1What: /sys/fs/f2fs/<disk>/gc_max_sleep_time 2Date: July 2013 3Contact: "Namjae Jeon" <namjae.jeon@samsung.com> 4Description: Controls the maximum sleep time for gc_thread. Time 5 is in milliseconds. 6 7What: /sys/fs/f2fs/<disk>/gc_min_sleep_time 8Date: July 2013 9Contact: "Namjae Jeon" <namjae.jeon@samsung.com> 10Description: Controls the minimum sleep time for gc_thread. Time 11 is in milliseconds. 12 13What: /sys/fs/f2fs/<disk>/gc_no_gc_sleep_time 14Date: July 2013 15Contact: "Namjae Jeon" <namjae.jeon@samsung.com> 16Description: Controls the default sleep time for gc_thread. Time 17 is in milliseconds. 18 19What: /sys/fs/f2fs/<disk>/gc_idle 20Date: July 2013 21Contact: "Namjae Jeon" <namjae.jeon@samsung.com> 22Description: Controls the victim selection policy for garbage collection. 23 Setting gc_idle = 0(default) will disable this option. Setting: 24 25 =========== =============================================== 26 gc_idle = 1 will select the Cost Benefit approach & setting 27 gc_idle = 2 will select the greedy approach & setting 28 gc_idle = 3 will select the age-threshold based approach. 29 =========== =============================================== 30 31What: /sys/fs/f2fs/<disk>/reclaim_segments 32Date: October 2013 33Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 34Description: This parameter controls the number of prefree segments to be 35 reclaimed. If the number of prefree segments is larger than 36 the number of segments in the proportion to the percentage 37 over total volume size, f2fs tries to conduct checkpoint to 38 reclaim the prefree segments to free segments. 39 By default, 5% over total # of segments. 40 41What: /sys/fs/f2fs/<disk>/main_blkaddr 42Date: November 2019 43Contact: "Ramon Pantin" <pantin@google.com> 44Description: Shows first block address of MAIN area. 45 46What: /sys/fs/f2fs/<disk>/ipu_policy 47Date: November 2013 48Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 49Description: Controls the in-place-update policy. 50 updates in f2fs. User can set: 51 52 ===== =============== =================================================== 53 value policy description 54 0x00 DISABLE disable IPU(=default option in LFS mode) 55 0x01 FORCE all the time 56 0x02 SSR if SSR mode is activated 57 0x04 UTIL if FS utilization is over threshold 58 0x08 SSR_UTIL if SSR mode is activated and FS utilization is over 59 threshold 60 0x10 FSYNC activated in fsync path only for high performance 61 flash storages. IPU will be triggered only if the 62 # of dirty pages over min_fsync_blocks. 63 (=default option) 64 0x20 ASYNC do IPU given by asynchronous write requests 65 0x40 NOCACHE disable IPU bio cache 66 0x80 HONOR_OPU_WRITE use OPU write prior to IPU write if inode has 67 FI_OPU_WRITE flag 68 ===== =============== =================================================== 69 70 Refer segment.h for details. 71 72What: /sys/fs/f2fs/<disk>/min_ipu_util 73Date: November 2013 74Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 75Description: Controls the FS utilization condition for the in-place-update 76 policies. It is used by F2FS_IPU_UTIL and F2FS_IPU_SSR_UTIL policies. 77 78What: /sys/fs/f2fs/<disk>/min_fsync_blocks 79Date: September 2014 80Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 81Description: Controls the dirty page count condition for the in-place-update 82 policies. 83 84What: /sys/fs/f2fs/<disk>/min_seq_blocks 85Date: August 2018 86Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 87Description: Controls the dirty page count condition for batched sequential 88 writes in writepages. 89 90What: /sys/fs/f2fs/<disk>/min_hot_blocks 91Date: March 2017 92Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 93Description: Controls the dirty page count condition for redefining hot data. 94 95What: /sys/fs/f2fs/<disk>/min_ssr_sections 96Date: October 2017 97Contact: "Chao Yu" <yuchao0@huawei.com> 98Description: Controls the free section threshold to trigger SSR allocation. 99 If this is large, SSR mode will be enabled early. 100 101What: /sys/fs/f2fs/<disk>/max_small_discards 102Date: November 2013 103Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 104Description: Controls the issue rate of discard commands that consist of small 105 blocks less than 2MB. The candidates to be discarded are cached during 106 checkpoint, and issued by issue_discard thread after checkpoint. 107 It is enabled by default. 