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. uses cost benefit GC approach. 315 gc urgent mid(3): does GC forcibly in a period of given 316 gc_urgent_sleep_time and executes a mid level of I/O idling check. 317 uses cost benefit GC approach. 318 319What: /sys/fs/f2fs/<disk>/gc_urgent_sleep_time 320Date: August 2017 321Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 322Description: Controls sleep time of GC urgent mode. Set to 500ms by default. 323 324What: /sys/fs/f2fs/<disk>/readdir_ra 325Date: November 2017 326Contact: "Sheng Yong" <shengyong1@huawei.com> 327Description: Controls readahead inode block in readdir. Enabled by default. 328 329What: /sys/fs/f2fs/<disk>/gc_pin_file_thresh 330Date: January 2018 331Contact: Jaegeuk Kim <jaegeuk@kernel.org> 332Description: This indicates how many GC can be failed for the pinned 333 file. If it exceeds this, F2FS doesn't guarantee its pinning 334 state. 2048 trials is set by default, and 65535 as maximum. 335 336What: /sys/fs/f2fs/<disk>/extension_list 337Date: February 2018 338Contact: "Chao Yu" <yuchao0@huawei.com> 339Description: Used to control configure extension list: 340 - Query: cat /sys/fs/f2fs/<disk>/extension_list 341 - Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list 342 - Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list 343 - [h] means add/del hot file extension 344 - [c] means add/del cold file extension 345 346What: /sys/fs/f2fs/<disk>/unusable 347Date April 2019 348Contact: "Daniel Rosenberg" <drosen@google.com> 349Description: If checkpoint=disable, it displays the number of blocks that 350 are unusable. 351 If checkpoint=enable it displays the number of blocks that 352 would be unusable if checkpoint=disable were to be set. 353 354What: /sys/fs/f2fs/<disk>/encoding 355Date July 2019 356Contact: "Daniel Rosenberg" <drosen@google.com> 357Description: Displays name and version of the encoding set for the filesystem. 358 If no encoding is set, displays (none) 359 360What: /sys/fs/f2fs/<disk>/free_segments 361Date: September 2019 362Contact: "Hridya Valsaraju" <hridya@google.com> 363Description: Number of free segments in disk. 364 365What: /sys/fs/f2fs/<disk>/cp_foreground_calls 366Date: September 2019 367Contact: "Hridya Valsaraju" <hridya@google.com> 368Description: Number of checkpoint operations performed on demand. Available when 369 CONFIG_F2FS_STAT_FS=y. 370 371What: /sys/fs/f2fs/<disk>/cp_background_calls 372Date: September 2019 373Contact: "Hridya Valsaraju" <hridya@google.com> 374Description: Number of checkpoint operations performed in the background to 375 free segments. Available when CONFIG_F2FS_STAT_FS=y. 376 377What: /sys/fs/f2fs/<disk>/gc_foreground_calls 378Date: September 2019 379Contact: "Hridya Valsaraju" <hridya@google.com> 380Description: Number of garbage collection operations performed on demand. 381 Available when CONFIG_F2FS_STAT_FS=y. 382 383What: /sys/fs/f2fs/<disk>/gc_background_calls 384Date: September 2019 385Contact: "Hridya Valsaraju" <hridya@google.com> 386Description: Number of garbage collection operations triggered in background. 387 Available when CONFIG_F2FS_STAT_FS=y. 388 389What: /sys/fs/f2fs/<disk>/moved_blocks_foreground 390Date: September 2019 391Contact: "Hridya Valsaraju" <hridya@google.com> 392Description: Number of blocks moved by garbage collection in foreground. 393 Available when CONFIG_F2FS_STAT_FS=y. 394 395What: /sys/fs/f2fs/<disk>/moved_blocks_background 396Date: September 2019 397Contact: "Hridya Valsaraju" <hridya@google.com> 398Description: Number of blocks moved by garbage collection in background. 