diff options
| author | Hu Tao <hutao@cn.fujitsu.com> | 2014-09-10 17:05:49 +0800 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2014-09-12 15:43:06 +0200 |
| commit | 0e4271b711a8ea766d29824c844e268b91ac3ae5 (patch) | |
| tree | 8d00320ff6821eca68094864906838f3f4f5a6fe /qemu-img.texi | |
| parent | 06247428be8037b3739280f82cb29efe8397695f (diff) | |
qcow2: Add falloc and full preallocation option
preallocation=falloc allocates disk space by posix_fallocate(),
preallocation=full allocates disk space by writing zeros to disk.
Both modes imply preallocation=metadata.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qemu-img.texi')
| -rw-r--r-- | qemu-img.texi | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/qemu-img.texi b/qemu-img.texi index d64d05edda..50d2cca7a0 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -476,9 +476,11 @@ sizes can improve the image file size whereas larger cluster sizes generally provide better performance. @item preallocation -Preallocation mode (allowed values: off, metadata). An image with preallocated -metadata is initially larger but can improve performance when the image needs -to grow. +Preallocation mode (allowed values: @code{off}, @code{metadata}, @code{falloc}, +@code{full}). An image with preallocated metadata is initially larger but can +improve performance when the image needs to grow. @code{falloc} and @code{full} +preallocations are like the same options of @code{raw} format, but sets up +metadata also. @item lazy_refcounts If this option is set to @code{on}, reference count updates are postponed with |