108 109What: /sys/fs/f2fs/<disk>/max_ordered_discard 110Date: October 2022 111Contact: "Yangtao Li" <frank.li@vivo.com> 112Description: Controls the maximum ordered discard, the unit size is one block(4KB). 113 Set it to 16 by default. 114 115What: /sys/fs/f2fs/<disk>/max_discard_request 116Date: December 2021 117Contact: "Konstantin Vyshetsky" <vkon@google.com> 118Description: Controls the number of discards a thread will issue at a time. 119 Higher number will allow the discard thread to finish its work 120 faster, at the cost of higher latency for incoming I/O. 121 122What: /sys/fs/f2fs/<disk>/min_discard_issue_time 123Date: December 2021 124Contact: "Konstantin Vyshetsky" <vkon@google.com> 125Description: Controls the interval the discard thread will wait between 126 issuing discard requests when there are discards to be issued and 127 no I/O aware interruptions occur. 128 129What: /sys/fs/f2fs/<disk>/mid_discard_issue_time 130Date: December 2021 131Contact: "Konstantin Vyshetsky" <vkon@google.com> 132Description: Controls the interval the discard thread will wait between 133 issuing discard requests when there are discards to be issued and 134 an I/O aware interruption occurs. 135 136What: /sys/fs/f2fs/<disk>/max_discard_issue_time 137Date: December 2021 138Contact: "Konstantin Vyshetsky" <vkon@google.com> 139Description: Controls the interval the discard thread will wait when there are 140 no discard operations to be issued. 141 142What: /sys/fs/f2fs/<disk>/discard_granularity 143Date: July 2017 144Contact: "Chao Yu" <yuchao0@huawei.com> 145Description: Controls discard granularity of inner discard thread. Inner thread 146 will not issue discards with size that is smaller than granularity. 147 The unit size is one block(4KB), now only support configuring 148 in range of [1, 512]. Default value is 16. 149 For small devices, default value is 1. 150 151What: /sys/fs/f2fs/<disk>/umount_discard_timeout 152Date: January 2019 153Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 154Description: Set timeout to issue discard commands during umount. 155 Default: 5 secs 156 157What: /sys/fs/f2fs/<disk>/pending_discard 158Date: November 2021 159Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 160Description: Shows the number of pending discard commands in the queue. 161 162What: /sys/fs/f2fs/<disk>/max_victim_search 163Date: January 2014 164Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 165Description: Controls the number of trials to find a victim segment 166 when conducting SSR and cleaning operations. The default value 167 is 4096 which covers 8GB block address range. 168 169What: /sys/fs/f2fs/<disk>/migration_granularity 170Date: October 2018 171Contact: "Chao Yu" <yuchao0@huawei.com> 172Description: Controls migration granularity of garbage collection on large 173 section, it can let GC move partial segment{s} of one section 174 in one GC cycle, so that dispersing heavy overhead GC to 175 multiple lightweight one. 176 177What: /sys/fs/f2fs/<disk>/dir_level 178Date: March 2014 179Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 180Description: Controls the directory level for large directory. If a 181 directory has a number of files, it can reduce the file lookup 182 latency by increasing this dir_level value. Otherwise, it 183 needs to decrease this value to reduce the space overhead. 184 The default value is 0. 185 186What: /sys/fs/f2fs/<disk>/ram_thresh 187Date: March 2014 188Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> 189Description: Controls the memory footprint used by free nids and cached 190 nat entries. By default, 1 is set, which indicates 191 10 MB / 1 GB RAM. 192 193What: /sys/fs/f2fs/<disk>/cp_interval 194Date: October 2015 195Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 196Description: Controls the checkpoint timing, set to 60 seconds by default. 197 198What: /sys/fs/f2fs/<disk>/idle_interval 199Date: January 2016 200Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 201Description: Controls the idle timing of system, if there is no FS operation 202 during given interval. 203 Set to 5 seconds by default. 204 205What: /sys/fs/f2fs/<disk>/discard_idle_interval 206Date: September 2018 207Contact: "Chao Yu" <yuchao0@huawei.com> 208Contact: "Sahitya Tummala" <quic_stummala@quicinc.com> 209Description: Controls the idle timing of discard thread given 210 this time interval. 