399 Available when CONFIG_F2FS_STAT_FS=y. 400 401What: /sys/fs/f2fs/<disk>/avg_vblocks 402Date: September 2019 403Contact: "Hridya Valsaraju" <hridya@google.com> 404Description: Average number of valid blocks. 405 Available when CONFIG_F2FS_STAT_FS=y. 406 407What: /sys/fs/f2fs/<disk>/mounted_time_sec 408Date: February 2020 409Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 410Description: Show the mounted time in secs of this partition. 411 412What: /sys/fs/f2fs/<disk>/data_io_flag 413Date: April 2020 414Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 415Description: Give a way to attach REQ_META|FUA to data writes 416 given temperature-based bits. Now the bits indicate: 417 418 +-------------------+-------------------+ 419 | REQ_META | REQ_FUA | 420 +------+------+-----+------+------+-----+ 421 | 5 | 4 | 3 | 2 | 1 | 0 | 422 +------+------+-----+------+------+-----+ 423 | Cold | Warm | Hot | Cold | Warm | Hot | 424 +------+------+-----+------+------+-----+ 425 426What: /sys/fs/f2fs/<disk>/node_io_flag 427Date: June 2020 428Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 429Description: Give a way to attach REQ_META|FUA to node writes 430 given temperature-based bits. Now the bits indicate: 431 432 +-------------------+-------------------+ 433 | REQ_META | REQ_FUA | 434 +------+------+-----+------+------+-----+ 435 | 5 | 4 | 3 | 2 | 1 | 0 | 436 +------+------+-----+------+------+-----+ 437 | Cold | Warm | Hot | Cold | Warm | Hot | 438 +------+------+-----+------+------+-----+ 439 440What: /sys/fs/f2fs/<disk>/iostat_period_ms 441Date: April 2020 442Contact: "Daeho Jeong" <daehojeong@google.com> 443Description: Give a way to change iostat_period time. 3secs by default. 444 The new iostat trace gives stats gap given the period. 445What: /sys/fs/f2fs/<disk>/max_io_bytes 446Date: December 2020 447Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 448Description: This gives a control to limit the bio size in f2fs. 449 Default is zero, which will follow underlying block layer limit, 450 whereas, if it has a certain bytes value, f2fs won't submit a 451 bio larger than that size. 452 453What: /sys/fs/f2fs/<disk>/stat/sb_status 454Date: December 2020 455Contact: "Chao Yu" <yuchao0@huawei.com> 456Description: Show status of f2fs superblock in real time. 457 458 ====== ===================== ================================= 459 value sb status macro description 460 0x1 SBI_IS_DIRTY dirty flag for checkpoint 461 0x2 SBI_IS_CLOSE specify unmounting 462 0x4 SBI_NEED_FSCK need fsck.f2fs to fix 463 0x8 SBI_POR_DOING recovery is doing or not 464 0x10 SBI_NEED_SB_WRITE need to recover superblock 465 0x20 SBI_NEED_CP need to checkpoint 466 0x40 SBI_IS_SHUTDOWN shutdown by ioctl 467 0x80 SBI_IS_RECOVERED recovered orphan/data 468 0x100 SBI_CP_DISABLED CP was disabled last mount 469 0x200 SBI_CP_DISABLED_QUICK CP was disabled quickly 470 0x400 SBI_QUOTA_NEED_FLUSH need to flush quota info in CP 471 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP 472 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted 473 0x2000 SBI_IS_RESIZEFS resizefs is in process 474 0x4000 SBI_IS_FREEZING freefs is in process 475 ====== ===================== ================================= 476 477What: /sys/fs/f2fs/<disk>/stat/cp_status 478Date: September 2022 479Contact: "Chao Yu" <chao.yu@oppo.com> 480Description: Show status of f2fs checkpoint in real time. 481 482 =============================== ============================== 483 cp flag value 484 CP_UMOUNT_FLAG 0x00000001 485 CP_ORPHAN_PRESENT_FLAG 0x00000002 486 CP_COMPACT_SUM_FLAG 0x00000004 487 CP_ERROR_FLAG 0x00000008 488 CP_FSCK_FLAG 0x00000010 489 CP_FASTBOOT_FLAG 0x00000020 490 CP_CRC_RECOVERY_FLAG 0x00000040 491 CP_NAT_BITS_FLAG 0x00000080 492 CP_TRIMMED_FLAG 0x00000100 493 CP_NOCRC_RECOVERY_FLAG 0x00000200 494 CP_LARGE_NAT_BITMAP_FLAG 0x00000400 495 CP_QUOTA_NEED_FSCK_FLAG 0x00000800 496 CP_DISABLED_FLAG 0x00001000 497 CP_DISABLED_QUICK_FLAG 0x00002000 498 CP_RESIZEFS_FLAG 0x00004000 499 =============================== ============================== 500 501What: /sys/fs/f2fs/<disk>/stat/issued_discard 502Date: December 2023 503Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 504Description: Shows the number of issued discard. 