Sphinx's LaTeX builder fails when converting the nested ASCII tables in
f2fs.rst, producing the following error:
"Markup is unsupported in LaTeX: longtable does not support nesting a table."
Wrap the affected ASCII tables in literal code blocks to force Sphinx to
render them verbatim. This prevents nested longtables and fixes the PDF
build failure on Sphinx 8.2.x.
Acked-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Masaharu Noguchi <nogunix@gmail.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
"What is F2FS" is rather a mistitle for the whole f2fs docs, as it
implies the overview section (before "Background and design issues"
section) and the docs covers beyond that: from mount options to
filesystem implementation details.
Retitle and add explicit overview section.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Indent description text so that compression_mode numbered list gets
rendered as such in htmldocs output.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Write hint policy table has two rows which act as section rows: buffered
io and direct io, yet these rows are written as normal rows instead.
Column-span them.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Format compression_algorithm subtable as reST table as it does the
semantic job rather than normal paragraph.
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
errors=%s subtable is shown in htmldocs output as long-running paragraph
instead due to missing separator from its previous paragraph. Add it.
Fixes: b62e71be21 ("f2fs: support errors=remount-ro|continue|panic mountoption")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch allows privileged users to reserve nodes via the
'reserve_node' mount option, which is similar to the existing
'reserve_root' option.
"-o reserve_node=<N>" means <N> nodes are reserved for privileged
users only.
Signed-off-by: Chunhai Guo <guochunhai@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For casefolded directories, f2fs may fall back to a linear search if
a hash-based lookup fails. This can cause severe performance
regressions.
While this behavior can be controlled by userspace tools (e.g. mkfs,
fsck) by setting an on-disk flag, a kernel-level solution is needed
to guarantee the lookup behavior regardless of the on-disk state.
This commit introduces the 'lookup_mode' mount option to provide this
kernel-side control.
The option accepts three values:
- perf: (Default) Enforces a hash-only lookup. The linear fallback
is always disabled.
- compat: Enables the linear search fallback for compatibility with
directory entries from older kernels.
- auto: Determines the mode based on the on-disk flag, preserving the
userspace-based behavior.
Signed-off-by: Daniel Lee <chullee@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs updates from Jaegeuk Kim:
"Three main updates: folio conversion by Matthew, switch to a new mount
API by Hongbo and Eric, and several sysfs entries to tune GCs for ZUFS
with finer granularity by Daeho.
There are also patches to address bugs and issues in the existing
features such as GCs, file pinning, write-while-dio-read, contingous
block allocation, and memory access violations.
Enhancements:
- switch to new mount API and folio conversion
- add sysfs nodes to controle F2FS GCs for ZUFS
- improve performance on the nat entry cache
- drop inode from the donation list when the last file is closed
- avoid splitting bio when reading multiple pages
Bug fixes:
- fix to trigger foreground gc during f2fs_map_blocks() in lfs mode
- make sure zoned device GC to use FG_GC in shortage of free section
- fix to calculate dirty data during has_not_enough_free_secs()
- fix to update upper_p in __get_secs_required() correctly
- wait for inflight dio completion, excluding pinned files read using dio
- don't break allocation when crossing contiguous sections
- vm_unmap_ram() may be called from an invalid context
- fix to avoid out-of-boundary access in dnode page
- fix to avoid panic in f2fs_evict_inode
- fix to avoid UAF in f2fs_sync_inode_meta()
- fix to use f2fs_is_valid_blkaddr_raw() in do_write_page()
- fix UAF of f2fs_inode_info in f2fs_free_dic
- fix to avoid invalid wait context issue
- fix bio memleak when committing super block
- handle nat.blkaddr corruption in f2fs_get_node_info()
In addition, there are also clean-ups and minor bug fixes"
* tag 'f2fs-for-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (109 commits)
f2fs: drop inode from the donation list when the last file is closed
f2fs: add gc_boost_gc_greedy sysfs node
f2fs: add gc_boost_gc_multiple sysfs node
f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode
f2fs: fix to calculate dirty data during has_not_enough_free_secs()
f2fs: fix to update upper_p in __get_secs_required() correctly
f2fs: directly add newly allocated pre-dirty nat entry to dirty set list
f2fs: avoid redundant clean nat entry move in lru list
f2fs: zone: wait for inflight dio completion, excluding pinned files read using dio
f2fs: ignore valid ratio when free section count is low
f2fs: don't break allocation when crossing contiguous sections
f2fs: remove unnecessary tracepoint enabled check
f2fs: merge the two conditions to avoid code duplication
f2fs: vm_unmap_ram() may be called from an invalid context
f2fs: fix to avoid out-of-boundary access in dnode page
f2fs: switch to the new mount api
f2fs: introduce fs_context_operation structure
f2fs: separate the options parsing and options checking
f2fs: Add f2fs_fs_context to record the mount options
f2fs: Allow sbi to be NULL in f2fs_printk
...
