mirror: add buf-size argument to drive-mirror

This makes sense when the next commit starts using the extra buffer space
to perform many I/O operations asynchronously.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Paolo Bonzini 2013-01-22 09:03:13 +01:00 committed by Kevin Wolf
parent bd48bde8f0
commit 08e4ed6cde
8 changed files with 56 additions and 12 deletions

View File

@ -207,7 +207,7 @@ static void coroutine_fn mirror_run(void *opaque)
if (backing_filename[0] && !s->target->backing_hd) {
bdrv_get_info(s->target, &bdi);
if (s->granularity < bdi.cluster_size) {
s->buf_size = bdi.cluster_size;
s->buf_size = MAX(s->buf_size, bdi.cluster_size);
length = (bdrv_getlength(bs) + s->granularity - 1) / s->granularity;
s->cow_bitmap = bitmap_new(length);
}
@ -416,8 +416,8 @@ static BlockJobType mirror_job_type = {
};
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
int64_t speed, int64_t granularity, MirrorSyncMode mode,
BlockdevOnError on_source_error,
int64_t speed, int64_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockDriverCompletionFunc *cb,
void *opaque, Error **errp)
@ -455,7 +455,7 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target,
s->target = target;
s->mode = mode;
s->granularity = granularity;
s->buf_size = granularity;
s->buf_size = MAX(buf_size, granularity);
bdrv_set_dirty_tracking(bs, granularity);
bdrv_set_enable_write_cache(s->target, true);

View File

@ -1188,12 +1188,15 @@ void qmp_block_commit(const char *device,
drive_get_ref(drive_get_by_blockdev(bs));
}
#define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
void qmp_drive_mirror(const char *device, const char *target,
bool has_format, const char *format,
enum MirrorSyncMode sync,
bool has_mode, enum NewImageMode mode,
bool has_speed, int64_t speed,
bool has_granularity, uint32_t granularity,
bool has_buf_size, int64_t buf_size,
bool has_on_source_error, BlockdevOnError on_source_error,
bool has_on_target_error, BlockdevOnError on_target_error,
Error **errp)
@ -1222,6 +1225,10 @@ void qmp_drive_mirror(const char *device, const char *target,
if (!has_granularity) {
granularity = 0;
}
if (!has_buf_size) {
buf_size = DEFAULT_MIRROR_BUF_SIZE;
}
if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
error_set(errp, QERR_INVALID_PARAMETER, device);
return;
@ -1311,7 +1318,7 @@ void qmp_drive_mirror(const char *device, const char *target,
return;
}
mirror_start(bs, target_bs, speed, granularity, sync,
mirror_start(bs, target_bs, speed, granularity, buf_size, sync,
on_source_error, on_target_error,
block_job_cb, bs, &local_err);
if (local_err != NULL) {

2
hmp.c
View File

@ -796,7 +796,7 @@ void hmp_drive_mirror(Monitor *mon, const QDict *qdict)
qmp_drive_mirror(device, filename, !!format, format,
full ? MIRROR_SYNC_MODE_FULL : MIRROR_SYNC_MODE_TOP,
true, mode, false, 0, false, 0,
true, mode, false, 0, false, 0, false, 0,
false, 0, false, 0, &errp);
hmp_handle_error(mon, &errp);
}

View File

@ -345,6 +345,7 @@ void commit_start(BlockDriverState *bs, BlockDriverState *base,
* @target: Block device to write to.
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
* @granularity: The chosen granularity for the dirty bitmap.
* @buf_size: The amount of data that can be in flight at one time.
* @mode: Whether to collapse all images in the chain to the target.
* @on_source_error: The action to take upon error reading from the source.
* @on_target_error: The action to take upon error writing to the target.
@ -358,8 +359,8 @@ void commit_start(BlockDriverState *bs, BlockDriverState *base,
* @bs will be switched to read from @target.
*/
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
int64_t speed, int64_t granularity, MirrorSyncMode mode,
BlockdevOnError on_source_error,
int64_t speed, int64_t granularity, int64_t buf_size,
MirrorSyncMode mode, BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
BlockDriverCompletionFunc *cb,
void *opaque, Error **errp);

View File

@ -1641,6 +1641,9 @@
# are smaller than that, else the cluster size. Must be a
# power of 2 between 512 and 64M (since 1.4).
#
# @buf-size: #optional maximum amount of data in flight from source to
# target (since 1.4).
#
# @on-source-error: #optional 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 (see BlockInfo).
@ -1658,7 +1661,7 @@
'data': { 'device': 'str', 'target': 'str', '*format': 'str',
'sync': 'MirrorSyncMode', '*mode': 'NewImageMode',
'*speed': 'int', '*granularity': 'uint32',
'*on-source-error': 'BlockdevOnError',
'*buf-size': 'int', '*on-source-error': 'BlockdevOnError',
'*on-target-error': 'BlockdevOnError' } }
##

View File

@ -939,7 +939,7 @@ EQMP
.name = "drive-mirror",
.args_type = "sync:s,device:B,target:s,speed:i?,mode:s?,format:s?,"
"on-source-error:s?,on-target-error:s?,"
"granularity:i?",
"granularity:i?,buf-size:i?",
.mhandler.cmd_new = qmp_marshal_input_drive_mirror,
},
@ -964,6 +964,8 @@ Arguments:
- "speed": maximum speed of the streaming job, in bytes per second
(json-int)
- "granularity": granularity of the dirty bitmap, in bytes (json-int, optional)
- "buf_size": maximum amount of data in flight from source to target, in bytes
(json-int, default 10M)
- "sync": what parts of the disk image should be copied to the destination;
possibilities include "full" for all the disk, "top" for only the sectors
allocated in the topmost image, or "none" to only replicate new I/O

View File

@ -207,6 +207,37 @@ class TestSingleDrive(ImageMirroringTestCase):
self.assertTrue(self.compare_images(test_img, target_img),
'target image does not match source after mirroring')
def test_small_buffer(self):
self.assert_no_active_mirrors()
# A small buffer is rounded up automatically
result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
buf_size=4096, target=target_img)
self.assert_qmp(result, 'return', {})
self.complete_and_wait()
result = self.vm.qmp('query-block')
self.assert_qmp(result, 'return[0]/inserted/file', target_img)
self.vm.shutdown()
self.assertTrue(self.compare_images(test_img, target_img),
'target image does not match source after mirroring')
def test_small_buffer2(self):
self.assert_no_active_mirrors()
qemu_img('create', '-f', iotests.imgfmt, '-o', 'cluster_size=%d,size=%d'
% (TestSingleDrive.image_len, TestSingleDrive.image_len), target_img)
result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
buf_size=65536, mode='existing', target=target_img)
self.assert_qmp(result, 'return', {})
self.complete_and_wait()
result = self.vm.qmp('query-block')
self.assert_qmp(result, 'return[0]/inserted/file', target_img)
self.vm.shutdown()
self.assertTrue(self.compare_images(test_img, target_img),
'target image does not match source after mirroring')
def test_large_cluster(self):
self.assert_no_active_mirrors()

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@ -1,5 +1,5 @@
....................
......................
----------------------------------------------------------------------
Ran 20 tests
Ran 22 tests
OK