0001 What: /sys/fs/f2fs/<disk>/gc_max_sleep_time
0002 Date: July 2013
0003 Contact: "Namjae Jeon" <namjae.jeon@samsung.com>
0004 Description: Controls the maximum sleep time for gc_thread. Time
0005 is in milliseconds.
0006
0007 What: /sys/fs/f2fs/<disk>/gc_min_sleep_time
0008 Date: July 2013
0009 Contact: "Namjae Jeon" <namjae.jeon@samsung.com>
0010 Description: Controls the minimum sleep time for gc_thread. Time
0011 is in milliseconds.
0012
0013 What: /sys/fs/f2fs/<disk>/gc_no_gc_sleep_time
0014 Date: July 2013
0015 Contact: "Namjae Jeon" <namjae.jeon@samsung.com>
0016 Description: Controls the default sleep time for gc_thread. Time
0017 is in milliseconds.
0018
0019 What: /sys/fs/f2fs/<disk>/gc_idle
0020 Date: July 2013
0021 Contact: "Namjae Jeon" <namjae.jeon@samsung.com>
0022 Description: Controls the victim selection policy for garbage collection.
0023 Setting gc_idle = 0(default) will disable this option. Setting:
0024
0025 =========== ===============================================
0026 gc_idle = 1 will select the Cost Benefit approach & setting
0027 gc_idle = 2 will select the greedy approach & setting
0028 gc_idle = 3 will select the age-threshold based approach.
0029 =========== ===============================================
0030
0031 What: /sys/fs/f2fs/<disk>/reclaim_segments
0032 Date: October 2013
0033 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0034 Description: This parameter controls the number of prefree segments to be
0035 reclaimed. If the number of prefree segments is larger than
0036 the number of segments in the proportion to the percentage
0037 over total volume size, f2fs tries to conduct checkpoint to
0038 reclaim the prefree segments to free segments.
0039 By default, 5% over total # of segments.
0040
0041 What: /sys/fs/f2fs/<disk>/main_blkaddr
0042 Date: November 2019
0043 Contact: "Ramon Pantin" <pantin@google.com>
0044 Description: Shows first block address of MAIN area.
0045
0046 What: /sys/fs/f2fs/<disk>/ipu_policy
0047 Date: November 2013
0048 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0049 Description: Controls the in-place-update policy.
0050 updates in f2fs. User can set:
0051
0052 ==== =================
0053 0x01 F2FS_IPU_FORCE
0054 0x02 F2FS_IPU_SSR
0055 0x04 F2FS_IPU_UTIL
0056 0x08 F2FS_IPU_SSR_UTIL
0057 0x10 F2FS_IPU_FSYNC
0058 0x20 F2FS_IPU_ASYNC
0059 0x40 F2FS_IPU_NOCACHE
0060 0x80 F2FS_IPU_HONOR_OPU_WRITE
0061 ==== =================
0062
0063 Refer segment.h for details.
0064
0065 What: /sys/fs/f2fs/<disk>/min_ipu_util
0066 Date: November 2013
0067 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0068 Description: Controls the FS utilization condition for the in-place-update
0069 policies. It is used by F2FS_IPU_UTIL and F2FS_IPU_SSR_UTIL policies.
0070
0071 What: /sys/fs/f2fs/<disk>/min_fsync_blocks
0072 Date: September 2014
0073 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0074 Description: Controls the dirty page count condition for the in-place-update
0075 policies.
0076
0077 What: /sys/fs/f2fs/<disk>/min_seq_blocks
0078 Date: August 2018
0079 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0080 Description: Controls the dirty page count condition for batched sequential
0081 writes in writepages.
0082
0083 What: /sys/fs/f2fs/<disk>/min_hot_blocks
0084 Date: March 2017
0085 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0086 Description: Controls the dirty page count condition for redefining hot data.
0087
0088 What: /sys/fs/f2fs/<disk>/min_ssr_sections
0089 Date: October 2017
0090 Contact: "Chao Yu" <yuchao0@huawei.com>
0091 Description: Controls the free section threshold to trigger SSR allocation.
0092 If this is large, SSR mode will be enabled early.
0093
0094 What: /sys/fs/f2fs/<disk>/max_small_discards
0095 Date: November 2013
0096 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0097 Description: Controls the issue rate of discard commands that consist of small
0098 blocks less than 2MB. The candidates to be discarded are cached until
0099 checkpoint is triggered, and issued during the checkpoint.
