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On 06/27/2014 05:48 PM, kerwin wrote:<br>
<blockquote
cite="mid:9EDA6D9B-56A8-4690-B73C-1DF1A42D3E7F@gmail.com"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
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Hi,
<div><br>
</div>
<div>I am running OpenStack Cluster and use libvirt + cgroup to
limit vm’s performance</div>
<div><a moz-do-not-send="true"
href="https://wiki.openstack.org/InstanceResourceQuota">https://wiki.openstack.org/InstanceResourceQuota</a></div>
<div><br>
</div>
<div>What I am confusing is..</div>
<div><br>
</div>
<div>1. After running a vm instance with some croup limit applied,
I can’t find any related cgroup settings.</div>
</blockquote>
<br>
well, there are two kinds of iotune for vm instance storage.<br>
1. cgroup way:<br>
as <a class="moz-txt-link-freetext" href="http://libvirt.org/formatdomain.html#elementsBlockTuning">http://libvirt.org/formatdomain.html#elementsBlockTuning</a>
described,<br>
the <blkiotune> element should be configured under
<domain>.<br>
<br>
2. qemu way:<br>
For some reason, qemu provides block iotune, <br>
see <a class="moz-txt-link-freetext" href="http://libvirt.org/formatdomain.html#elementsDisks">http://libvirt.org/formatdomain.html#elementsDisks</a><br>
This capability you used is implemented inside qemu.<br>
<br>
<blockquote
cite="mid:9EDA6D9B-56A8-4690-B73C-1DF1A42D3E7F@gmail.com"
type="cite">
<div>2. Can I change limit value after instance is running? like
change disk_read_iops_sec from 10 to 20.</div>
<div><br>
</div>
<div>One of the xml file like below.</div>
<div><br>
</div>
<div>
<div><domain type="kvm"></div>
<div>
<uuid>27f49e5c-8ee0-4a09-8269-5fa31acd2983</uuid></div>
<div> <name>instance-000000da</name></div>
<div> <memory>2097152</memory></div>
<div> <vcpu cpuset="1-12">1</vcpu></div>
<div> <sysinfo type="smbios"></div>
<div> <system></div>
<div> <entry name="manufacturer">Red Hat
Inc.</entry></div>
<div> <entry name="product">OpenStack
Nova</entry></div>
<div> <entry
name="version">2013.2.3-1.el6</entry></div>
<div> <entry
name="serial">9fa4736a-2b02-11e1-a8e4-5cf3fcb968b4</entry></div>
<div> <entry
name="uuid">27f49e5c-8ee0-4a09-8269-5fa31acd2983</entry></div>
<div> </system></div>
<div> </sysinfo></div>
<div> <os></div>
<div> <type>hvm</type></div>
<div> <boot dev="hd"/></div>
<div> <smbios mode="sysinfo"/></div>
<div> </os></div>
<div> <features></div>
<div> <acpi/></div>
<div> <apic/></div>
<div> </features></div>
<div> <clock offset="utc"></div>
<div> <timer name="pit" tickpolicy="delay"/></div>
<div> <timer name="rtc" tickpolicy="catchup"/></div>
<div> </clock></div>
<div> <cpu mode="host-model" match="exact"/></div>
<div> <devices></div>
<div> <disk type="file" device="disk"></div>
<div> <driver name="qemu" type="qcow2" cache="none"/></div>
<div> <source
file="/data1/lib/nova/instances/27f49e5c-8ee0-4a09-8269-5fa31acd2983/disk"/></div>
<div> <target bus="virtio" dev="vda"/></div>
<div> <iotune></div>
<div>
<read_bytes_sec>25600000</read_bytes_sec></div>
<div>
<write_bytes_sec>40960000</write_bytes_sec></div>
<div> </iotune></div>
<div> </disk></div>
<div> <interface type="bridge"></div>
<div> <mac address="fa:16:3e:49:04:ce"/></div>
<div> <model type="virtio"/></div>
<div> <source bridge="br-int"/></div>
<div> <target dev="tape30b3c05-12"/></div>
<div> <virtualport type="openvswitch"></div>
<div> <parameters
interfaceid="e30b3c05-126c-45bd-ac31-e5eb5481a652"/></div>
<div> </virtualport></div>
<div> </interface></div>
<div> <serial type="file"></div>
<div> <source
path="/data1/lib/nova/instances/27f49e5c-8ee0-4a09-8269-5fa31acd2983/console.log"/></div>
<div> </serial></div>
<div> <serial type="pty"/></div>
<div> <input type="tablet" bus="usb"/></div>
<div> <graphics type="vnc" autoport="yes" keymap="en-us"
listen="10.13.128.43"/></div>
<div> </devices></div>
<div></domain></div>
</div>
<div><br>
<div>
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<div style="orphans: 2; widows: 2;">✉ --</div>
<div style="orphans: 2; widows: 2;">朴元奎</div>
<div style="orphans: 2; widows: 2;">kerwin</div>
</div>
</div>
<br>
</div>
<br>
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