505 506What: /sys/fs/f2fs/<disk>/stat/queued_discard 507Date: December 2023 508Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 509Description: Shows the number of queued discard. 510 511What: /sys/fs/f2fs/<disk>/stat/undiscard_blks 512Date: December 2023 513Contact: "Zhiguo Niu" <zhiguo.niu@unisoc.com> 514Description: Shows the total number of undiscard blocks. 515 516What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio 517Date: January 2021 518Contact: "Daeho Jeong" <daehojeong@google.com> 519Description: Give a way to change checkpoint merge daemon's io priority. 520 Its default value is "be,3", which means "BE" I/O class and 521 I/O priority "3". We can select the class between "rt" and "be", 522 and set the I/O priority within valid range of it. "," delimiter 523 is necessary in between I/O class and priority number. 524 525What: /sys/fs/f2fs/<disk>/ovp_segments 526Date: March 2021 527Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 528Description: Shows the number of overprovision segments. 529 530What: /sys/fs/f2fs/<disk>/compr_written_block 531Date: March 2021 532Contact: "Daeho Jeong" <daehojeong@google.com> 533Description: Show the block count written after compression since mount. Note 534 that when the compressed blocks are deleted, this count doesn't 535 decrease. If you write "0" here, you can initialize 536 compr_written_block and compr_saved_block to "0". 537 538What: /sys/fs/f2fs/<disk>/compr_saved_block 539Date: March 2021 540Contact: "Daeho Jeong" <daehojeong@google.com> 541Description: Show the saved block count with compression since mount. Note 542 that when the compressed blocks are deleted, this count doesn't 543 decrease. If you write "0" here, you can initialize 544 compr_written_block and compr_saved_block to "0". 545 546What: /sys/fs/f2fs/<disk>/compr_new_inode 547Date: March 2021 548Contact: "Daeho Jeong" <daehojeong@google.com> 549Description: Show the count of inode newly enabled for compression since mount. 550 Note that when the compression is disabled for the files, this count 551 doesn't decrease. If you write "0" here, you can initialize 552 compr_new_inode to "0". 553 554What: /sys/fs/f2fs/<disk>/atgc_candidate_ratio 555Date: May 2021 556Contact: "Chao Yu" <yuchao0@huawei.com> 557Description: When ATGC is on, it controls candidate ratio in order to limit total 558 number of potential victim in all candidates, the value should be in 559 range of [0, 100], by default it was initialized as 20(%). 560 561What: /sys/fs/f2fs/<disk>/atgc_candidate_count 562Date: May 2021 563Contact: "Chao Yu" <yuchao0@huawei.com> 564Description: When ATGC is on, it controls candidate count in order to limit total 565 number of potential victim in all candidates, by default it was 566 initialized as 10 (sections). 567 568What: /sys/fs/f2fs/<disk>/atgc_age_weight 569Date: May 2021 570Contact: "Chao Yu" <yuchao0@huawei.com> 571Description: When ATGC is on, it controls age weight to balance weight proportion 572 in between aging and valid blocks, the value should be in range of 573 [0, 100], by default it was initialized as 60(%). 