211 Default is 5 secs. 212 213What: /sys/fs/f2fs/<disk>/gc_idle_interval 214Date: September 2018 215Contact: "Chao Yu" <yuchao0@huawei.com> 216Contact: "Sahitya Tummala" <quic_stummala@quicinc.com> 217Description: Controls the idle timing for gc path. Set to 5 seconds by default. 218 219What: /sys/fs/f2fs/<disk>/iostat_enable 220Date: August 2017 221Contact: "Chao Yu" <yuchao0@huawei.com> 222Description: Controls to enable/disable IO stat. 223 224What: /sys/fs/f2fs/<disk>/ra_nid_pages 225Date: October 2015 226Contact: "Chao Yu" <chao2.yu@samsung.com> 227Description: Controls the count of nid pages to be readaheaded. 228 When building free nids, F2FS reads NAT blocks ahead for 229 speed up. Default is 0. 230 231What: /sys/fs/f2fs/<disk>/dirty_nats_ratio 232Date: January 2016 233Contact: "Chao Yu" <chao2.yu@samsung.com> 234Description: Controls dirty nat entries ratio threshold, if current 235 ratio exceeds configured threshold, checkpoint will 236 be triggered for flushing dirty nat entries. 237 238What: /sys/fs/f2fs/<disk>/lifetime_write_kbytes 239Date: January 2016 240Contact: "Shuoran Liu" <liushuoran@huawei.com> 241Description: Shows total written kbytes issued to disk. 242 243What: /sys/fs/f2fs/<disk>/features 244Date: July 2017 245Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 246Description: <deprecated: should use /sys/fs/f2fs/<disk>/feature_list/> 247 Shows all enabled features in current device. 248 Supported features: 249 encryption, blkzoned, extra_attr, projquota, inode_checksum, 250 flexible_inline_xattr, quota_ino, inode_crtime, lost_found, 251 verity, sb_checksum, casefold, readonly, compression, pin_file. 252 253What: /sys/fs/f2fs/<disk>/feature_list/ 254Date: June 2021 255Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 256Description: Expand /sys/fs/f2fs/<disk>/features to meet sysfs rule. 257 Supported on-disk features: 258 encryption, block_zoned (aka blkzoned), extra_attr, 259 project_quota (aka projquota), inode_checksum, 260 flexible_inline_xattr, quota_ino, inode_crtime, lost_found, 261 verity, sb_checksum, casefold, readonly, compression. 262 Note that, pin_file is moved into /sys/fs/f2fs/features/. 263 264What: /sys/fs/f2fs/features/ 265Date: July 2017 266Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 267Description: Shows all enabled kernel features. 268 Supported features: 269 encryption, block_zoned, extra_attr, project_quota, 270 inode_checksum, flexible_inline_xattr, quota_ino, 271 inode_crtime, lost_found, verity, sb_checksum, 272 casefold, readonly, compression, test_dummy_encryption_v2, 273 atomic_write, pin_file, encrypted_casefold. 274 275What: /sys/fs/f2fs/<disk>/inject_rate 276Date: May 2016 277Contact: "Sheng Yong" <shengyong1@huawei.com> 278Description: Controls the injection rate of arbitrary faults. 279 280What: /sys/fs/f2fs/<disk>/inject_type 281Date: May 2016 282Contact: "Sheng Yong" <shengyong1@huawei.com> 283Description: Controls the injection type of arbitrary faults. 284 285What: /sys/fs/f2fs/<disk>/dirty_segments 286Date: October 2017 287Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 288Description: Shows the number of dirty segments. 289 290What: /sys/fs/f2fs/<disk>/reserved_blocks 291Date: June 2017 292Contact: "Chao Yu" <yuchao0@huawei.com> 293Description: Controls target reserved blocks in system, the threshold 294 is soft, it could exceed current available user space. 295 296What: /sys/fs/f2fs/<disk>/current_reserved_blocks 297Date: October 2017 298Contact: "Yunlong Song" <yunlong.song@huawei.com> 299Contact: "Chao Yu" <yuchao0@huawei.com> 300Description: Shows current reserved blocks in system, it may be temporarily 301 smaller than target_reserved_blocks, but will gradually 302 increase to target_reserved_blocks when more free blocks are 303 freed by user later. 304 305What: /sys/fs/f2fs/<disk>/gc_urgent 306Date: August 2017 307Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 308Description: Do background GC aggressively when set. Set to 0 by default. 309 gc urgent high(1): does GC forcibly in a period of given 310 gc_urgent_sleep_time and ignores I/O idling check. uses greedy 311 GC approach and turns SSR mode on. 312 gc urgent low(2): lowers the bar of checking I/O idling in 313 order to process outstanding discard commands and GC a 314 little bit aggressively. always uses cost benefit GC approach, 315 and will override age-threshold GC approach if ATGC is enabled 316 at the same time. 317 gc urgent mid(3): does GC forcibly in a period of given 318 gc_urgent_sleep_time and executes a mid level of I/O idling check. 