0100 By default, it is disabled with 0.
0101
0102 What: /sys/fs/f2fs/<disk>/max_discard_request
0103 Date: December 2021
0104 Contact: "Konstantin Vyshetsky" <vkon@google.com>
0105 Description: Controls the number of discards a thread will issue at a time.
0106 Higher number will allow the discard thread to finish its work
0107 faster, at the cost of higher latency for incomming I/O.
0108
0109 What: /sys/fs/f2fs/<disk>/min_discard_issue_time
0110 Date: December 2021
0111 Contact: "Konstantin Vyshetsky" <vkon@google.com>
0112 Description: Controls the interval the discard thread will wait between
0113 issuing discard requests when there are discards to be issued and
0114 no I/O aware interruptions occur.
0115
0116 What: /sys/fs/f2fs/<disk>/mid_discard_issue_time
0117 Date: December 2021
0118 Contact: "Konstantin Vyshetsky" <vkon@google.com>
0119 Description: Controls the interval the discard thread will wait between
0120 issuing discard requests when there are discards to be issued and
0121 an I/O aware interruption occurs.
0122
0123 What: /sys/fs/f2fs/<disk>/max_discard_issue_time
0124 Date: December 2021
0125 Contact: "Konstantin Vyshetsky" <vkon@google.com>
0126 Description: Controls the interval the discard thread will wait when there are
0127 no discard operations to be issued.
0128
0129 What: /sys/fs/f2fs/<disk>/discard_granularity
0130 Date: July 2017
0131 Contact: "Chao Yu" <yuchao0@huawei.com>
0132 Description: Controls discard granularity of inner discard thread. Inner thread
0133 will not issue discards with size that is smaller than granularity.
0134 The unit size is one block(4KB), now only support configuring
0135 in range of [1, 512]. Default value is 4(=16KB).
0136
0137 What: /sys/fs/f2fs/<disk>/umount_discard_timeout
0138 Date: January 2019
0139 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0140 Description: Set timeout to issue discard commands during umount.
0141 Default: 5 secs
0142
0143 What: /sys/fs/f2fs/<disk>/pending_discard
0144 Date: November 2021
0145 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0146 Description: Shows the number of pending discard commands in the queue.
0147
0148 What: /sys/fs/f2fs/<disk>/max_victim_search
0149 Date: January 2014
0150 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0151 Description: Controls the number of trials to find a victim segment
0152 when conducting SSR and cleaning operations. The default value
0153 is 4096 which covers 8GB block address range.
0154
0155 What: /sys/fs/f2fs/<disk>/migration_granularity
0156 Date: October 2018
0157 Contact: "Chao Yu" <yuchao0@huawei.com>
0158 Description: Controls migration granularity of garbage collection on large
0159 section, it can let GC move partial segment{s} of one section
0160 in one GC cycle, so that dispersing heavy overhead GC to
0161 multiple lightweight one.
0162
0163 What: /sys/fs/f2fs/<disk>/dir_level
0164 Date: March 2014
0165 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0166 Description: Controls the directory level for large directory. If a
0167 directory has a number of files, it can reduce the file lookup
0168 latency by increasing this dir_level value. Otherwise, it
0169 needs to decrease this value to reduce the space overhead.
0170 The default value is 0.
0171
0172 What: /sys/fs/f2fs/<disk>/ram_thresh
0173 Date: March 2014
0174 Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
0175 Description: Controls the memory footprint used by free nids and cached
0176 nat entries. By default, 1 is set, which indicates
0177 10 MB / 1 GB RAM.
0178
0179 What: /sys/fs/f2fs/<disk>/batched_trim_sections
0180 Date: February 2015
0181 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0182 Description: Controls the trimming rate in batch mode.
0183 <deprecated>
0184
0185 What: /sys/fs/f2fs/<disk>/cp_interval
0186 Date: October 2015
0187 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0188 Description: Controls the checkpoint timing, set to 60 seconds by default.
