Add zstd compression and decompression support to BtrFS. zstd at its
fastest level compresses almost as well as zlib, while offering much
faster compression and decompression, approaching lzo speeds.
I benchmarked btrfs with zstd compression against no compression, lzo
compression, and zlib compression. I benchmarked two scenarios. Copying
a set of files to btrfs, and then reading the files. Copying a tarball
to btrfs, extracting it to btrfs, and then reading the extracted files.
After every operation, I call `sync` and include the sync time.
Between every pair of operations I unmount and remount the filesystem
to avoid caching. The benchmark files can be found in the upstream
zstd source repository under
`contrib/linux-kernel/{btrfs-benchmark.sh,btrfs-extract-benchmark.sh}`
[1] [2].
I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM.
The VM is running on a MacBook Pro with a 3.1 GHz Intel Core i7 processor,
16 GB of RAM, and a SSD.
The first compression benchmark is copying 10 copies of the unzipped
Silesia corpus [3] into a BtrFS filesystem mounted with
`-o compress-force=Method`. The decompression benchmark times how long
it takes to `tar` all 10 copies into `/dev/null`. The compression ratio is
measured by comparing the output of `df` and `du`. See the benchmark file
[1] for details. I benchmarked multiple zstd compression levels, although
the patch uses zstd level 1.
| Method | Ratio | Compression MB/s | Decompression speed |
|---------|-------|------------------|---------------------|
| None | 0.99 | 504 | 686 |
| lzo | 1.66 | 398 | 442 |
| zlib | 2.58 | 65 | 241 |
| zstd 1 | 2.57 | 260 | 383 |
| zstd 3 | 2.71 | 174 | 408 |
| zstd 6 | 2.87 | 70 | 398 |
| zstd 9 | 2.92 | 43 | 406 |
| zstd 12 | 2.93 | 21 | 408 |
| zstd 15 | 3.01 | 11 | 354 |
The next benchmark first copies `linux-4.11.6.tar` [4] to btrfs. Then it
measures the compression ratio, extracts the tar, and deletes the tar.
Then it measures the compression ratio again, and `tar`s the extracted
files into `/dev/null`. See the benchmark file [2] for details.
| Method | Tar Ratio | Extract Ratio | Copy (s) | Extract (s)| Read (s) |
|--------|-----------|---------------|----------|------------|----------|
| None | 0.97 | 0.78 | 0.981 | 5.501 | 8.807 |
| lzo | 2.06 | 1.38 | 1.631 | 8.458 | 8.585 |
| zlib | 3.40 | 1.86 | 7.750 | 21.544 | 11.744 |
| zstd 1 | 3.57 | 1.85 | 2.579 | 11.479 | 9.389 |
[1] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-benchmark.sh
[2] https://github.com/facebook/zstd/blob/dev/contrib/linux-kernel/btrfs-extract-benchmark.sh
[3] http://sun.aei.polsl.pl/~sdeor/index.php?page=silesia
[4] https://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.11.6.tar.xz
zstd source repository: https://github.com/facebook/zstd
Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
A programmer who is trying to implement calling the btrfs SEARCH
or SEARCH_V2 ioctl will probably soon end up reading this struct
definition.
Properly document the input fields to prevent common misconceptions:
1. The search space is linear, not 3 dimensional. The invidual min/max
values for objectid, type and offset cannot be used to filter the
result, they only define the endpoints of an interval.
2. The transaction id (a.k.a. generation) filter applies only on
transaction id of the last COW operation on a whole metadata page, not
on individual items.
Ad 1. The first misunderstanding was helped by the previous misleading
comments on min/max type and offset:
"keys returned will be >= min and <= max".
Ad 2. For example, running btrfs balance will happily cause rewriting of
metadata pages that contain a filesystem tree of a read only subvolume,
causing transids to be increased.
Also, improve descriptions of tree_id and nr_items and add in/out
annotations.