We should use "{usr,grp,prj}jquota=" to disable journaled quota,
rather than using off{usr,grp,prj}jquota.
Fixes: 4b2414d04e ("f2fs: support journalled quota")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes two minor typos in Documentation/filesystems/f2fs.rst:
- "ramdom" → "random"
- "reenable" → "re-enable"
The changes improve spelling and consistency in the documentation.
These issues were identified using the 'codespell' tool with the
following command:
$ find Documentation/ -path Documentation/translations -prune -o \
-name '*.rst' -print | xargs codespell
Signed-off-by: Yuanye Ma <yuanye.ma20@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250618225546.104949-1-yuanye.ma20@gmail.com
Introduce a new fault type FAULT_VMALLOC to simulate no memory error in
f2fs_vmalloc().
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
FAULT_KMALLOC 0x000000001
There is one redundant '0' in 32-bits hexademical number of fault type,
remove it.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Support to inject a timeout fault into function, currently it only
support to inject timeout to commit_atomic_write flow to reproduce
inconsistent bug, like the bug fixed by commit f098aeba04 ("f2fs:
fix to avoid atomicity corruption of atomic file").
By default, the new type fault will inject 1000ms timeout, and the
timeout process can be interrupted by SIGKILL.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Introduce a new mount option "nat_bits" to control nat_bits feature,
by default nat_bits feature is disabled.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
F2FS should understand how the device aliasing file works and support
deleting the file after use. A device aliasing file can be created by
mkfs.f2fs tool and it can map the whole device with an extent, not
using node blocks. The file space should be pinned and normally used for
read-only usages.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This reverts commit 930e260763 ("f2fs: remove obsolete whint_mode"), as we
decide to pass write hints to the disk.
Cc: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Use it to simulate no free segment case during block allocation.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We will encounter below inconsistent status when FAULT_BLKADDR type
fault injection is on.
Info: checkpoint state = d6 : nat_bits crc fsck compacted_summary orphan_inodes sudden-power-off
[ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1c100 has i_blocks: 000000c0, but has 191 blocks
[FIX] (fsck_chk_inode_blk:1260) --> [0x1c100] i_blocks=0x000000c0 -> 0xbf
[FIX] (fsck_chk_inode_blk:1269) --> [0x1c100] i_compr_blocks=0x00000026 -> 0x27
[ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1cadb has i_blocks: 0000002f, but has 46 blocks
[FIX] (fsck_chk_inode_blk:1260) --> [0x1cadb] i_blocks=0x0000002f -> 0x2e
[FIX] (fsck_chk_inode_blk:1269) --> [0x1cadb] i_compr_blocks=0x00000011 -> 0x12
[ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1c62c has i_blocks: 00000002, but has 1 blocks
[FIX] (fsck_chk_inode_blk:1260) --> [0x1c62c] i_blocks=0x00000002 -> 0x1
After we inject fault into f2fs_is_valid_blkaddr() during truncation,
a) it missed to increase @nr_free or @valid_blocks
b) it can cause in blkaddr leak in truncated dnode
Which may cause inconsistent status.
This patch separates FAULT_BLKADDR_CONSISTENCE from FAULT_BLKADDR,
and rename FAULT_BLKADDR to FAULT_BLKADDR_VALIDITY
so that we can:
a) use FAULT_BLKADDR_CONSISTENCE in f2fs_truncate_data_blocks_range()
to simulate inconsistent issue independently, then it can verify fsck
repair flow.
b) FAULT_BLKADDR_VALIDITY fault will not cause any inconsistent status,
we can just use it to check error path handling in kernel side.
