On 10/09/13 18:38, Daniel P. Berrange wrote:
On Wed, Oct 09, 2013 at 06:31:32PM +0200, Peter Krempa wrote:
The regular save image code has the support to compress images using a specified algorithm. This was not implemented for external checkpoints although it shares most of the backend code.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1017227 --- src/qemu/qemu.conf | 6 ++++++ src/qemu/qemu_conf.c | 1 + src/qemu/qemu_conf.h | 1 + src/qemu/qemu_driver.c | 23 +++++++++++++++++++++-- 4 files changed, 29 insertions(+), 2 deletions(-)
diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf index 7cf67df..aff5e6d 100644 --- a/src/qemu/qemu.conf +++ b/src/qemu/qemu.conf @@ -283,9 +283,15 @@ # specified format isn't valid, or the requested compression program can't be # found. # +# snapshot_image_format specifies the compression algorithm of the memory save +# image when an external snapshot of a domain is taken. This does not apply +# on disk image format. It is an error if the specified format isn't valid, +# or the requested compression program can't be found. +# #save_image_format = "raw" #dump_image_format = "raw" #managedsave_image_format = "raw" +#snapshot_image_format = "raw"
Same question here as previous patch. A snapshot is really just another form of saved image.
Here I have a bit stronger opinion compared to the managedsave case. I really think that users might prefer different settings for snapshots especially that snapshots can be created with a live guest, where a compression algorithm may inhibit successful finish of creating a snapshot as the migration procedure will be too slow to accomodate changing a lot of pages in the guest memory. Thus it might be desired to store snapshots uncompressed or just with a quick algorithm. The second option would be to disable compression for live snapshots, but that might be unfortunate too.
Daniel
Peter