319 always uses cost benefit GC approach, and will override 320 age-threshold GC approach if ATGC is enabled at the same time. 321 322What: /sys/fs/f2fs/<disk>/gc_urgent_sleep_time 323Date: August 2017 324Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 325Description: Controls sleep time of GC urgent mode. Set to 500ms by default. 326 327What: /sys/fs/f2fs/<disk>/readdir_ra 328Date: November 2017 329Contact: "Sheng Yong" <shengyong1@huawei.com> 330Description: Controls readahead inode block in readdir. Enabled by default. 331 332What: /sys/fs/f2fs/<disk>/gc_pin_file_thresh 333Date: January 2018 334Contact: Jaegeuk Kim <jaegeuk@kernel.org> 335Description: This indicates how many GC can be failed for the pinned 336 file. If it exceeds this, F2FS doesn't guarantee its pinning 337 state. 2048 trials is set by default, and 65535 as maximum. 338 339What: /sys/fs/f2fs/<disk>/extension_list 340Date: February 2018 341Contact: "Chao Yu" <yuchao0@huawei.com> 342Description: Used to control configure extension list: 343 - Query: cat /sys/fs/f2fs/<disk>/extension_list 344 - Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list 345 - Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list 346 - [h] means add/del hot file extension 347 - [c] means add/del cold file extension 348 349What: /sys/fs/f2fs/<disk>/unusable 350Date April 2019 351Contact: "Daniel Rosenberg" <drosen@google.com> 352Description: If checkpoint=disable, it displays the number of blocks that 353 are unusable. 354 If checkpoint=enable it displays the number of blocks that 355 would be unusable if checkpoint=disable were to be set. 356 357What: /sys/fs/f2fs/<disk>/encoding 358Date July 2019 359Contact: "Daniel Rosenberg" <drosen@google.com> 360Description: Displays name and version of the encoding set for the filesystem. 361 If no encoding is set, displays (none) 362 363What: /sys/fs/f2fs/<disk>/free_segments 364Date: September 2019 365Contact: "Hridya Valsaraju" <hridya@google.com> 366Description: Number of free segments in disk. 367 368What: /sys/fs/f2fs/<disk>/cp_foreground_calls 369Date: September 2019 370Contact: "Hridya Valsaraju" <hridya@google.com> 371Description: Number of checkpoint operations performed on demand. Available when 372 CONFIG_F2FS_STAT_FS=y. 373 374What: /sys/fs/f2fs/<disk>/cp_background_calls 375Date: September 2019 376Contact: "Hridya Valsaraju" <hridya@google.com> 377Description: Number of checkpoint operations performed in the background to 378 free segments. Available when CONFIG_F2FS_STAT_FS=y. 379 380What: /sys/fs/f2fs/<disk>/gc_foreground_calls 381Date: September 2019 382Contact: "Hridya Valsaraju" <hridya@google.com> 383Description: Number of garbage collection operations performed on demand. 384 Available when CONFIG_F2FS_STAT_FS=y. 385 386What: /sys/fs/f2fs/<disk>/gc_background_calls 387Date: September 2019 388Contact: "Hridya Valsaraju" <hridya@google.com> 389Description: Number of garbage collection operations triggered in background. 390 Available when CONFIG_F2FS_STAT_FS=y. 391 392What: /sys/fs/f2fs/<disk>/moved_blocks_foreground 393Date: September 2019 394Contact: "Hridya Valsaraju" <hridya@google.com> 395Description: Number of blocks moved by garbage collection in foreground. 396 Available when CONFIG_F2FS_STAT_FS=y. 397 398What: /sys/fs/f2fs/<disk>/moved_blocks_background 399Date: September 2019 400Contact: "Hridya Valsaraju" <hridya@google.com> 401Description: Number of blocks moved by garbage collection in background. 402 Available when CONFIG_F2FS_STAT_FS=y. 403 404What: /sys/fs/f2fs/<disk>/avg_vblocks 405Date: September 2019 406Contact: "Hridya Valsaraju" <hridya@google.com> 407Description: Average number of valid blocks. 408 Available when CONFIG_F2FS_STAT_FS=y. 409 410What: /sys/fs/f2fs/<disk>/mounted_time_sec 411Date: February 2020 412Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 413Description: Show the mounted time in secs of this partition. 