0189
0190 What: /sys/fs/f2fs/<disk>/idle_interval
0191 Date: January 2016
0192 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0193 Description: Controls the idle timing of system, if there is no FS operation
0194 during given interval.
0195 Set to 5 seconds by default.
0196
0197 What: /sys/fs/f2fs/<disk>/discard_idle_interval
0198 Date: September 2018
0199 Contact: "Chao Yu" <yuchao0@huawei.com>
0200 Contact: "Sahitya Tummala" <stummala@codeaurora.org>
0201 Description: Controls the idle timing of discard thread given
0202 this time interval.
0203 Default is 5 secs.
0204
0205 What: /sys/fs/f2fs/<disk>/gc_idle_interval
0206 Date: September 2018
0207 Contact: "Chao Yu" <yuchao0@huawei.com>
0208 Contact: "Sahitya Tummala" <stummala@codeaurora.org>
0209 Description: Controls the idle timing for gc path. Set to 5 seconds by default.
0210
0211 What: /sys/fs/f2fs/<disk>/iostat_enable
0212 Date: August 2017
0213 Contact: "Chao Yu" <yuchao0@huawei.com>
0214 Description: Controls to enable/disable IO stat.
0215
0216 What: /sys/fs/f2fs/<disk>/ra_nid_pages
0217 Date: October 2015
0218 Contact: "Chao Yu" <chao2.yu@samsung.com>
0219 Description: Controls the count of nid pages to be readaheaded.
0220 When building free nids, F2FS reads NAT blocks ahead for
0221 speed up. Default is 0.
0222
0223 What: /sys/fs/f2fs/<disk>/dirty_nats_ratio
0224 Date: January 2016
0225 Contact: "Chao Yu" <chao2.yu@samsung.com>
0226 Description: Controls dirty nat entries ratio threshold, if current
0227 ratio exceeds configured threshold, checkpoint will
0228 be triggered for flushing dirty nat entries.
0229
0230 What: /sys/fs/f2fs/<disk>/lifetime_write_kbytes
0231 Date: January 2016
0232 Contact: "Shuoran Liu" <liushuoran@huawei.com>
0233 Description: Shows total written kbytes issued to disk.
0234
0235 What: /sys/fs/f2fs/<disk>/features
0236 Date: July 2017
0237 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0238 Description: <deprecated: should use /sys/fs/f2fs/<disk>/feature_list/
0239 Shows all enabled features in current device.
0240 Supported features:
0241 encryption, blkzoned, extra_attr, projquota, inode_checksum,
0242 flexible_inline_xattr, quota_ino, inode_crtime, lost_found,
0243 verity, sb_checksum, casefold, readonly, compression, pin_file.
0244
0245 What: /sys/fs/f2fs/<disk>/feature_list/
0246 Date: June 2021
0247 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0248 Description: Expand /sys/fs/f2fs/<disk>/features to meet sysfs rule.
0249 Supported on-disk features:
0250 encryption, block_zoned (aka blkzoned), extra_attr,
0251 project_quota (aka projquota), inode_checksum,
0252 flexible_inline_xattr, quota_ino, inode_crtime, lost_found,
0253 verity, sb_checksum, casefold, readonly, compression.
0254 Note that, pin_file is moved into /sys/fs/f2fs/features/.
0255
0256 What: /sys/fs/f2fs/features/
0257 Date: July 2017
0258 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0259 Description: Shows all enabled kernel features.
0260 Supported features:
0261 encryption, block_zoned, extra_attr, project_quota,
0262 inode_checksum, flexible_inline_xattr, quota_ino,
0263 inode_crtime, lost_found, verity, sb_checksum,
0264 casefold, readonly, compression, test_dummy_encryption_v2,
0265 atomic_write, pin_file, encrypted_casefold.
0266
0267 What: /sys/fs/f2fs/<disk>/inject_rate
0268 Date: May 2016
0269 Contact: "Sheng Yong" <shengyong1@huawei.com>
0270 Description: Controls the injection rate of arbitrary faults.
0271
0272 What: /sys/fs/f2fs/<disk>/inject_type
0273 Date: May 2016
0274 Contact: "Sheng Yong" <shengyong1@huawei.com>
0275 Description: Controls the injection type of arbitrary faults.
0276
0277 What: /sys/fs/f2fs/<disk>/dirty_segments
0278 Date: October 2017
0279 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0280 Description: Shows the number of dirty segments.
