          0          0          0          0          0          0          0        159          0          0          0          0          7
         0       4226         31          0          0         82          0       2022          0          0         78       2006          0          0          0          0          0          0          0          0          0          0          0        119          0          0          0          0          5
Traceback (most recent call last):
  File "./kvm_stat", line 124, in <module>
    log(stats)
  File "./kvm_stat", line 94, in log
    time.sleep(1)
KeyboardInterrupt

^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: AW: AW: KVM performance
  2009-04-08 11:38           ` AW: " BRAUN, Stefanie
@ 2009-04-09 15:34             ` BRAUN, Stefanie
  2009-04-11 16:19               ` Avi Kivity
  0 siblings, 1 reply; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-09 15:34 UTC (permalink / raw)
  To: Avi Kivity; +Cc: kvm

Hello,

now I was able to start the guest vmu with disk virtio, and some of the
tests with disk involvement even improved a bit.
But the test in which a logo is added to the video stream does not
improve. I don't know why the performance is so bad? 

Subtest: Reading video locally, adding a logo to the video stream and
then saving the video locally
		Host performance: 		50%
            kvm process in host (top) : 	99%
		vlc process in vmu (top) : 	99%


The output of kvm_stat -1 during the subtest is the following:

efer_reload                    0         0
exits                    9913473      3994
fpu_reload                393453         4
halt_exits                768222         0
halt_wakeup               497108         0
host_state_reload        3266556         4
hypercalls                508554         0
insn_emulation           5405007      1999
insn_emulation_fail            0         0
invlpg                         0         0
io_exits                 1879454         0
irq_exits                 568541      1995
irq_window                     0         0
largepages                     0         0
mmio_exits                145028         0
mmu_cache_miss             51455         0
mmu_flooded                40895         0
mmu_pde_zapped             34101         0
mmu_pte_updated           448719         0
mmu_pte_write             858494         0
mmu_recycled                   0         0
mmu_shadow_zapped          50590         0
nmi_window                     0         0
pf_fixed                  494176         0
pf_guest                  378754         0
remote_tlb_flush               0         0
request_irq                    0         0
signal_exits                   1         0
tlb_flush                1076949         1

The guest I've started 
has 512 MB RAM, 1 Core 2.2 GHz of the host which is a dual core machine.

Guest settings:       RAM: 512 MB 
                      CPU: 1 Core with 2,2 GHz
Tested i386 OS as well as x86_64 with same performance results.

			    OS: Fedora 10 i386;
2.6.27.21-170.2.56.fc10.i686
                          CONFIG_HIGHMEM=y
                          CONFIG_HIGHMEM4G=y

			    OS: Fedora 10 x86_64;
2.6.27.21-170.2.56.fc10.x86_64
                          The config file does not contain the HIGHMEM
parameter.

Host settings: 	OS: Fedora 10 x86_64; 2.6.27.5-117.fc10.x86_64
			KVM: Version 74 Release 10.fc10


Best regards,
Steffi






^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: AW: AW: AW: KVM performance
  2009-04-09 15:34             ` BRAUN, Stefanie
@ 2009-04-11 16:19               ` Avi Kivity
  2009-04-14  8:26                 ` AW: " BRAUN, Stefanie
  0 siblings, 1 reply; 14+ messages in thread
From: Avi Kivity @ 2009-04-11 16:19 UTC (permalink / raw)
  To: BRAUN, Stefanie; +Cc: kvm

BRAUN, Stefanie wrote:
> Hello,
>
> now I was able to start the guest vmu with disk virtio, and some of the
> tests with disk involvement even improved a bit.
> But the test in which a logo is added to the video stream does not
> improve. I don't know why the performance is so bad? 
>
> Subtest: Reading video locally, adding a logo to the video stream and
> then saving the video locally
> 		Host performance: 		50%
>             kvm process in host (top) : 	99%
> 		vlc process in vmu (top) : 	99%
>
>
> The output of kvm_stat -1 during the subtest is the following:
>
> efer_reload                    0         0
> exits                    9913473      3994
>   


This indicates that kvm is running in guest mode all of the time and is 
therefore quite efficient.  Perhaps the test uses sse instructions which 
kvm doesn't expose?  Try adding -cpu core2duo to the command line.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: AW: AW: AW: KVM performance
  2009-04-11 16:19               ` Avi Kivity
@ 2009-04-14  8:26                 ` BRAUN, Stefanie
  2009-04-14  8:47                   ` Avi Kivity
  0 siblings, 1 reply; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-14  8:26 UTC (permalink / raw)
  To: Avi Kivity; +Cc: kvm

Hello,
the host runs on a Dual-Core AMD Opteron Processor.
Does there exist a similar AMD parameter?

