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diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs new file mode 100644 index 000000000..483639fb7 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-fs-f2fs @@ -0,0 +1,636 @@ +What: /sys/fs/f2fs/<disk>/gc_max_sleep_time +Date: July 2013 +Contact: "Namjae Jeon" <namjae.jeon@samsung.com> +Description: Controls the maximum sleep time for gc_thread. Time + is in milliseconds. + +What: /sys/fs/f2fs/<disk>/gc_min_sleep_time +Date: July 2013 +Contact: "Namjae Jeon" <namjae.jeon@samsung.com> +Description: Controls the minimum sleep time for gc_thread. Time + is in milliseconds. + +What: /sys/fs/f2fs/<disk>/gc_no_gc_sleep_time +Date: July 2013 +Contact: "Namjae Jeon" <namjae.jeon@samsung.com> +Description: Controls the default sleep time for gc_thread. Time + is in milliseconds. + +What: /sys/fs/f2fs/<disk>/gc_idle +Date: July 2013 +Contact: "Namjae Jeon" <namjae.jeon@samsung.com> +Description: Controls the victim selection policy for garbage collection. + Setting gc_idle = 0(default) will disable this option. Setting: + + =========== =============================================== + gc_idle = 1 will select the Cost Benefit approach & setting + gc_idle = 2 will select the greedy approach & setting + gc_idle = 3 will select the age-threshold based approach. + =========== =============================================== + +What: /sys/fs/f2fs/<disk>/reclaim_segments +Date: October 2013 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: This parameter controls the number of prefree segments to be + reclaimed. If the number of prefree segments is larger than + the number of segments in the proportion to the percentage + over total volume size, f2fs tries to conduct checkpoint to + reclaim the prefree segments to free segments. + By default, 5% over total # of segments. + +What: /sys/fs/f2fs/<disk>/main_blkaddr +Date: November 2019 +Contact: "Ramon Pantin" <pantin@google.com> +Description: Shows first block address of MAIN area. + +What: /sys/fs/f2fs/<disk>/ipu_policy +Date: November 2013 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the in-place-update policy. + updates in f2fs. User can set: + + ==== ================= + 0x01 F2FS_IPU_FORCE + 0x02 F2FS_IPU_SSR + 0x04 F2FS_IPU_UTIL + 0x08 F2FS_IPU_SSR_UTIL + 0x10 F2FS_IPU_FSYNC + 0x20 F2FS_IPU_ASYNC + 0x40 F2FS_IPU_NOCACHE + 0x80 F2FS_IPU_HONOR_OPU_WRITE + ==== ================= + + Refer segment.h for details. + +What: /sys/fs/f2fs/<disk>/min_ipu_util +Date: November 2013 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the FS utilization condition for the in-place-update + policies. It is used by F2FS_IPU_UTIL and F2FS_IPU_SSR_UTIL policies. + +What: /sys/fs/f2fs/<disk>/min_fsync_blocks +Date: September 2014 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the dirty page count condition for the in-place-update + policies. + +What: /sys/fs/f2fs/<disk>/min_seq_blocks +Date: August 2018 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the dirty page count condition for batched sequential + writes in writepages. + +What: /sys/fs/f2fs/<disk>/min_hot_blocks +Date: March 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the dirty page count condition for redefining hot data. + +What: /sys/fs/f2fs/<disk>/min_ssr_sections +Date: October 2017 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Controls the free section threshold to trigger SSR allocation. + If this is large, SSR mode will be enabled early. + +What: /sys/fs/f2fs/<disk>/max_small_discards +Date: November 2013 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the issue rate of discard commands that consist of small + blocks less than 2MB. The candidates to be discarded are cached until + checkpoint is triggered, and issued during the checkpoint. + By default, it is disabled with 0. + +What: /sys/fs/f2fs/<disk>/max_discard_request +Date: December 2021 +Contact: "Konstantin Vyshetsky" <vkon@google.com> +Description: Controls the number of discards a thread will issue at a time. + Higher number will allow the discard thread to finish its work + faster, at the cost of higher