0281
0282 What: /sys/fs/f2fs/<disk>/reserved_blocks
0283 Date: June 2017
0284 Contact: "Chao Yu" <yuchao0@huawei.com>
0285 Description: Controls target reserved blocks in system, the threshold
0286 is soft, it could exceed current available user space.
0287
0288 What: /sys/fs/f2fs/<disk>/current_reserved_blocks
0289 Date: October 2017
0290 Contact: "Yunlong Song" <yunlong.song@huawei.com>
0291 Contact: "Chao Yu" <yuchao0@huawei.com>
0292 Description: Shows current reserved blocks in system, it may be temporarily
0293 smaller than target_reserved_blocks, but will gradually
0294 increase to target_reserved_blocks when more free blocks are
0295 freed by user later.
0296
0297 What: /sys/fs/f2fs/<disk>/gc_urgent
0298 Date: August 2017
0299 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0300 Description: Do background GC aggressively when set. Set to 0 by default.
0301 gc urgent high(1): does GC forcibly in a period of given
0302 gc_urgent_sleep_time and ignores I/O idling check. uses greedy
0303 GC approach and turns SSR mode on.
0304 gc urgent low(2): lowers the bar of checking I/O idling in
0305 order to process outstanding discard commands and GC a
0306 little bit aggressively. uses cost benefit GC approach.
0307 gc urgent mid(3): does GC forcibly in a period of given
0308 gc_urgent_sleep_time and executes a mid level of I/O idling check.
0309 uses cost benefit GC approach.
0310
0311 What: /sys/fs/f2fs/<disk>/gc_urgent_sleep_time
0312 Date: August 2017
0313 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0314 Description: Controls sleep time of GC urgent mode. Set to 500ms by default.
0315
0316 What: /sys/fs/f2fs/<disk>/readdir_ra
0317 Date: November 2017
0318 Contact: "Sheng Yong" <shengyong1@huawei.com>
0319 Description: Controls readahead inode block in readdir. Enabled by default.
0320
0321 What: /sys/fs/f2fs/<disk>/gc_pin_file_thresh
0322 Date: January 2018
0323 Contact: Jaegeuk Kim <jaegeuk@kernel.org>
0324 Description: This indicates how many GC can be failed for the pinned
0325 file. If it exceeds this, F2FS doesn't guarantee its pinning
0326 state. 2048 trials is set by default.
0327
0328 What: /sys/fs/f2fs/<disk>/extension_list
0329 Date: Feburary 2018
0330 Contact: "Chao Yu" <yuchao0@huawei.com>
0331 Description: Used to control configure extension list:
0332 - Query: cat /sys/fs/f2fs/<disk>/extension_list
0333 - Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list
0334 - Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list
0335 - [h] means add/del hot file extension
0336 - [c] means add/del cold file extension
0337
0338 What: /sys/fs/f2fs/<disk>/unusable
0339 Date April 2019
0340 Contact: "Daniel Rosenberg" <drosen@google.com>
0341 Description: If checkpoint=disable, it displays the number of blocks that
0342 are unusable.
0343 If checkpoint=enable it displays the number of blocks that
0344 would be unusable if checkpoint=disable were to be set.
0345
0346 What: /sys/fs/f2fs/<disk>/encoding
0347 Date July 2019
0348 Contact: "Daniel Rosenberg" <drosen@google.com>
0349 Description: Displays name and version of the encoding set for the filesystem.
0350 If no encoding is set, displays (none)
0351
0352 What: /sys/fs/f2fs/<disk>/free_segments
0353 Date: September 2019
0354 Contact: "Hridya Valsaraju" <hridya@google.com>
0355 Description: Number of free segments in disk.
0356
0357 What: /sys/fs/f2fs/<disk>/cp_foreground_calls
0358 Date: September 2019
0359 Contact: "Hridya Valsaraju" <hridya@google.com>
0360 Description: Number of checkpoint operations performed on demand. Available when
0361 CONFIG_F2FS_STAT_FS=y.
0362
0363 What: /sys/fs/f2fs/<disk>/cp_background_calls
0364 Date: September 2019
0365 Contact: "Hridya Valsaraju" <hridya@google.com>
0366 Description: Number of checkpoint operations performed in the background to
0367 free segments. Available when CONFIG_F2FS_STAT_FS=y.