Reviewed-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch supports errors=remount-ro|continue|panic mount option
for f2fs.
f2fs behaves as below in three different modes:
mode continue remount-ro panic
access ops normal noraml N/A
syscall errors -EIO -EROFS N/A
mount option rw ro N/A
pending dir write keep keep N/A
pending non-dir write drop keep N/A
pending node write drop keep N/A
pending meta write keep keep N/A
By default it uses "continue" mode.
[Yangtao helps to clean up function's name]
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There is a problem with the html converted from the previous
commit 6047de5482 ("f2fs: add barrier mount option")
code submission. Probably something like this:
barrier If this option is set, cache_flush commands are allowed to be
Let's fix it.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a runtime hot/cold data separation method
for f2fs, in order to improve the accuracy for data temperature
classification, reduce the garbage collection overhead after
long-term data updates.
Enhanced hot/cold data separation can record data block update
frequency as "age" of the extent per inode, and take use of the age
info to indicate better temperature type for data block allocation:
- It records total data blocks allocated since mount;
- When file extent has been updated, it calculate the count of data
blocks allocated since last update as the age of the extent;
- Before the data block allocated, it searches for the age info and
chooses the suitable segment for allocation.
Test and result:
- Prepare: create about 30000 files
* 3% for cold files (with cold file extension like .apk, from 3M to 10M)
* 50% for warm files (with random file extension like .FcDxq, from 1K
to 4M)
* 47% for hot files (with hot file extension like .db, from 1K to 256K)
- create(5%)/random update(90%)/delete(5%) the files
* total write amount is about 70G
* fsync will be called for .db files, and buffered write will be used
for other files
The storage of test device is large enough(128G) so that it will not
switch to SSR mode during the test.
Benefit: dirty segment count increment reduce about 14%
- before: Dirty +21110
- after: Dirty +18286
Signed-off-by: qixiaoyu1 <qixiaoyu1@xiaomi.com>
Signed-off-by: xiongping1 <xiongping1@xiaomi.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As f2fs component in bugzilla.kernel.org was created and used since
2018-7.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds a mount option, barrier, in f2fs.
The barrier option is the opposite of nobarrier.
If this option is set, cache_flush commands are allowed to be issued.
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch supports to inject fault into f2fs_is_valid_blkaddr() to
simulate accessing inconsistent data/meta block addressses from caller.
Usage:
a) echo 262144 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=262144 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we mainly fixed some corner cases that manipulate a
per-file compression flag inappropriately. And, we found f2fs counted
valid blocks in a section incorrectly when zone capacity is set, and
thus, fixed it with additional sysfs entry to check it easily.
Lastly, this series includes several patches with respect to the new
atomic write support such as a couple of bug fixes and re-adding
atomic_write_abort support that we removed by mistake in the previous
release.
Enhancements:
- add sysfs entries to understand atomic write operations and zone
capacity
- introduce memory mode to get a hint for low-memory devices
- adjust the waiting time of foreground GC
- decompress clusters under softirq to avoid non-deterministic
latency
- do not skip updating inode when retrying to flush node page
- enforce single zone capacity
Bug fixes:
- set the compression/no-compression flags correctly
- revive F2FS_IOC_ABORT_VOLATILE_WRITE
- check inline_data during compressed inode conversion
- understand zone capacity when calculating valid block count
As usual, the series includes several minor clean-ups and sanity
checks"
* tag 'f2fs-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
f2fs: use onstack pages instead of pvec
f2fs: intorduce f2fs_all_cluster_page_ready
f2fs: clean up f2fs_abort_atomic_write()
f2fs: handle decompress only post processing in softirq
f2fs: do not allow to decompress files have FI_COMPRESS_RELEASED
f2fs: do not set compression bit if kernel doesn't support
f2fs: remove device type check for direct IO
f2fs: fix null-ptr-deref in f2fs_get_dnode_of_data
f2fs: revive F2FS_IOC_ABORT_VOLATILE_WRITE
f2fs: fix to do sanity check on segment type in build_sit_entries()
f2fs: obsolete unused MAX_DISCARD_BLOCKS
f2fs: fix to avoid use f2fs_bug_on() in f2fs_new_node_page()
f2fs: fix to remove F2FS_COMPR_FL and tag F2FS_NOCOMP_FL at the same time
f2fs: introduce sysfs atomic write statistics
f2fs: don't bother wait_ms by foreground gc
f2fs: invalidate meta pages only for post_read required inode
f2fs: allow compression of files without blocks
f2fs: fix to check inline_data during compressed inode conversion
f2fs: Delete f2fs_copy_page() and replace with memcpy_page()
f2fs: fix to invalidate META_MAPPING before DIO write
...