574 575What: /sys/fs/f2fs/<disk>/atgc_age_threshold 576Date: May 2021 577Contact: "Chao Yu" <yuchao0@huawei.com> 578Description: When ATGC is on, it controls age threshold to bypass GCing young 579 candidates whose age is not beyond the threshold, by default it was 580 initialized as 604800 seconds (equals to 7 days). 581 582What: /sys/fs/f2fs/<disk>/atgc_enabled 583Date: Feb 2024 584Contact: "Jinbao Liu" <liujinbao1@xiaomi.com> 585Description: It represents whether ATGC is on or off. The value is 1 which 586 indicates that ATGC is on, and 0 indicates that it is off. 587 588What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments 589Date: July 2021 590Contact: "Daeho Jeong" <daehojeong@google.com> 591Description: Show how many segments have been reclaimed by GC during a specific 592 GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy, 593 3: GC idle AT, 4: GC urgent high, 5: GC urgent low 6: GC urgent mid) 594 You can re-initialize this value to "0". 595 596What: /sys/fs/f2fs/<disk>/gc_segment_mode 597Date: July 2021 598Contact: "Daeho Jeong" <daehojeong@google.com> 599Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. 600 Refer to the description of the modes in "gc_reclaimed_segments". 601 602What: /sys/fs/f2fs/<disk>/seq_file_ra_mul 603Date: July 2021 604Contact: "Daeho Jeong" <daehojeong@google.com> 605Description: You can control the multiplier value of bdi device readahead window size 606 between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. 607 608What: /sys/fs/f2fs/<disk>/max_fragment_chunk 609Date: August 2021 610Contact: "Daeho Jeong" <daehojeong@google.com> 611Description: With "mode=fragment:block" mount options, we can scatter block allocation. 612 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole 613 in the length of 1..<max_fragment_hole> by turns. This value can be set 614 between 1..512 and the default value is 4. 615 616What: /sys/fs/f2fs/<disk>/max_fragment_hole 617Date: August 2021 618Contact: "Daeho Jeong" <daehojeong@google.com> 619Description: With "mode=fragment:block" mount options, we can scatter block allocation. 620 f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole 621 in the length of 1..<max_fragment_hole> by turns. This value can be set 622 between 1..512 and the default value is 4. 623 624What: /sys/fs/f2fs/<disk>/gc_remaining_trials 625Date: October 2022 626Contact: "Yangtao Li" <frank.li@vivo.com> 627Description: You can set the trial count limit for GC urgent and idle mode with this value. 628 If GC thread gets to the limit, the mode will turn back to GC normal mode. 629 By default, the value is zero, which means there is no limit like before. 630 631What: /sys/fs/f2fs/<disk>/max_roll_forward_node_blocks 632Date: January 2022 633Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 634Description: Controls max # of node block writes to be used for roll forward 635 recovery. This can limit the roll forward recovery time. 636 637What: /sys/fs/f2fs/<disk>/unusable_blocks_per_sec 638Date: June 2022 639Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> 640Description: Shows the number of unusable blocks in a section which was defined by 641 the zone capacity reported by underlying zoned device. 642 643What: /sys/fs/f2fs/<disk>/current_atomic_write 644Date: July 2022 645Contact: "Daeho Jeong" <daehojeong@google.com> 646Description: Show the total current atomic write block count, which is not committed yet. 647 This is a read-only entry. 648 649What: /sys/fs/f2fs/<disk>/peak_atomic_write 650Date: July 2022 651Contact: "Daeho Jeong" <daehojeong@google.com> 652Description: Show the peak value of total current atomic write block count after boot. 653 If you write "0" here, you can initialize to "0". 