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_balance_args are only used for the balance ioctl, so use __u
instead of __le here for consistency. The __le usage was introduced in
bc3094673f and dee32d0ac3 and was probably a result of
copy/pasting when the code was written.
The usage of __le did not break anything, but it's unnecessary. Also,
this change makes the code less confusing for the careful reader.
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_err_str function is not called from anywhere and is replicated
in the userspace headers for btrfs-progs.
It's removal also fixes the following linux/btrfs.h userspace
compilation error:
/usr/include/linux/btrfs.h: In function 'btrfs_err_str':
/usr/include/linux/btrfs.h:740:11: error: 'NULL' undeclared (first use in this function)
return NULL;
Suggested-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are two separate issues that can lead to corrupted free space
trees.
1. The free space tree bitmaps had an endianness issue on big-endian
systems which is fixed by an earlier patch in this series.
2. btrfs-progs before v4.7.3 modified filesystems without updating the
free space tree.
To catch both of these issues at once, we need to force the free space
tree to be rebuilt. To do so, add a FREE_SPACE_TREE_VALID compat_ro bit.
If the bit isn't set, we know that it was either produced by a broken
big-endian kernel or may have been corrupted by btrfs-progs.
This also provides us with a way to add rudimentary read-write support
for the free space tree to btrfs-progs: it can just clear this bit and
have the kernel rebuild the free space tree.
Cc: stable@vger.kernel.org # 4.5+
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
BTRFS_IOC_LOGICAL_INO takes a btrfs_ioctl_logical_ino_args as argument,
not a btrfs_ioctl_ino_path_args. The lines were probably copy/pasted
when the code was written.
Since btrfs_ioctl_logical_ino_args and btrfs_ioctl_ino_path_args have
the same size, the actual IOCTL definition here does not change.
But, it makes the code less confusing for the reader.
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch fixes this build error.
/usr/include/linux/btrfs.h:121:3: error: unknown type name ‘u64’
u64 devid;
^~~
Fixes: 6b526ed70c ("btrfs: introduce device delete by devid")
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Signed-off-by: David Sterba <dsterba@suse.com>
struct btrfs_ioctl_defrag_range_args is used by the BTRFS_IOC_DEFRAG_RANGE
ioctl.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The BTRFS_BALANCE_* flags are used by struct btrfs_ioctl_balance_args.flags
and btrfs_ioctl_balance_args.{data,meta,sys}.flags in the BTRFS_IOC_BALANCE
ioctl.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The compat/compat_ro/incompat feature flags are used by the feature set/get
ioctls.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The BTRFS_QGROUP_LIMIT_* flags are required to tell the kernel which
fields are valid when using the BTRFS_IOC_QGROUP_LIMIT ioctl.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
BTRFS_LABEL_SIZE is required to define the BTRFS_IOC_GET_FSLABEL and
BTRFS_IOC_SET_FSLABEL ioctls.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename BTRFS_DEVICE_BY_ID so it's more descriptive that we specify the
device by id, it'll be part of the public API. The mask of supported
flags is also renamed, only for internal use.
The error code for unknown flags is EOPNOTSUPP, fixed.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This introduces new ioctl BTRFS_IOC_RM_DEV_V2, which uses enhanced struct
btrfs_ioctl_vol_args_v2 to carry devid as an user argument.
The patch won't delete the old ioctl interface and so kernel remains
backward compatible with user land progs.