Regard Stefanie

-----Ursprüngliche Nachricht-----
Von: Avi Kivity [mailto:avi@redhat.com] 
Gesendet: Samstag, 11. April 2009 18:19
An: BRAUN, Stefanie
Cc: kvm@vger.kernel.org
Betreff: Re: AW: AW: AW: KVM performance

BRAUN, Stefanie wrote:
> Hello,
>
> now I was able to start the guest vmu with disk virtio, and some of 
> the tests with disk involvement even improved a bit.
> But the test in which a logo is added to the video stream does not 
> improve. I don't know why the performance is so bad?
>
> Subtest: Reading video locally, adding a logo to the video stream and 
> then saving the video locally
> 		Host performance: 		50%
>             kvm process in host (top) : 	99%
> 		vlc process in vmu (top) : 	99%
>
>
> The output of kvm_stat -1 during the subtest is the following:
>
> efer_reload                    0         0
> exits                    9913473      3994
>   


This indicates that kvm is running in guest mode all of the time and is therefore quite efficient.  Perhaps the test uses sse instructions which kvm doesn't expose?  Try adding -cpu core2duo to the command line.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: AW: AW: AW: AW: KVM performance
  2009-04-14  8:26                 ` AW: " BRAUN, Stefanie
@ 2009-04-14  8:47                   ` Avi Kivity
  2009-04-16 13:27                     ` AW: " BRAUN, Stefanie
  0 siblings, 1 reply; 14+ messages in thread
From: Avi Kivity @ 2009-04-14  8:47 UTC (permalink / raw)
  To: BRAUN, Stefanie; +Cc: kvm

BRAUN, Stefanie wrote:
> Hello,
> the host runs on a Dual-Core AMD Opteron Processor.
> Does there exist a similar AMD parameter?
>   

You can add individual host cpu features by using '-cpu 
qemu64,+feature', where feature is taken from the host /proc/cpuinfo.  
Do you know which cpu features the program can take advantage of?

Also please try replacing the constant 0x0007040600070406ULL in 
kernel/x86/svm.c with 0x0606060606060606ULL and see what happens (don't 
forget to reload the modules).

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* AW: AW: AW: AW: AW: KVM performance
  2009-04-14  8:47                   ` Avi Kivity
@ 2009-04-16 13:27                     ` BRAUN, Stefanie
  2009-04-16 14:40                       ` Avi Kivity
  0 siblings, 1 reply; 14+ messages in thread
From: BRAUN, Stefanie @ 2009-04-16 13:27 UTC (permalink / raw)
  To: Avi Kivity; +Cc: kvm

Hello,
I've compiled a new kernel v2.6.27-rc5 with the modified svm.c.
But the behaviour of the vlc process in the guest is still the same. 

I've exported additional cpu features to the guest, e.g. mmxext with kvm-84.
But no performance changes.

I was not able to export the cpu flags 3dnow and 3dnowext to the guest, no error but they are not visible in /proc/cpuinfo. Not sure why.

Regards Stefanie



BRAUN, Stefanie wrote:
> qemu-kvm -cpu ? only shows
> qemu64, qemu32, 486, pentium, pentium2, pentium3, athlon
>   

It can also take additional +feature or -feature parameters.

Oh, maybe kvm-84 doesn't have this support?  try http://userweb.kernel.org/~avi/kvm-85rc6/.


-----Ursprüngliche Nachricht-----
Von: Avi Kivity [mailto:avi@redhat.com] 
Gesendet: Dienstag, 14. April 2009 10:48
An: BRAUN, Stefanie
Cc: kvm@vger.kernel.org
Betreff: Re: AW: AW: AW: AW: KVM performance

BRAUN, Stefanie wrote:
> Hello,
> the host runs on a Dual-Core AMD Opteron Processor.
> Does there exist a similar AMD parameter?
>   

You can add individual host cpu features by using '-cpu qemu64,+feature', where feature is taken from the host /proc/cpuinfo.  
Do you know which cpu features the program can take advantage of?

Also please try replacing the constant 0x0007040600070406ULL in kernel/x86/svm.c with 0x0606060606060606ULL and see what happens (don't forget to reload the modules).

--
I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.


^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: AW: AW: AW: AW: AW: KVM performance
  2009-04-16 13:27                     ` AW: " BRAUN, Stefanie
@ 2009-04-16 14:40                       ` Avi Kivity
  0 siblings, 0 replies; 14+ messages in thread
From: Avi Kivity @ 2009-04-16 14:40 UTC (permalink / raw)
  To: BRAUN, Stefanie; +Cc: kvm

BRAUN, Stefanie wrote:
> Hello,
> I've compiled a new kernel v2.6.27-rc5 with the modified svm.c.
> But the behaviour of the vlc process in the guest is still the same. 
>
> I've exported additional cpu features to the guest, e.g. mmxext with kvm-84.
> But no performance changes.
>
> I was not able to export the cpu flags 3dnow and 3dnowext to the guest, no error but they are not visible in /proc/cpuinfo. Not sure why.
>
>   

Can you test on an intel host (relative performance host vs guest)?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.


^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2009-04-16 14:41 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2009-04-03 11:32 KVM performance BRAUN, Stefanie
2009-04-06 11:45 ` Avi Kivity
     [not found]   ` <133D9897FB9C5E4E9DF2779DC91E947C51834A@SLFSNX.rcs.alcatel-research.de>
     [not found]     ` <49DA2F54.8090109@redhat.com>
2009-04-07 17:00       ` AW: AW: " BRAUN, Stefanie
2009-04-07 17:34         ` Avi Kivity
2009-04-08 11:38           ` AW: " BRAUN, Stefanie
2009-04-09 15:34             ` BRAUN, Stefanie
2009-04-11 16:19               ` Avi Kivity
2009-04-14  8:26                 ` AW: " BRAUN, Stefanie
2009-04-14  8:47                   ` Avi Kivity
2009-04-16 13:27                     ` AW: " BRAUN, Stefanie
2009-04-16 14:40                       ` Avi Kivity
2009-04-06 12:13 ` Hauke Hoffmann
2009-04-06 16:30   ` AW: " BRAUN, Stefanie
2009-04-07 12:58   ` BRAUN, Stefanie

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