On 10/29/2012 04:36 AM, Kevin Wolf wrote: > And this is where the copy occurs: qcow2 is organised in clusters, in > our example with the default 64k cluster size. A cluster can only be > allocated or unallocated as a whole. Now that we're allocating 64k in > sn1.qcow2, but have only 4k to write from our write request, the > remaining 60k must be copied from the backing file so that reading them > gives the same result as before.
Eureka! Thanks Kevin! Now the COW part makes total sense! I searched the web for this (prior to sending this question) and believe me, I couldn't find it this relationship (the name and how the cluster handling works). Many many thanks! -- Jorge _______________________________________________ virt mailing list [email protected] https://admin.fedoraproject.org/mailman/listinfo/virt
