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<p class="MsoNormal">Hello all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I ran tests under the following settings to measure the IO performance of MySQL database. I used Sysbench as the client workload generator. I found that the performance of MySQL (both resource utilization and application)
has degraded by more than 50% after switching from setting a) to setting b). <o:p>
</o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Setting a): Controller & Compute node OS - Ubuntu 12.04, cloud software: OpenStack Havana, networking: nova-network, Hypervisor: KVM, Libvirt version: 1.1.1, QEMU version: 1.5.0, Host disk write cache: enabled, Guest
disk cache: none and host OS scheduler: CFQ.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Setting b): Controller & Compute node OS - Ubuntu 14.04, cloud software: OpenStack Icehouse, networking: Neutron, Hypervisor: KVM, Libvirt version: 1.2.2, QEMU version: 2.0.0, Host disk write cache: enabled, Guest disk
cache: none and host OS scheduler: CFQ.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">May I know has anybody performed such tests and if yes, can you please share details on the IO performance of VMs and the application?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I don’t know whether is the right question to ask in this forum. Can somebody share information at a high level about the improvements made in Libvirt (from version 1.1.1 to 1.2.2) for handling IO requests?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Krishnaprasad<o:p></o:p></span></p>
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