654 655What: /sys/fs/f2fs/<disk>/committed_atomic_block 656Date: July 2022 657Contact: "Daeho Jeong" <daehojeong@google.com> 658Description: Show the accumulated total committed atomic write block count after boot. 659 If you write "0" here, you can initialize to "0". 660 661What: /sys/fs/f2fs/<disk>/revoked_atomic_block 662Date: July 2022 663Contact: "Daeho Jeong" <daehojeong@google.com> 664Description: Show the accumulated total revoked atomic write block count after boot. 665 If you write "0" here, you can initialize to "0". 666 667What: /sys/fs/f2fs/<disk>/gc_mode 668Date: October 2022 669Contact: "Yangtao Li" <frank.li@vivo.com> 670Description: Show the current gc_mode as a string. 671 This is a read-only entry. 672 673What: /sys/fs/f2fs/<disk>/discard_urgent_util 674Date: November 2022 675Contact: "Yangtao Li" <frank.li@vivo.com> 676Description: When space utilization exceeds this, do background DISCARD aggressively. 677 Does DISCARD forcibly in a period of given min_discard_issue_time when the number 678 of discards is not 0 and set discard granularity to 1. 679 Default: 80 680 681What: /sys/fs/f2fs/<disk>/hot_data_age_threshold 682Date: November 2022 683Contact: "Ping Xiong" <xiongping1@xiaomi.com> 684Description: When DATA SEPARATION is on, it controls the age threshold to indicate 685 the data blocks as hot. By default it was initialized as 262144 blocks 686 (equals to 1GB). 687 688What: /sys/fs/f2fs/<disk>/warm_data_age_threshold 689Date: November 2022 690Contact: "Ping Xiong" <xiongping1@xiaomi.com> 691Description: When DATA SEPARATION is on, it controls the age threshold to indicate 692 the data blocks as warm. By default it was initialized as 2621440 blocks 693 (equals to 10GB). 694 695What: /sys/fs/f2fs/<disk>/fault_rate 696Date: May 2016 697Contact: "Sheng Yong" <shengyong@oppo.com> 698Contact: "Chao Yu" <chao@kernel.org> 699Description: Enable fault injection in all supported types with 700 specified injection rate. 701 702What: /sys/fs/f2fs/<disk>/fault_type 703Date: May 2016 704Contact: "Sheng Yong" <shengyong@oppo.com> 705Contact: "Chao Yu" <chao@kernel.org> 706Description: Support configuring fault injection type, should be 707 enabled with fault_injection option, fault type value 708 is shown below, it supports single or combined type. 709 710 =========================== =========== 711 Type_Name Type_Value 712 =========================== =========== 713 FAULT_KMALLOC 0x000000001 714 FAULT_KVMALLOC 0x000000002 715 FAULT_PAGE_ALLOC 0x000000004 716 FAULT_PAGE_GET 0x000000008 717 FAULT_ALLOC_BIO 0x000000010 (obsolete) 718 FAULT_ALLOC_NID 0x000000020 719 FAULT_ORPHAN 0x000000040 720 FAULT_BLOCK 0x000000080 721 FAULT_DIR_DEPTH 0x000000100 722 FAULT_EVICT_INODE 0x000000200 723 FAULT_TRUNCATE 0x000000400 724 FAULT_READ_IO 0x000000800 725 FAULT_CHECKPOINT 0x000001000 726 FAULT_DISCARD 0x000002000 727 FAULT_WRITE_IO 0x000004000 728 FAULT_SLAB_ALLOC 0x000008000 729 FAULT_DQUOT_INIT 0x000010000 730 FAULT_LOCK_OP 0x000020000 731 FAULT_BLKADDR_VALIDITY 0x000040000 732 FAULT_BLKADDR_CONSISTENCE 0x000080000 733 FAULT_NO_SEGMENT 0x000100000 734 =========================== =========== 735 736What: /sys/fs/f2fs/<disk>/discard_io_aware_gran 737Date: January 2023 738Contact: "Yangtao Li" <frank.li@vivo.com> 739Description: Controls background discard granularity of inner discard thread 740 when is not in idle. Inner thread will not issue discards with size that 741 is smaller than granularity. The unit size is one block(4KB), now only 742 support configuring in range of [0, 512]. 