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Nux commented on CLOUDSTACK-6369: --------------------------------- Hi, In case of ROOT volumes, can you confirm the cluster_size is inherited from the backing qcow2? If yes, then this will be important when we create templates. > Qcow2's cluster_size option support > ----------------------------------- > > Key: CLOUDSTACK-6369 > URL: https://issues.apache.org/jira/browse/CLOUDSTACK-6369 > Project: CloudStack > Issue Type: Improvement > Security Level: Public(Anyone can view this level - this is the > default.) > Components: KVM > Reporter: Yoshikazu Nojima > Assignee: Yoshikazu Nojima > Priority: Minor > Fix For: Future > > > To improve the qcow2 performance, it is important to tune parameters of > "qemu-img create" command. > preallocation=metadata option, which I am working on in CLOUDSTACK-6191 > improves randam IOPS well, but the qcow2 image created with > preallocation=metadata option cannot be used for a differential image. > This "cluster_size" option improves IOPS of a differential qcow2 image which > is created with preallocation=off. -- This message was sent by Atlassian JIRA (v6.2#6252)