414 415What: /sys/fs/f2fs/<disk>/data_io_flag 416Date: April 2020 417Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 418Description: Give a way to attach REQ_META|FUA to data writes 419 given temperature-based bits. Now the bits indicate: 420 421 +-------------------+-------------------+ 422 | REQ_META | REQ_FUA | 423 +------+------+-----+------+------+-----+ 424 | 5 | 4 | 3 | 2 | 1 | 0 | 425 +------+------+-----+------+------+-----+ 426 | Cold | Warm | Hot | Cold | Warm | Hot | 427 +------+------+-----+------+------+-----+ 428 429What: /sys/fs/f2fs/<disk>/node_io_flag 430Date: June 2020 431Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 432Description: Give a way to attach REQ_META|FUA to node writes 433 given temperature-based bits. Now the bits indicate: 434 435 +-------------------+-------------------+ 436 | REQ_META | REQ_FUA | 437 +------+------+-----+------+------+-----+ 438 | 5 | 4 | 3 | 2 | 1 | 0 | 439 +------+------+-----+------+------+-----+ 440 | Cold | Warm | Hot | Cold | Warm | Hot | 441 +------+------+-----+------+------+-----+ 442 443What: /sys/fs/f2fs/<disk>/iostat_period_ms 444Date: April 2020 445Contact: "Daeho Jeong" <daehojeong@google.com> 446Description: Give a way to change iostat_period time. 3secs by default. 447 The new iostat trace gives stats gap given the period. 448What: /sys/fs/f2fs/<disk>/max_io_bytes 449Date: December 2020 450Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 451Description: This gives a control to limit the bio size in f2fs. 452 Default is zero, which will follow underlying block layer limit, 453 whereas, if it has a certain bytes value, f2fs won't submit a 454 bio larger than that size. 455 456What: /sys/fs/f2fs/<disk>/stat/sb_status 457Date: December 2020 458Contact: "Chao Yu" <yuchao0@huawei.com> 459Description: Show status of f2fs superblock in real time. 460 461 ====== ===================== ================================= 462 value sb status macro description 463 0x1 SBI_IS_DIRTY dirty flag for checkpoint 464 0x2 SBI_IS_CLOSE specify unmounting 465 0x4 SBI_NEED_FSCK need fsck.f2fs to fix 466 0x8 SBI_POR_DOING recovery is doing or not 467 0x10 SBI_NEED_SB_WRITE need to recover superblock 468 0x20 SBI_NEED_CP need to checkpoint 469 0x40 SBI_IS_SHUTDOWN shutdown by ioctl 470 0x80 SBI_IS_RECOVERED recovered orphan/data 471 0x100 SBI_CP_DISABLED CP was disabled last mount 472 0x200 SBI_CP_DISABLED_QUICK CP was disabled quickly 473 0x400 SBI_QUOTA_NEED_FLUSH need to flush quota info in CP 474 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP 475 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted 476 0x2000 SBI_IS_RESIZEFS resizefs is in process 477 0x4000 SBI_IS_FREEZING freefs is in process 478 ====== ===================== ================================= 479 480What: /sys/fs/f2fs/<disk>/stat/cp_status 481Date: September 2022 482Contact: "Chao Yu" <chao.yu@oppo.com> 483Description: Show status of f2fs checkpoint in real time. 484 485 =============================== ============================== 486 cp flag value 487 CP_UMOUNT_FLAG 0x00000001 488 CP_ORPHAN_PRESENT_FLAG 0x00000002 489 CP_COMPACT_SUM_FLAG 0x00000004 490 CP_ERROR_FLAG 0x00000008 491 CP_FSCK_FLAG 0x00000010 492 CP_FASTBOOT_FLAG 0x00000020 493 CP_CRC_RECOVERY_FLAG 0x00000040 494 CP_NAT_BITS_FLAG 0x00000080 495 CP_TRIMMED_FLAG 0x00000100 496 CP_NOCRC_RECOVERY_FLAG 0x00000200 497 CP_LARGE_NAT_BITMAP_FLAG 0x00000400 498 CP_QUOTA_NEED_FSCK_FLAG 0x00000800 499 CP_DISABLED_FLAG 0x00001000 500 CP_DISABLED_QUICK_FLAG 0x00002000 501 CP_RESIZEFS_FLAG 0x00004000 502 =============================== ============================== 503 504What: /sys/fs/f2fs/<disk>/stat/issued_discard 505Date: December 2023 506Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 507Description: Shows the number of issued discard. 508 509What: /sys/fs/f2fs/<disk>/stat/queued_discard 510Date: December 2023 511Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 512Description: Shows the number of queued discard. 513 514What: /sys/fs/f2fs/<disk>/stat/undiscard_blks 515Date: December 2023 516Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 517Description: Shows the total number of undiscard blocks. 518 519What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio 520Date: January 2021 521Contact: "Daeho Jeong" <daehojeong@google.com> 522Description: Give a way to change checkpoint merge daemon's io priority. 523 Its default value is "be,3", which means "BE" I/O class and 524 I/O priority "3". We can select the class between "rt" and "be", 525 and set the I/O priority within valid range of it. "," delimiter 526 is necessary in between I/O class and priority number. 527 528What: /sys/fs/f2fs/<disk>/ovp_segments 529Date: March 2021 530Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 531Description: Shows the number of overprovision segments. 