743 Default: 512 744 745What: /sys/fs/f2fs/<disk>/last_age_weight 746Date: January 2023 747Contact: "Ping Xiong" <xiongping1@xiaomi.com> 748Description: When DATA SEPARATION is on, it controls the weight of last data block age. 749 750What: /sys/fs/f2fs/<disk>/compress_watermark 751Date: February 2023 752Contact: "Yangtao Li" <frank.li@vivo.com> 753Description: When compress cache is on, it controls free memory watermark 754 in order to limit caching compress page. If free memory is lower 755 than watermark, then deny caching compress page. The value should be in 756 range of (0, 100], by default it was initialized as 20(%). 757 758What: /sys/fs/f2fs/<disk>/compress_percent 759Date: February 2023 760Contact: "Yangtao Li" <frank.li@vivo.com> 761Description: When compress cache is on, it controls cached page 762 percent(compress pages / free_ram) in order to limit caching compress page. 763 If cached page percent exceed threshold, then deny caching compress page. 764 The value should be in range of (0, 100], by default it was initialized 765 as 20(%). 766 767What: /sys/fs/f2fs/<disk>/discard_io_aware 768Date: November 2023 769Contact: "Chao Yu" <chao@kernel.org> 770Description: It controls to enable/disable IO aware feature for background discard. 771 By default, the value is 1 which indicates IO aware is on. 772 773What: /sys/fs/f2fs/<disk>/blkzone_alloc_policy 774Date: July 2024 775Contact: "Yuanhong Liao" <liaoyuanhong@vivo.com> 776Description: The zone UFS we are currently using consists of two parts: 777 conventional zones and sequential zones. It can be used to control which part 778 to prioritize for writes, with a default value of 0. 779 780 ======================== ========================================= 781 value description 782 blkzone_alloc_policy = 0 Prioritize writing to sequential zones 783 blkzone_alloc_policy = 1 Only allow writing to sequential zones 784 blkzone_alloc_policy = 2 Prioritize writing to conventional zones 785 ======================== ========================================= 786 787What: /sys/fs/f2fs/<disk>/migration_window_granularity 788Date: September 2024 789Contact: "Daeho Jeong" <daehojeong@google.com> 790Description: Controls migration window granularity of garbage collection on large 791 section. it can control the scanning window granularity for GC migration 792 in a unit of segment, while migration_granularity controls the number 793 of segments which can be migrated at the same turn. 794 795What: /sys/fs/f2fs/<disk>/reserved_segments 796Date: September 2024 797Contact: "Daeho Jeong" <daehojeong@google.com> 798Description: In order to fine tune GC behavior, we can control the number of 799 reserved segments. 800 801What: /sys/fs/f2fs/<disk>/gc_no_zoned_gc_percent 802Date: September 2024 803Contact: "Daeho Jeong" <daehojeong@google.com> 804Description: If the percentage of free sections over total sections is above this 805 number, F2FS do not garbage collection for zoned devices through the 806 background GC thread. the default number is "60". 807 808What: /sys/fs/f2fs/<disk>/gc_boost_zoned_gc_percent 809Date: September 2024 810Contact: "Daeho Jeong" <daehojeong@google.com> 811Description: If the percentage of free sections over total sections is under this 812 number, F2FS boosts garbage collection for zoned devices through the 813 background GC thread. the default number is "25". 814 815What: /sys/fs/f2fs/<disk>/gc_valid_thresh_ratio 816Date: September 2024 817Contact: "Daeho Jeong" <daehojeong@google.com> 818Description: It controls the valid block ratio threshold not to trigger excessive GC 819 for zoned deivces. The initial value of it is 95(%). F2FS will stop the 820 background GC thread from intiating GC for sections having valid blocks 821 exceeding the ratio. 822