Introduce memory mode to supports "normal" and "low" memory modes.
"low" mode is to support low memory devices. Because of the nature of
low memory devices, in this mode, f2fs will try to save memory sometimes
by sacrificing performance. "normal" mode is the default mode and same
as before.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since commit c61404153e ("f2fs: introduce FI_COMPRESS_RELEASED
instead of using IMMUTABLE bit"), we no longer use the IMMUTABLE
bit to prevent writing data for compression. Let's correct the
corresponding documentation.
BTW, this patch fixes some alignment issues in the compress
metadata layout.
Signed-off-by: Chao Liu <liuchao@coolpad.com>
Link: https://lore.kernel.org/r/20220613020800.3379482-1-chaoliu719@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
f2fs: support fault injection for f2fs_trylock_op()
This patch supports to inject fault into f2fs_trylock_op().
Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we've applied relatively small number of patches which
fix subtle corner cases mainly, while introducing a new mount option
to be able to fragment the disk intentionally for performance tests.
Enhancements:
- add a mount option to fragmente on-disk layout to understand the
performance
- support direct IO for multi-partitions
- add a fault injection of dquot_initialize
Bug fixes:
- address some lockdep complaints
- fix a deadlock issue with quota
- fix a memory tuning condition
- fix compression condition to improve the ratio
- fix disabling compression on the non-empty compressed file
- invalidate cached pages before IPU/DIO writes
And, we've added some minor clean-ups as usual"
* tag 'f2fs-for-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: fix UAF in f2fs_available_free_memory
f2fs: invalidate META_MAPPING before IPU/DIO write
f2fs: support fault injection for dquot_initialize()
f2fs: fix incorrect return value in f2fs_sanity_check_ckpt()
f2fs: compress: disallow disabling compress on non-empty compressed file
f2fs: compress: fix overwrite may reduce compress ratio unproperly
f2fs: multidevice: support direct IO
f2fs: introduce fragment allocation mode mount option
f2fs: replace snprintf in show functions with sysfs_emit
f2fs: include non-compressed blocks in compr_written_block
f2fs: fix wrong condition to trigger background checkpoint correctly
f2fs: fix to use WHINT_MODE
f2fs: fix up f2fs_lookup tracepoints
f2fs: set SBI_NEED_FSCK flag when inconsistent node block found
f2fs: introduce excess_dirty_threshold()
f2fs: avoid attaching SB_ACTIVE flag during mount
f2fs: quota: fix potential deadlock
f2fs: should use GFP_NOFS for directory inodes
This patch adds a new function f2fs_dquot_initialize() to wrap
dquot_initialize(), and it supports to inject fault into
f2fs_dquot_initialize() to simulate inner failure occurs in
dquot_initialize().
Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added two options into "mode=" mount option to make it possible for
developers to simulate filesystem fragmentation/after-GC situation
itself. The developers use these modes to understand filesystem
fragmentation/after-GC condition well, and eventually get some
insights to handle them better.
"fragment:segment": f2fs allocates a new segment in ramdom position.
With this, we can simulate the after-GC condition.
"fragment:block" : We can scatter block allocation with
"max_fragment_chunk" and "max_fragment_hole" sysfs
nodes. f2fs will allocate 1..<max_fragment_chunk>
blocks in a chunk and make a hole in the length of
1..<max_fragment_hole> by turns in a newly allocated
free segment. Plus, this mode implicitly enables
"fragment:segment" option for more randomness.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The value of FAULT_* macros and its description in f2fs.rst became
inconsistent, fix this to keep compatibility of fault injection
interface.
Fixes: 67883ade7a ("f2fs: remove FAULT_ALLOC_BIO")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch supports to inject fault into f2fs_kmem_cache_alloc().