532 533What: /sys/fs/f2fs/<disk>/compr_written_block 534Date: March 2021 535Contact: "Daeho Jeong" <daehojeong@google.com> 536Description: Show the block count written after compression since mount. Note 537 that when the compressed blocks are deleted, this count doesn't 538 decrease. If you write "0" here, you can initialize 539 compr_written_block and compr_saved_block to "0". 540 541What: /sys/fs/f2fs/<disk>/compr_saved_block 542Date: March 2021 543Contact: "Daeho Jeong" <daehojeong@google.com> 544Description: Show the saved block count with compression since mount. Note 545 that when the compressed blocks are deleted, this count doesn't 546 decrease. If you write "0" here, you can initialize 547 compr_written_block and compr_saved_block to "0". 548 549What: /sys/fs/f2fs/<disk>/compr_new_inode 550Date: March 2021 551Contact: "Daeho Jeong" <daehojeong@google.com> 552Description: Show the count of inode newly enabled for compression since mount. 553 Note that when the compression is disabled for the files, this count 554 doesn't decrease. If you write "0" here, you can initialize 555 compr_new_inode to "0". 556 557What: /sys/fs/f2fs/<disk>/atgc_candidate_ratio 558Date: May 2021 559Contact: "Chao Yu" <yuchao0@huawei.com> 560Description: When ATGC is on, it controls candidate ratio in order to limit total 561 number of potential victim in all candidates, the value should be in 562 range of [0, 100], by default it was initialized as 20(%). 563 564What: /sys/fs/f2fs/<disk>/atgc_candidate_count 565Date: May 2021 566Contact: "Chao Yu" <yuchao0@huawei.com> 567Description: When ATGC is on, it controls candidate count in order to limit total 568 number of potential victim in all candidates, by default it was 569 initialized as 10 (sections). 570 571What: /sys/fs/f2fs/<disk>/atgc_age_weight 572Date: May 2021 573Contact: "Chao Yu" <yuchao0@huawei.com> 574Description: When ATGC is on, it controls age weight to balance weight proportion 575 in between aging and valid blocks, the value should be in range of 576 [0, 100], by default it was initialized as 60(%). 577 578What: /sys/fs/f2fs/<disk>/atgc_age_threshold 579Date: May 2021 580Contact: "Chao Yu" <yuchao0@huawei.com> 581Description: When ATGC is on, it controls age threshold to bypass GCing young 582 candidates whose age is not beyond the threshold, by default it was 583 initialized as 604800 seconds (equals to 7 days). 584 585What: /sys/fs/f2fs/<disk>/atgc_enabled 586Date: Feb 2024 587Contact: "Jinbao Liu" <liujinbao1@xiaomi.com> 588Description: It represents whether ATGC is on or off. The value is 1 which 589 indicates that ATGC is on, and 0 indicates that it is off. 590 591What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments 592Date: July 2021 593Contact: "Daeho Jeong" <daehojeong@google.com> 594Description: Show how many segments have been reclaimed by GC during a specific 595 GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy, 596 3: GC idle AT, 4: GC urgent high, 5: GC urgent low 6: GC urgent mid) 597 You can re-initialize this value to "0". 598 599What: /sys/fs/f2fs/<disk>/gc_segment_mode 600Date: July 2021 601Contact: "Daeho Jeong" <daehojeong@google.com> 602Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. 603 Refer to the description of the modes in "gc_reclaimed_segments". 604 605What: /sys/fs/f2fs/<disk>/seq_file_ra_mul 606Date: July 2021 607Contact: "Daeho Jeong" <daehojeong@google.com> 608Description: You can control the multiplier value of bdi device readahead window size 609 between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. 610 611What: /sys/fs/f2fs/<disk>/max_fragment_chunk 612Date: August 2021 613Contact: "Daeho Jeong" <daehojeong@google.com> 614Description: With "mode=fragment:block" mount options, we can scatter block allocation. 615 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole 616 in the length of 1..<max_fragment_hole> by turns. This value can be set 617 between 1..512 and the default value is 4. 618 619What: /sys/fs/f2fs/<disk>/max_fragment_hole 620Date: August 2021 621Contact: "Daeho Jeong" <daehojeong@google.com> 622Description: With "mode=fragment:block" mount options, we can scatter block allocation. 623 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole 624 in the length of 1..<max_fragment_hole> by turns. This value can be set 625 between 1..512 and the default value is 4. 626 627What: /sys/fs/f2fs/<disk>/gc_remaining_trials 628Date: October 2022 629Contact: "Yangtao Li" <frank.li@vivo.com> 630Description: You can set the trial count limit for GC urgent and idle mode with this value. 