0368
0369 What: /sys/fs/f2fs/<disk>/gc_foreground_calls
0370 Date: September 2019
0371 Contact: "Hridya Valsaraju" <hridya@google.com>
0372 Description: Number of garbage collection operations performed on demand.
0373 Available when CONFIG_F2FS_STAT_FS=y.
0374
0375 What: /sys/fs/f2fs/<disk>/gc_background_calls
0376 Date: September 2019
0377 Contact: "Hridya Valsaraju" <hridya@google.com>
0378 Description: Number of garbage collection operations triggered in background.
0379 Available when CONFIG_F2FS_STAT_FS=y.
0380
0381 What: /sys/fs/f2fs/<disk>/moved_blocks_foreground
0382 Date: September 2019
0383 Contact: "Hridya Valsaraju" <hridya@google.com>
0384 Description: Number of blocks moved by garbage collection in foreground.
0385 Available when CONFIG_F2FS_STAT_FS=y.
0386
0387 What: /sys/fs/f2fs/<disk>/moved_blocks_background
0388 Date: September 2019
0389 Contact: "Hridya Valsaraju" <hridya@google.com>
0390 Description: Number of blocks moved by garbage collection in background.
0391 Available when CONFIG_F2FS_STAT_FS=y.
0392
0393 What: /sys/fs/f2fs/<disk>/avg_vblocks
0394 Date: September 2019
0395 Contact: "Hridya Valsaraju" <hridya@google.com>
0396 Description: Average number of valid blocks.
0397 Available when CONFIG_F2FS_STAT_FS=y.
0398
0399 What: /sys/fs/f2fs/<disk>/mounted_time_sec
0400 Date: February 2020
0401 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0402 Description: Show the mounted time in secs of this partition.
0403
0404 What: /sys/fs/f2fs/<disk>/data_io_flag
0405 Date: April 2020
0406 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0407 Description: Give a way to attach REQ_META|FUA to data writes
0408 given temperature-based bits. Now the bits indicate:
0409
0410 +-------------------+-------------------+
0411 | REQ_META | REQ_FUA |
0412 +------+------+-----+------+------+-----+
0413 | 5 | 4 | 3 | 2 | 1 | 0 |
0414 +------+------+-----+------+------+-----+
0415 | Cold | Warm | Hot | Cold | Warm | Hot |
0416 +------+------+-----+------+------+-----+
0417
0418 What: /sys/fs/f2fs/<disk>/node_io_flag
0419 Date: June 2020
0420 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0421 Description: Give a way to attach REQ_META|FUA to node writes
0422 given temperature-based bits. Now the bits indicate:
0423
0424 +-------------------+-------------------+
0425 | REQ_META | REQ_FUA |
0426 +------+------+-----+------+------+-----+
0427 | 5 | 4 | 3 | 2 | 1 | 0 |
0428 +------+------+-----+------+------+-----+
0429 | Cold | Warm | Hot | Cold | Warm | Hot |
0430 +------+------+-----+------+------+-----+
0431
0432 What: /sys/fs/f2fs/<disk>/iostat_period_ms
0433 Date: April 2020
0434 Contact: "Daeho Jeong" <daehojeong@google.com>
0435 Description: Give a way to change iostat_period time. 3secs by default.
0436 The new iostat trace gives stats gap given the period.
0437 What: /sys/fs/f2fs/<disk>/max_io_bytes
0438 Date: December 2020
0439 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0440 Description: This gives a control to limit the bio size in f2fs.
0441 Default is zero, which will follow underlying block layer limit,
0442 whereas, if it has a certain bytes value, f2fs won't submit a
0443 bio larger than that size.