Usage:
a) echo 32768 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=32768 <dev> <mountpoint>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For compressed file, after release compress blocks, don't allow write
direct, but we should allow write direct after truncate to zero.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As James Z reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=213877
[1.] One-line summary of the problem:
Mount multiple SMR block devices exceed certain number cause system non-response
[2.] Full description of the problem/report:
Created some F2FS on SMR devices (mkfs.f2fs -m), then mounted in sequence. Each device is the same Model: HGST HSH721414AL (Size 14TB).
Empirically, found that when the amount of SMR device * 1.5Gb > System RAM, the system ran out of memory and hung. No dmesg output. For example, 24 SMR Disk need 24*1.5GB = 36GB. A system with 32G RAM can only mount 21 devices, the 22nd device will be a reproducible cause of system hang.
The number of SMR devices with other FS mounted on this system does not interfere with the result above.
[3.] Keywords (i.e., modules, networking, kernel):
F2FS, SMR, Memory
[4.] Kernel information
[4.1.] Kernel version (uname -a):
Linux 5.13.4-200.fc34.x86_64 #1 SMP Tue Jul 20 20:27:29 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
[4.2.] Kernel .config file:
Default Fedora 34 with f2fs-tools-1.14.0-2.fc34.x86_64
[5.] Most recent kernel version which did not have the bug:
None
[6.] Output of Oops.. message (if applicable) with symbolic information
resolved (see Documentation/admin-guide/oops-tracing.rst)
None
[7.] A small shell script or example program which triggers the
problem (if possible)
mount /dev/sdX /mnt/0X
[8.] Memory consumption
With 24 * 14T SMR Block device with F2FS
free -g
total used free shared buff/cache available
Mem: 46 36 0 0 10 10
Swap: 0 0 0
With 3 * 14T SMR Block device with F2FS
free -g
total used free shared buff/cache available
Mem: 7 5 0 0 1 1
Swap: 7 0 7
The root cause is, there are three bitmaps:
- cur_valid_map
- ckpt_valid_map
- discard_map
and each of them will cost ~500MB memory, {cur, ckpt}_valid_map are
necessary, but discard_map is optional, since this bitmap will only be
useful in mountpoint that small discard is enabled.
For a blkzoned device such as SMR or ZNS devices, f2fs will only issue
discard for a section(zone) when all blocks of that section are invalid,
so, for such device, we don't need small discard functionality at all.
This patch introduces a new mountoption "discard_unit=block|segment|
section" to support issuing discard with different basic unit which is
aligned to block, segment or section, so that user can specify
"discard_unit=segment" or "discard_unit=section" to disable small
discard functionality.
Note that this mount option can not be changed by remount() due to
related metadata need to be initialized during mount().
In order to save memory, let's use "discard_unit=section" for blkzoned
device by default.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When we create a directory with enable compression, all file write into
directory will try to compress.But sometimes we may know, new file
cannot meet compression ratio requirements.
We need a nocompress extension to skip those files to avoid unnecessary
compress page test.
After add nocompress_extension, the priority should be:
dir_flag < comp_extention,nocompress_extension < comp_file_flag,
no_comp_file_flag.
Priority in between FS_COMPR_FL, FS_NOCOMP_FS, extensions:
* compress_extension=so; nocompress_extension=zip; chattr +c dir;
touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
and baz.txt should be compresse, bar.zip should be non-compressed.
chattr +c dir/bar.zip can enable compress on bar.zip.
* compress_extension=so; nocompress_extension=zip; chattr -c dir;
touch dir/foo.so; touch dir/bar.zip; touch dir/baz.txt; then foo.so
should be compresse, bar.zip and baz.txt should be non-compressed.
chattr+c dir/bar.zip; chattr+c dir/baz.txt; can enable compress on
bar.zip and baz.txt.
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise whole section after tab will be invisible in compiled
html format document.
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Fixes: 89272ca110 ("docs: filesystems: convert f2fs.txt to ReST")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
User or developer may still be confused about why f2fs doesn't expose
compressed space to userspace, add description about compressed space
handling policy into f2fs documentation.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this patch, we will add two new mount options: "gc_merge" and
"nogc_merge", when background_gc is on, "gc_merge" option can be
set to let background GC thread to handle foreground GC requests,
it can eliminate the sluggish issue caused by slow foreground GC
operation when GC is triggered from a process with limited I/O
and CPU resources.
Original idea is from Xiang.
Signed-off-by: Gao Xiang <xiang@kernel.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
