mirror of https://github.com/proxmox/mirror_qemu
a35e1c177d
This introduces a qemu-img create option for qcow2 which allows the metadata to be preallocated, i.e. clusters are reserved in the refcount table and L1/L2 tables, but no data is written to them. Metadata is quite small, so this happens in almost no time. Especially with qcow2 on virtio this helps to gain a bit of performance during the initial writes. However, as soon as create a snapshot, we're back to the normal slow speed, obviously. So this isn't the real fix, but kind of a cheat while we're still having trouble with qcow2 on virtio. Note that the option is disabled by default and needs to be specified explicitly using qemu-img create -f qcow2 -o preallocation=metadata. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> |
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| .. | ||
| bochs.c | ||
| cloop.c | ||
| cow.c | ||
| curl.c | ||
| dmg.c | ||
| nbd.c | ||
| parallels.c | ||
| qcow.c | ||
| qcow2-cluster.c | ||
| qcow2-refcount.c | ||
| qcow2-snapshot.c | ||
| qcow2.c | ||
| qcow2.h | ||
| raw-posix.c | ||
| raw-win32.c | ||
| vdi.c | ||
| vmdk.c | ||
| vpc.c | ||
| vvfat.c | ||