0444
0445 What: /sys/fs/f2fs/<disk>/stat/sb_status
0446 Date: December 2020
0447 Contact: "Chao Yu" <yuchao0@huawei.com>
0448 Description: Show status of f2fs superblock in real time.
0449
0450 ====== ===================== =================================
0451 value sb status macro description
0452 0x1 SBI_IS_DIRTY dirty flag for checkpoint
0453 0x2 SBI_IS_CLOSE specify unmounting
0454 0x4 SBI_NEED_FSCK need fsck.f2fs to fix
0455 0x8 SBI_POR_DOING recovery is doing or not
0456 0x10 SBI_NEED_SB_WRITE need to recover superblock
0457 0x20 SBI_NEED_CP need to checkpoint
0458 0x40 SBI_IS_SHUTDOWN shutdown by ioctl
0459 0x80 SBI_IS_RECOVERED recovered orphan/data
0460 0x100 SBI_CP_DISABLED CP was disabled last mount
0461 0x200 SBI_CP_DISABLED_QUICK CP was disabled quickly
0462 0x400 SBI_QUOTA_NEED_FLUSH need to flush quota info in CP
0463 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP
0464 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted
0465 0x2000 SBI_IS_RESIZEFS resizefs is in process
0466 0x4000 SBI_IS_FREEZING freefs is in process
0467 ====== ===================== =================================
0468
0469 What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio
0470 Date: January 2021
0471 Contact: "Daeho Jeong" <daehojeong@google.com>
0472 Description: Give a way to change checkpoint merge daemon's io priority.
0473 Its default value is "be,3", which means "BE" I/O class and
0474 I/O priority "3". We can select the class between "rt" and "be",
0475 and set the I/O priority within valid range of it. "," delimiter
0476 is necessary in between I/O class and priority number.
0477
0478 What: /sys/fs/f2fs/<disk>/ovp_segments
0479 Date: March 2021
0480 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0481 Description: Shows the number of overprovision segments.
0482
0483 What: /sys/fs/f2fs/<disk>/compr_written_block
0484 Date: March 2021
0485 Contact: "Daeho Jeong" <daehojeong@google.com>
0486 Description: Show the block count written after compression since mount. Note
0487 that when the compressed blocks are deleted, this count doesn't
0488 decrease. If you write "0" here, you can initialize
0489 compr_written_block and compr_saved_block to "0".
0490
0491 What: /sys/fs/f2fs/<disk>/compr_saved_block
0492 Date: March 2021
0493 Contact: "Daeho Jeong" <daehojeong@google.com>
0494 Description: Show the saved block count with compression since mount. Note
0495 that when the compressed blocks are deleted, this count doesn't
0496 decrease. If you write "0" here, you can initialize
0497 compr_written_block and compr_saved_block to "0".
0498
0499 What: /sys/fs/f2fs/<disk>/compr_new_inode
0500 Date: March 2021
0501 Contact: "Daeho Jeong" <daehojeong@google.com>
0502 Description: Show the count of inode newly enabled for compression since mount.
0503 Note that when the compression is disabled for the files, this count
0504 doesn't decrease. If you write "0" here, you can initialize
0505 compr_new_inode to "0".
0506
0507 What: /sys/fs/f2fs/<disk>/atgc_candidate_ratio
0508 Date: May 2021
0509 Contact: "Chao Yu" <yuchao0@huawei.com>
0510 Description: When ATGC is on, it controls candidate ratio in order to limit total
0511 number of potential victim in all candidates, the value should be in
0512 range of [0, 100], by default it was initialized as 20(%).
0513
0514 What: /sys/fs/f2fs/<disk>/atgc_candidate_count
0515 Date: May 2021
0516 Contact: "Chao Yu" <yuchao0@huawei.com>
0517 Description: When ATGC is on, it controls candidate count in order to limit total
0518 number of potential victim in all candidates, by default it was
0519 initialized as 10 (sections).
0520
0521 What: /sys/fs/f2fs/<disk>/atgc_age_weight
0522 Date: May 2021
0523 Contact: "Chao Yu" <yuchao0@huawei.com>
0524 Description: When ATGC is on, it controls age weight to balance weight proportion
0525 in between aging and valid blocks, the value should be in range of
0526 [0, 100], by default it was initialized as 60(%).
