diff options
| author | Pavel Butsykin <pbutsykin@virtuozzo.com> | 2016-07-22 11:17:52 +0300 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2016-09-05 19:06:48 +0200 |
| commit | 13b9414b5798539e2dbb87a570d96184fe21edf4 (patch) | |
| tree | b78f6ea0b47ef741ec29787c15fe57edf2b98dcc /qmp-commands.hx | |
| parent | dc7a4a9ed170c19b4036cef2720d3e8fb551cc0f (diff) | |
drive-backup: added support for data compression
The idea is simple - backup is "written-once" data. It is written block
by block and it is large enough. It would be nice to save storage
space and compress it.
The patch adds a flag to the qmp/hmp drive-backup command which enables
block compression. Compression should be implemented in the format driver
to enable this feature.
There are some limitations of the format driver to allow compressed writes.
We can write data only once. Though for backup this is perfectly fine.
These limitations are maintained by the driver and the error will be
reported if we are doing something wrong.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qmp-commands.hx')
| -rw-r--r-- | qmp-commands.hx | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/qmp-commands.hx b/qmp-commands.hx index 956f1b0f47..d1593c91ff 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -1217,7 +1217,8 @@ EQMP { .name = "drive-backup", .args_type = "job-id:s?,sync:s,device:B,target:s,speed:i?,mode:s?," - "format:s?,bitmap:s?,on-source-error:s?,on-target-error:s?", + "format:s?,bitmap:s?,compress:b?," + "on-source-error:s?,on-target-error:s?", .mhandler.cmd_new = qmp_marshal_drive_backup, }, @@ -1253,6 +1254,8 @@ Arguments: - "mode": whether and how QEMU should create a new image (NewImageMode, optional, default 'absolute-paths') - "speed": the maximum speed, in bytes per second (json-int, optional) +- "compress": true to compress data, if the target format supports it. + (json-bool, optional, default false) - "on-source-error": the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status. |