Test case/script:
echo "0 $(blockdev --getsz /dev/sdf) linear /dev/sdf 0" | dmsetup create bad_disk
mkfs.btrfs -f -d raid1 -m raid1 /dev/sdd /dev/sde /dev/mapper/bad_disk
mount /dev/sdd /btrfs
dmsetup suspend bad_disk
echo "0 $(blockdev --getsz /dev/sdf) error /dev/sdf 0" | dmsetup load bad_disk
dmsetup resume bad_disk
echo "bad disk failed. now deleting/replacing"
btrfs dev del 3 /btrfs
echo $?
btrfs fi show /btrfs
umount /btrfs
btrfs-show-super /dev/sdd | egrep num_device
dmsetup remove bad_disk
wipefs -a /dev/sdf
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reported-by: Martin <m_btrfs@ml1.co.uk>
[ adjust messages, s/disk/device/ ]
Signed-off-by: David Sterba <dsterba@suse.com>
Similar to the 'limit' filter, we can enhance the 'usage' filter to
accept a range. The change is backward compatible, the range is applied
only in connection with the BTRFS_BALANCE_ARGS_USAGE_RANGE flag.
We don't have a usecase yet, the current syntax has been sufficient. The
enhancement should provide parity with other range-like filters.
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Balance block groups which have the given number of stripes, defined by
a range min..max. This is useful to selectively rebalance only chunks
that do not span enough devices, applies to RAID0/10/5/6.
Signed-off-by: Gabríel Arthúr Pétursson <gabriel@system.is>
[ renamed bargs members, added to the UAPI, wrote the changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
The 'limit' filter is underdesigned, it should have been a range for
[min,max], with some relaxed semantics when one of the bounds is
missing. Besides that, using a full u64 for a single value is a waste of
bytes.
Let's fix both by extending the use of the u64 bytes for the [min,max]
range. This can be done in a backward compatible way, the range will be
interpreted only if the appropriate flag is set
(BTRFS_BALANCE_ARGS_LIMIT_RANGE).
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
device replace could fail due to another running scrub process or any
other errors btrfs_scrub_dev() may hit, but this failure doesn't get
returned to userspace.
The following steps could reproduce this issue
mkfs -t btrfs -f /dev/sdb1 /dev/sdb2
mount /dev/sdb1 /mnt/btrfs
while true; do btrfs scrub start -B /mnt/btrfs >/dev/null 2>&1; done &
btrfs replace start -Bf /dev/sdb2 /dev/sdb3 /mnt/btrfs
# if this replace succeeded, do the following and repeat until
# you see this log in dmesg
# BTRFS: btrfs_scrub_dev(/dev/sdb2, 2, /dev/sdb3) failed -115
#btrfs replace start -Bf /dev/sdb3 /dev/sdb2 /mnt/btrfs
# once you see the error log in dmesg, check return value of
# replace
echo $?
Introduce a new dev replace result
BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS
to catch -EINPROGRESS explicitly and return other errors directly to
userspace.
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Creating sprout will change the fsid of the mounted root.
do the same on the sysfs as well.
reproducer:
mount /dev/sdb /btrfs (seed disk)
btrfs dev add /dev/sdc /btrfs
mount -o rw,remount /btrfs
btrfs dev del /dev/sdb /btrfs
mount /dev/sdb /btrfs
Error:
kobject_add_internal failed for fe350492-dc28-4051-a601-e017b17e6145 with -EEXIST, don't try to register things with the same name in the same directory.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This new ioctl call allows the user to supply a buffer of varying size in which
a tree search can store its results. This is much more flexible if you want to
receive items which are larger than the current fixed buffer of 3992 bytes or
if you want to fetch more items at once. Items larger than this buffer are for
example some of the type EXTENT_CSUM.
Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
Provide the basic information about filesystem through the ioctl:
* b-tree node size (same as leaf size)
* sector size
* expected alignment of CLONE_RANGE and EXTENT_SAME ioctl arguments
Backward compatibility: if the values are 0, kernel does not provide
this information, the applications should ignore them.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
This started as debugging helper, to watch the effects of converting
between raid levels on multiple devices, but could be useful standalone.
In my case the usage filter was not finegrained enough and led to
converting too many chunks at once. Another example use is in connection
with drange+devid or vrange filters that allow to work with a specific
chunk or even with a chunk on a given device.
The limit filter applies last, the value of 0 means no limiting.
CC: Ilya Dryomov <idryomov@gmail.com>
CC: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