631 If GC thread gets to the limit, the mode will turn back to GC normal mode. 632 By default, the value is zero, which means there is no limit like before. 633 634What: /sys/fs/f2fs/<disk>/max_roll_forward_node_blocks 635Date: January 2022 636Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 637Description: Controls max # of node block writes to be used for roll forward 638 recovery. This can limit the roll forward recovery time. 639 640What: /sys/fs/f2fs/<disk>/unusable_blocks_per_sec 641Date: June 2022 642Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 643Description: Shows the number of unusable blocks in a section which was defined by 644 the zone capacity reported by underlying zoned device. 645 646What: /sys/fs/f2fs/<disk>/current_atomic_write 647Date: July 2022 648Contact: "Daeho Jeong" <daehojeong@google.com> 649Description: Show the total current atomic write block count, which is not committed yet. 650 This is a read-only entry. 651 652What: /sys/fs/f2fs/<disk>/peak_atomic_write 653Date: July 2022 654Contact: "Daeho Jeong" <daehojeong@google.com> 655Description: Show the peak value of total current atomic write block count after boot. 656 If you write "0" here, you can initialize to "0". 657 658What: /sys/fs/f2fs/<disk>/committed_atomic_block 659Date: July 2022 660Contact: "Daeho Jeong" <daehojeong@google.com> 661Description: Show the accumulated total committed atomic write block count after boot. 662 If you write "0" here, you can initialize to "0". 663 664What: /sys/fs/f2fs/<disk>/revoked_atomic_block 665Date: July 2022 666Contact: "Daeho Jeong" <daehojeong@google.com> 667Description: Show the accumulated total revoked atomic write block count after boot. 668 If you write "0" here, you can initialize to "0". 669 670What: /sys/fs/f2fs/<disk>/gc_mode 671Date: October 2022 672Contact: "Yangtao Li" <frank.li@vivo.com> 673Description: Show the current gc_mode as a string. 674 This is a read-only entry. 675 676What: /sys/fs/f2fs/<disk>/discard_urgent_util 677Date: November 2022 678Contact: "Yangtao Li" <frank.li@vivo.com> 679Description: When space utilization exceeds this, do background DISCARD aggressively. 680 Does DISCARD forcibly in a period of given min_discard_issue_time when the number 681 of discards is not 0 and set discard granularity to 1. 682 Default: 80 683 684What: /sys/fs/f2fs/<disk>/hot_data_age_threshold 685Date: November 2022 686Contact: "Ping Xiong" <xiongping1@xiaomi.com> 687Description: When DATA SEPARATION is on, it controls the age threshold to indicate 688 the data blocks as hot. By default it was initialized as 262144 blocks 689 (equals to 1GB). 690 691What: /sys/fs/f2fs/<disk>/warm_data_age_threshold 692Date: November 2022 693Contact: "Ping Xiong" <xiongping1@xiaomi.com> 694Description: When DATA SEPARATION is on, it controls the age threshold to indicate 695 the data blocks as warm. By default it was initialized as 2621440 blocks 696 (equals to 10GB). 697 698What: /sys/fs/f2fs/<disk>/fault_rate 699Date: May 2016 700Contact: "Sheng Yong" <shengyong@oppo.com> 701Contact: "Chao Yu" <chao@kernel.org> 702Description: Enable fault injection in all supported types with 703 specified injection rate. 704 705What: /sys/fs/f2fs/<disk>/fault_type 706Date: May 2016 707Contact: "Sheng Yong" <shengyong@oppo.com> 708Contact: "Chao Yu" <chao@kernel.org> 709Description: Support configuring fault injection type, should be 710 enabled with fault_injection option, fault type value 711 is shown below, it supports single or combined type. 712 713 =========================== =========== 714 Type_Name Type_Value 715 =========================== =========== 716 FAULT_KMALLOC 0x000000001 717 FAULT_KVMALLOC 0x000000002 718 FAULT_PAGE_ALLOC 0x000000004 719 FAULT_PAGE_GET 0x000000008 720 FAULT_ALLOC_BIO 0x000000010 (obsolete) 721 FAULT_ALLOC_NID 0x000000020 722 FAULT_ORPHAN 0x000000040 723 FAULT_BLOCK 0x000000080 724 FAULT_DIR_DEPTH 0x000000100 725 FAULT_EVICT_INODE 0x000000200 726 FAULT_TRUNCATE 0x000000400 727 FAULT_READ_IO 0x000000800 728 FAULT_CHECKPOINT 0x000001000 729 FAULT_DISCARD 0x000002000 730 FAULT_WRITE_IO 0x000004000 731 FAULT_SLAB_ALLOC 0x000008000 732 FAULT_DQUOT_INIT 0x000010000 733 FAULT_LOCK_OP 0x000020000 734 FAULT_BLKADDR_VALIDITY 0x000040000 735 FAULT_BLKADDR_CONSISTENCE 0x000080000 736 FAULT_NO_SEGMENT 0x000100000 737 =========================== =========== 738 739What: /sys/fs/f2fs/<disk>/discard_io_aware_gran 740Date: January 2023 741Contact: "Yangtao Li" <frank.li@vivo.com> 742Description: Controls background discard granularity of inner discard thread 743 when is not in idle. Inner thread will not issue discards with size that 744 is smaller than granularity. The unit size is one block(4KB), now only 745 support configuring in range of [0, 512]. 