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<div><span></span>Hello:</div><div> I am using openstack + libvirt + qemu-kvm. The speed of copying files between virtual machines <span style="font-family: 'Tahoma, Arial, ËÎÌå, '; font-size: 10.5pt; line-height: 1.5; background-color: window;">exceeds 300M Byte per second but the speed of dd command:</span></div><div><div> "watch dd oflag=direct,nonblock if=/dev/zero of=/opt/iotest1 bs=4M count=10" is around 20M byte per second. Every guest is the same, and there is no io tuning in libvirt. What can I do to unleash the speed of disk io speed inside the guest? </div><div><span style="color: rgb(0, 0, 0); background-color: rgba(0, 0, 0, 0);"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 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rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> </span><span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;"> Thanks!</span></div><div><br></div><div>The libvirt vm xml is as follow:</div></div><div><br></div><div><span style="color: rgb(0, 0, 0); background-color: rgba(0, 0, 0, 0);"><domain type='kvm' id='446'><br> <name>instance-00000663</name><br> <uuid>d9bda7d7-f68a-45ea-84a1-f50faa44b801</uuid><br> <metadata><br> <nova:instance xmlns:nova="http://openstack.org/xmlns/libvirt/nova/1.0"><br> <nova:package version="13.1.0-1.el7"/><br> <nova:name>smtestiotune</nova:name><br> <nova:creationTime>2017-08-23 07:38:13</nova:creationTime><br> <nova:flavor name="1VCPU_1G-RAM_50G-DISK"><br> <nova:memory>1024</nova:memory><br> <nova:disk>50</nova:disk><br> <nova:swap>0</nova:swap><br> <nova:ephemeral>0</nova:ephemeral><br> <nova:vcpus>1</nova:vcpus><br> </nova:flavor><br> <nova:owner><br> <nova:user uuid="cbcec503badc4a4191048b6e948bd926">admin</nova:user><br> <nova:project uuid="160b6ae5b7a645879d5e1fbd67693e8e">admin</nova:project><br> </nova:owner><br> <nova:root type="image" uuid="34714b12-281e-4180-8a6b-d6cd90c40d9c"/><br> </nova:instance><br> </metadata><br> <memory unit='KiB'>1048576</memory><br> <currentMemory unit='KiB'>1048576</currentMemory><br> <vcpu placement='static'>1</vcpu><br> <cputune><br> <shares>1024</shares><br> </cputune><br> <resource><br> <partition>/machine</partition><br> </resource><br> <sysinfo type='smbios'><br> <system><br> <entry name='manufacturer'>Fedora Project</entry><br> <entry name='product'>OpenStack Nova</entry><br> <entry name='version'>13.1.0-1.el7</entry><br> <entry name='serial'>0994820c-3e23-4cc0-9b2c-f34fb88dee4e</entry><br> <entry name='uuid'>d9bda7d7-f68a-45ea-84a1-f50faa44b801</entry><br> <entry name='family'>Virtual Machine</entry><br> </system><br> </sysinfo><br> <os><br> <type arch='x86_64' machine='pc-i440fx-rhel7.2.0'>hvm</type><br> <boot dev='hd'/><br> <smbios mode='sysinfo'/><br> </os><br> <features><br> <acpi/><br> <apic/><br> </features><br> <cpu mode='host-model'><br> <model fallback='allow'/><br> <topology sockets='1' cores='1' threads='1'/><br> </cpu><br> <clock offset='utc'><br> <timer name='pit' tickpolicy='delay'/><br> <timer name='rtc' tickpolicy='catchup'/><br> <timer name='hpet' present='no'/><br> </clock><br> <on_poweroff>destroy</on_poweroff><br> <on_reboot>restart</on_reboot><br> <on_crash>destroy</on_crash><br> <devices><br> <emulator>/usr/libexec/qemu-kvm</emulator><br> <disk type='network' device='disk'><br> <driver name='qemu' type='raw' cache='none'/><br> <source protocol='rbd' name='volumes/d9bda7d7-f68a-45ea-84a1-f50faa44b801_disk'><br> <host name='172.23.1.201' port='6789'/><br> <host name='172.23.1.202' port='6789'/><br> <host name='172.23.1.203' port='6789'/><br> </source><br> <backingStore/><br> <target dev='vda' bus='virtio'/><br> <alias name='virtio-disk0'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/><br> </disk><br> <controller type='usb' index='0'><br> <alias name='usb'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/><br> </controller><br> <controller type='pci' index='0' model='pci-root'><br> <alias name='pci.0'/><br> </controller><br> <controller type='virtio-serial' index='0'><br> <alias name='virtio-serial0'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/><br> </controller><br> <interface type='bridge'><br> <mac address='fa:16:3e:54:d9:9f'/><br> <source bridge='qbr74234353-83'/><br> <target dev='tap74234353-83'/><br> <model type='virtio'/><br> <alias name='net0'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/><br> </interface><br> <serial type='file'><br> <source path='/var/lib/nova/instances/d9bda7d7-f68a-45ea-84a1-f50faa44b801/console.log'/><br> <target port='0'/><br> <alias name='serial0'/><br> </serial><br> <serial type='pty'><br> <source path='/dev/pts/4'/><br> <target port='1'/><br> <alias name='serial1'/><br> </serial><br> <console type='file'><br> <source path='/var/lib/nova/instances/d9bda7d7-f68a-45ea-84a1-f50faa44b801/console.log'/><br> <target type='serial' port='0'/><br> <alias name='serial0'/><br> </console><br> <channel type='unix'><br> <source mode='bind' path='/var/lib/libvirt/qemu/org.qemu.guest_agent.0.instance-00000663.sock'/><br> <target type='virtio' name='org.qemu.guest_agent.0' state='connected'/><br> <alias name='channel0'/><br> <address type='virtio-serial' controller='0' bus='0' port='1'/><br> </channel><br> <input type='tablet' bus='usb'><br> <alias name='input0'/><br> </input><br> <input type='mouse' bus='ps2'/><br> <input type='keyboard' bus='ps2'/><br> <graphics type='vnc' port='5901' autoport='yes' listen='0.0.0.0' keymap='en-us'><br> <listen type='address' address='0.0.0.0'/><br> </graphics><br> <video><br> <model type='cirrus' vram='16384' heads='1'/><br> <alias name='video0'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/><br> </video><br> <memballoon model='virtio'><br> <stats period='10'/><br> <alias name='balloon0'/><br> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/><br> </memballoon><br> </devices><br></domain></span></div>
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<div><span><div style="MARGIN: 10px; FONT-FAMILY: verdana; FONT-SIZE: 10pt"><div>chagg@foxmail.com</div></div></span></div>
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