0527
0528 What: /sys/fs/f2fs/<disk>/atgc_age_threshold
0529 Date: May 2021
0530 Contact: "Chao Yu" <yuchao0@huawei.com>
0531 Description: When ATGC is on, it controls age threshold to bypass GCing young
0532 candidates whose age is not beyond the threshold, by default it was
0533 initialized as 604800 seconds (equals to 7 days).
0534
0535 What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments
0536 Date: July 2021
0537 Contact: "Daeho Jeong" <daehojeong@google.com>
0538 Description: Show how many segments have been reclaimed by GC during a specific
0539 GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy,
0540 3: GC idle AT, 4: GC urgent high, 5: GC urgent low 6: GC urgent mid)
0541 You can re-initialize this value to "0".
0542
0543 What: /sys/fs/f2fs/<disk>/gc_segment_mode
0544 Date: July 2021
0545 Contact: "Daeho Jeong" <daehojeong@google.com>
0546 Description: You can control for which gc mode the "gc_reclaimed_segments" node shows.
0547 Refer to the description of the modes in "gc_reclaimed_segments".
0548
0549 What: /sys/fs/f2fs/<disk>/seq_file_ra_mul
0550 Date: July 2021
0551 Contact: "Daeho Jeong" <daehojeong@google.com>
0552 Description: You can control the multiplier value of bdi device readahead window size
0553 between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option.
0554
0555 What: /sys/fs/f2fs/<disk>/max_fragment_chunk
0556 Date: August 2021
0557 Contact: "Daeho Jeong" <daehojeong@google.com>
0558 Description: With "mode=fragment:block" mount options, we can scatter block allocation.
0559 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole
0560 in the length of 1..<max_fragment_hole> by turns. This value can be set
0561 between 1..512 and the default value is 4.
0562
0563 What: /sys/fs/f2fs/<disk>/max_fragment_hole
0564 Date: August 2021
0565 Contact: "Daeho Jeong" <daehojeong@google.com>
0566 Description: With "mode=fragment:block" mount options, we can scatter block allocation.
0567 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole
0568 in the length of 1..<max_fragment_hole> by turns. This value can be set
0569 between 1..512 and the default value is 4.
0570
0571 What: /sys/fs/f2fs/<disk>/gc_urgent_high_remaining
0572 Date: December 2021
0573 Contact: "Daeho Jeong" <daehojeong@google.com>
0574 Description: You can set the trial count limit for GC urgent high mode with this value.
0575 If GC thread gets to the limit, the mode will turn back to GC normal mode.
0576 By default, the value is zero, which means there is no limit like before.
0577
0578 What: /sys/fs/f2fs/<disk>/max_roll_forward_node_blocks
0579 Date: January 2022
0580 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0581 Description: Controls max # of node block writes to be used for roll forward
0582 recovery. This can limit the roll forward recovery time.
0583
0584 What: /sys/fs/f2fs/<disk>/unusable_blocks_per_sec
0585 Date: June 2022
0586 Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
0587 Description: Shows the number of unusable blocks in a section which was defined by
0588 the zone capacity reported by underlying zoned device.
0589
0590 What: /sys/fs/f2fs/<disk>/current_atomic_write
0591 Date: July 2022
0592 Contact: "Daeho Jeong" <daehojeong@google.com>
0593 Description: Show the total current atomic write block count, which is not committed yet.
0594 This is a read-only entry.
0595
0596 What: /sys/fs/f2fs/<disk>/peak_atomic_write
0597 Date: July 2022
0598 Contact: "Daeho Jeong" <daehojeong@google.com>
0599 Description: Show the peak value of total current atomic write block count after boot.
0600 If you write "0" here, you can initialize to "0".
0601
0602 What: /sys/fs/f2fs/<disk>/committed_atomic_block
0603 Date: July 2022
0604 Contact: "Daeho Jeong" <daehojeong@google.com>
0605 Description: Show the accumulated total committed atomic write block count after boot.
0606 If you write "0" here, you can initialize to "0".
0607
0608 What: /sys/fs/f2fs/<disk>/revoked_atomic_block
0609 Date: July 2022
0610 Contact: "Daeho Jeong" <daehojeong@google.com>
0611 Description: Show the accumulated total revoked atomic write block count after boot.
0612 If you write "0" here, you can initialize to "0".