746 Default: 512 747 748What: /sys/fs/f2fs/<disk>/last_age_weight 749Date: January 2023 750Contact: "Ping Xiong" <xiongping1@xiaomi.com> 751Description: When DATA SEPARATION is on, it controls the weight of last data block age. 752 753What: /sys/fs/f2fs/<disk>/compress_watermark 754Date: February 2023 755Contact: "Yangtao Li" <frank.li@vivo.com> 756Description: When compress cache is on, it controls free memory watermark 757 in order to limit caching compress page. If free memory is lower 758 than watermark, then deny caching compress page. The value should be in 759 range of (0, 100], by default it was initialized as 20(%). 760 761What: /sys/fs/f2fs/<disk>/compress_percent 762Date: February 2023 763Contact: "Yangtao Li" <frank.li@vivo.com> 764Description: When compress cache is on, it controls cached page 765 percent(compress pages / free_ram) in order to limit caching compress page. 766 If cached page percent exceed threshold, then deny caching compress page. 767 The value should be in range of (0, 100], by default it was initialized 768 as 20(%). 769 770What: /sys/fs/f2fs/<disk>/discard_io_aware 771Date: November 2023 772Contact: "Chao Yu" <chao@kernel.org> 773Description: It controls to enable/disable IO aware feature for background discard. 774 By default, the value is 1 which indicates IO aware is on. 775 776What: /sys/fs/f2fs/<disk>/blkzone_alloc_policy 777Date: July 2024 778Contact: "Yuanhong Liao" <liaoyuanhong@vivo.com> 779Description: The zone UFS we are currently using consists of two parts: 780 conventional zones and sequential zones. It can be used to control which part 781 to prioritize for writes, with a default value of 0. 782 783 ======================== ========================================= 784 value description 785 blkzone_alloc_policy = 0 Prioritize writing to sequential zones 786 blkzone_alloc_policy = 1 Only allow writing to sequential zones 787 blkzone_alloc_policy = 2 Prioritize writing to conventional zones 788 ======================== ========================================= 789 790What: /sys/fs/f2fs/<disk>/migration_window_granularity 791Date: September 2024 792Contact: "Daeho Jeong" <daehojeong@google.com> 793Description: Controls migration window granularity of garbage collection on large 794 section. it can control the scanning window granularity for GC migration 795 in a unit of segment, while migration_granularity controls the number 796 of segments which can be migrated at the same turn. 797 798What: /sys/fs/f2fs/<disk>/reserved_segments 799Date: September 2024 800Contact: "Daeho Jeong" <daehojeong@google.com> 801Description: In order to fine tune GC behavior, we can control the number of 802 reserved segments. 803 804What: /sys/fs/f2fs/<disk>/gc_no_zoned_gc_percent 805Date: September 2024 806Contact: "Daeho Jeong" <daehojeong@google.com> 807Description: If the percentage of free sections over total sections is above this 808 number, F2FS do not garbage collection for zoned devices through the 809 background GC thread. the default number is "60". 810 811What: /sys/fs/f2fs/<disk>/gc_boost_zoned_gc_percent 812Date: September 2024 813Contact: "Daeho Jeong" <daehojeong@google.com> 814Description: If the percentage of free sections over total sections is under this 815 number, F2FS boosts garbage collection for zoned devices through the 816 background GC thread. the default number is "25". 817 818What: /sys/fs/f2fs/<disk>/gc_valid_thresh_ratio 819Date: September 2024 820Contact: "Daeho Jeong" <daehojeong@google.com> 821Description: It controls the valid block ratio threshold not to trigger excessive GC 822 for zoned deivces. The initial value of it is 95(%). F2FS will stop the 823 background GC thread from intiating GC for sections having valid blocks 824 exceeding the ratio. 825 826What: /sys/fs/f2fs/<disk>/max_read_extent_count 827Date: November 2024 828Contact: "Chao Yu" <chao@kernel.org> 829Description: It controls max read extent count for per-inode, the value of threshold 830 is 10240 by default. 831