zstd significantly reduces cluster compression time.
It provides better compression performance maintaining
the same level of the compression ratio in comparison with
zlib, which, at the moment, is the only compression
method available.
The performance test results:
Test compresses and decompresses qemu qcow2 image with just
installed rhel-7.6 guest.
Image cluster size: 64K. Image on disk size: 2.2G
The test was conducted with brd disk to reduce the influence
of disk subsystem to the test results.
The results is given in seconds.
compress cmd:
time ./qemu-img convert -O qcow2 -c -o compression_type=[zlib|zstd]
src.img [zlib|zstd]_compressed.img
decompress cmd
time ./qemu-img convert -O qcow2
[zlib|zstd]_compressed.img uncompressed.img
compression decompression
zlib zstd zlib zstd
------------------------------------------------------------
real 65.5 16.3 (-75 %) 1.9 1.6 (-16 %)
user 65.0 15.8 5.3 2.5
sys 3.3 0.2 2.0 2.0
Both ZLIB and ZSTD gave the same compression ratio: 1.57
compressed image size in both cases: 1.4G
Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
QAPI part:
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200507082521.29210-4-dplotnikov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The patch enables processing the image compression type defined
for the image and chooses an appropriate method for image clusters
(de)compression.
Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200507082521.29210-3-dplotnikov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
On success path we return what inflate() returns instead of 0. And it
most probably works for Z_STREAM_END as it is positive, but is
definitely broken for Z_BUF_ERROR.
While being here, switch to errno return code, to be closer to
qcow2_compress API (and usual expectations).
Revert condition in if to be more positive. Drop dead initialization of
ret.
Cc: qemu-stable@nongnu.org # v4.0
Fixes: 341926ab83
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200302150930.16218-1-vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
I/O requests to encrypted media should be aligned to the sector size
used by the underlying encryption method, not to BDRV_SECTOR_SIZE.
Fortunately this doesn't break anything at the moment because
both existing QCRYPTO_BLOCK_*_SECTOR_SIZE have the same value as
BDRV_SECTOR_SIZE.
The checks in qcow2_co_preadv_encrypted() are also unnecessary because
they are repeated immediately afterwards in qcow2_co_encdec().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20200213171646.15876-1-berto@igalia.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* Change the qcow2_co_{encrypt|decrypt} to just receive full host and
guest offsets and use this function directly instead of calling
do_perform_cow_encrypt (which is removed by that patch).
* Adjust qcow2_co_encdec to take full host and guest offsets as well.
* Document the qcow2_co_{encrypt|decrypt} arguments
to prevent the bug fixed in former commit from hopefully
happening again.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20190915203655.21638-3-mlevitsk@redhat.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[mreitz: Let perform_cow() return the error value returned by
qcow2_co_encrypt(), as proposed by Vladimir]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Do encryption/decryption in threads, like it is already done for
compression. This improves asynchronous encrypted io.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-9-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Move generic part out of qcow2_co_do_compress, to reuse it for
encryption and rename things that would be shared with encryption path.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Drop dependence on AioContext lock.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-5-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Use thread_pool_submit_co, instead of reinventing it here. Note, that
thread_pool_submit_aio() never returns NULL, so checking it was an
extra thing.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Move compression-on-threads to separate file. Encryption will be in it
too.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Denis Plotnikov