mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
69f47505ee
qemu/block
History
Vladimir Sementsov-Ogievskiy 69f47505ee block: avoid recursive block_status call if possible 
drv_co_block_status digs bs->file for additional, more accurate search
for hole inside region, reported as DATA by bs since 5daa74a6eb.

This accuracy is not free: assume we have qcow2 disk. Actually, qcow2
knows, where are holes and where is data. But every block_status
request calls lseek additionally. Assume a big disk, full of
data, in any iterative copying block job (or img convert) we'll call
lseek(HOLE) on every iteration, and each of these lseeks will have to
iterate through all metadata up to the end of file. It's obviously
ineffective behavior. And for many scenarios we don't need this lseek
at all.

However, lseek is needed when we have metadata-preallocated image.

So, let's detect metadata-preallocation case and don't dig qcow2's
protocol file in other cases.

The idea is to compare allocation size in POV of filesystem with
allocations size in POV of Qcow2 (by refcounts). If allocation in fs is
significantly lower, consider it as metadata-preallocation case.

102 iotest changed, as our detector can't detect shrinked file as
metadata-preallocation, which don't seem to be wrong, as with metadata
preallocation we always have valid file length.

Two other iotests have a slight change in their QMP output sequence:
Active 'block-commit' returns earlier because the job coroutine yields
earlier on a blocking operation. This operation is loading the refcount
blocks in qcow2_detect_metadata_preallocation().

Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04 15:20:41 +02:00
..
accounting.c block/accounting: introduce latency histogram 2018-03-19 14:58:37 -05:00
backup.c block/backup: refactor: split out backup_calculate_cluster_size 2019-05-28 20:30:55 +02:00
blkdebug.c block: Advertise BDRV_REQ_NO_FALLBACK in filter drivers 2019-03-26 11:37:51 +01:00
blklogwrites.c block: Purify .bdrv_refresh_filename() 2019-02-25 15:11:27 +01:00
blkreplay.c trivial: Make bios files and source files non-executable 2018-09-25 17:26:18 +02:00
blkverify.c block: Purify .bdrv_refresh_filename() 2019-02-25 15:11:27 +01:00
block-backend.c block: Make bdrv_root_attach_child() unref child_bs on failure 2019-05-28 20:30:55 +02:00
bochs.c avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
cloop.c block: Require auto-read-only for existing fallbacks 2018-11-05 15:09:55 +01:00
commit.c commit: Use bdrv_append() in commit_start() 2019-05-07 17:14:21 +02:00
copy-on-read.c block: Advertise BDRV_REQ_NO_FALLBACK in filter drivers 2019-03-26 11:37:51 +01:00
create.c jobs: utilize job_exit shim 2018-08-31 16:28:33 +02:00
crypto.c block: Make bdrv_{copy_on_read,crypto_luks,replication} static 2019-03-19 15:49:29 +01:00
crypto.h Clean up ill-advised or unusual header guards 2019-05-13 08:58:55 +02:00
curl.c block/curl: Implement bdrv_refresh_filename() 2019-02-25 15:11:27 +01:00
dirty-bitmap.c qapi: support external bitmaps in block-dirty-bitmap-merge 2019-05-28 19:33:31 -04:00
dmg-bz2.c dmg: Move libbz2 code to dmg-bz2.so 2016-10-07 14:14:06 +02:00
dmg-lzfse.c block: adding lzfse decompressing support as a module. 2018-12-14 11:52:40 +01:00
dmg.c dmg: don't skip zero chunk 2019-01-04 11:15:09 +00:00
dmg.h dmg: including dmg-lzfse module inside dmg block driver. 2018-12-14 11:52:40 +01:00
file-posix.c block/file-posix: Unaligned O_DIRECT block-status 2019-05-20 17:08:57 +02:00
file-win32.c avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
gluster.c block/gluster: limit the transfer size to 512 MiB 2019-04-02 12:04:44 +02:00
io.c block: avoid recursive block_status call if possible 2019-06-04 15:20:41 +02:00
iscsi-opts.c Move include qemu/option.h from qemu-common.h to actual users 2018-02-09 13:52:16 +01:00
iscsi.c block/iscsi: Restrict Linux-specific code 2019-03-11 16:33:49 +01:00
linux-aio.c avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
Makefile.objs qcow2: add separate file for threaded data processing functions 2019-05-28 20:30:55 +02:00
mirror.c blockjob: Propagate AioContext change to all job nodes 2019-05-20 17:08:56 +02:00
nbd-client.c nbd/client: Trace server noncompliance on structured reads 2019-04-01 08:58:04 -05:00
nbd-client.h nbd: Restrict connection_co reentrance 2019-02-25 15:03:19 +01:00
nbd.c nbd/client: Lower min_block for block-status, unaligned size 2019-03-30 20:52:19 -05:00
nfs.c block: Purify .bdrv_refresh_filename() 2019-02-25 15:11:27 +01:00
null.c block/null: Generate filename even with latency-ns 2019-02-25 15:11:27 +01:00
nvme.c block/nvme: Fix bdrv_refresh_filename() 2019-02-25 15:11:27 +01:00
parallels.c block/parallels: use buffer-based io 2019-04-30 15:29:00 +02:00
parallels.h Clean up includes 2018-02-09 05:05:11 +01:00
qapi.c qemu-img: Saner printing of large file sizes 2019-04-30 15:29:00 +02:00
qcow2-bitmap.c qcow2-bitmap: initialize bitmap directory alignment 2019-05-28 20:30:55 +02:00
qcow2-cache.c qcow2.h: add missing include 2019-05-28 20:30:55 +02:00
qcow2-cluster.c qcow2: skip writing zero buffers to empty COW areas 2019-05-28 20:30:55 +02:00
qcow2-refcount.c block: avoid recursive block_status call if possible 2019-06-04 15:20:41 +02:00
qcow2-snapshot.c qcow2.h: add missing include 2019-05-28 20:30:55 +02:00
qcow2-threads.c qcow2: do encryption in threads 2019-05-28 20:30:55 +02:00
qcow2.c block: avoid recursive block_status call if possible 2019-06-04 15:20:41 +02:00
qcow2.h block: avoid recursive block_status call if possible 2019-06-04 15:20:41 +02:00
qcow.c block/qcow: use buffer-based io 2019-04-30 15:29:00 +02:00
qed-check.c block/qed: add missed coroutine_fn markers 2019-04-30 15:29:00 +02:00
qed-cluster.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-l2-cache.c qed: protect table cache with CoMutex 2017-07-17 11:34:11 +08:00
qed-table.c block/qed: add missed coroutine_fn markers 2019-04-30 15:29:00 +02:00
qed.c block/qed: add missed coroutine_fn markers 2019-04-30 15:29:00 +02:00
qed.h block/qed: add missed coroutine_fn markers 2019-04-30 15:29:00 +02:00
quorum.c block: Make bdrv_root_attach_child() unref child_bs on failure 2019-05-28 20:30:55 +02:00
raw-format.c block: Advertise BDRV_REQ_NO_FALLBACK in filter drivers 2019-03-26 11:37:51 +01:00
rbd.c block: Add strong_runtime_opts to BlockDriver 2019-02-25 15:11:27 +01:00
replication.c block: Make bdrv_{copy_on_read,crypto_luks,replication} static 2019-03-19 15:49:29 +01:00
sheepdog.c block: Add strong_runtime_opts to BlockDriver 2019-02-25 15:11:27 +01:00
snapshot.c block/snapshot: remove bdrv_snapshot_delete_by_id_or_name 2019-02-25 15:03:18 +01:00
ssh.c block/ssh: Implement .bdrv_dirname() 2019-05-07 17:14:21 +02:00
stream.c block/stream: use buffer-based io 2019-04-30 15:29:00 +02:00
throttle-groups.c throttle-groups: fix restart coroutine iothread race 2019-01-24 10:02:28 +00:00
throttle.c block: Add strong_runtime_opts to BlockDriver 2019-02-25 15:11:27 +01:00
trace-events qcow2: skip writing zero buffers to empty COW areas 2019-05-28 20:30:55 +02:00
vdi.c vdi: Replace bdrv_{read,write}() with bdrv_{pread,pwrite}() 2019-05-10 16:45:40 +02:00
vhdx-endian.c block/vhdx: Don't take address of fields in packed structs 2018-11-05 15:09:54 +01:00
vhdx-log.c block/vhdx: Use IEC binary prefixes for size constants 2019-04-30 15:29:00 +02:00
vhdx.c block/vhdx: Use IEC binary prefixes for size constants 2019-04-30 15:29:00 +02:00
vhdx.h block/vhdx: Use IEC binary prefixes for size constants 2019-04-30 15:29:00 +02:00
vmdk.c vmdk: Set vmdk parent backing_format to vmdk 2019-04-30 15:29:00 +02:00
vpc.c vpc: unlock Coroutine lock to make IO submit Concurrently 2019-04-30 15:29:00 +02:00
vvfat.c vvfat: Replace bdrv_{read,write}() with bdrv_{pread,pwrite}() 2019-05-10 16:45:40 +02:00
vxhs.c block: Add strong_runtime_opts to BlockDriver 2019-02-25 15:11:27 +01:00
win32-aio.c file-win32: Switch to byte-based callbacks 2018-05-15 16:11:41 +02:00
write-threshold.c qapi: Drop qapi_event_send_FOO()'s Error ** argument 2018-08-28 18:21:38 +02:00