latency for incomming I/O. + +What: /sys/fs/f2fs/<disk>/min_discard_issue_time +Date: December 2021 +Contact: "Konstantin Vyshetsky" <vkon@google.com> +Description: Controls the interval the discard thread will wait between + issuing discard requests when there are discards to be issued and + no I/O aware interruptions occur. + +What: /sys/fs/f2fs/<disk>/mid_discard_issue_time +Date: December 2021 +Contact: "Konstantin Vyshetsky" <vkon@google.com> +Description: Controls the interval the discard thread will wait between + issuing discard requests when there are discards to be issued and + an I/O aware interruption occurs. + +What: /sys/fs/f2fs/<disk>/max_discard_issue_time +Date: December 2021 +Contact: "Konstantin Vyshetsky" <vkon@google.com> +Description: Controls the interval the discard thread will wait when there are + no discard operations to be issued. + +What: /sys/fs/f2fs/<disk>/discard_granularity +Date: July 2017 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Controls discard granularity of inner discard thread. Inner thread + will not issue discards with size that is smaller than granularity. + The unit size is one block(4KB), now only support configuring + in range of [1, 512]. Default value is 4(=16KB). + +What: /sys/fs/f2fs/<disk>/umount_discard_timeout +Date: January 2019 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Set timeout to issue discard commands during umount. + Default: 5 secs + +What: /sys/fs/f2fs/<disk>/pending_discard +Date: November 2021 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Shows the number of pending discard commands in the queue. + +What: /sys/fs/f2fs/<disk>/max_victim_search +Date: January 2014 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the number of trials to find a victim segment + when conducting SSR and cleaning operations. The default value + is 4096 which covers 8GB block address range. + +What: /sys/fs/f2fs/<disk>/migration_granularity +Date: October 2018 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Controls migration granularity of garbage collection on large + section, it can let GC move partial segment{s} of one section + in one GC cycle, so that dispersing heavy overhead GC to + multiple lightweight one. + +What: /sys/fs/f2fs/<disk>/dir_level +Date: March 2014 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the directory level for large directory. If a + directory has a number of files, it can reduce the file lookup + latency by increasing this dir_level value. Otherwise, it + needs to decrease this value to reduce the space overhead. + The default value is 0. + +What: /sys/fs/f2fs/<disk>/ram_thresh +Date: March 2014 +Contact: "Jaegeuk Kim" <jaegeuk.kim@samsung.com> +Description: Controls the memory footprint used by free nids and cached + nat entries. By default, 1 is set, which indicates + 10 MB / 1 GB RAM. + +What: /sys/fs/f2fs/<disk>/batched_trim_sections +Date: February 2015 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the trimming rate in batch mode. + <deprecated> + +What: /sys/fs/f2fs/<disk>/cp_interval +Date: October 2015 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the checkpoint timing, set to 60 seconds by default. + +What: /sys/fs/f2fs/<disk>/idle_interval +Date: January 2016 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls the idle timing of system, if there is no FS operation + during given interval. + Set to 5 seconds by default. + +What: /sys/fs/f2fs/<disk>/discard_idle_interval +Date: September 2018 +Contact: "Chao Yu" <yuchao0@huawei.com> +Contact: "Sahitya Tummala" <stummala@codeaurora.org> +Description: Controls the idle timing of discard thread given + this time interval. + Default is 5 secs. + +What: /sys/fs/f2fs/<disk>/gc_idle_interval +Date: September 2018 +Contact: "Chao Yu" <yuchao0@huawei.com> +Contact: "Sahitya Tummala" <stummala@codeaurora.org> +Description: Controls the idle timing for gc path. Set to 5 seconds by default. + +What: /sys/fs/f2fs/<disk>/iostat_enable +Date: August 2017 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Controls to enable/disable IO stat. + +What: /sys/fs/f2fs/<disk>/ra_nid_pages +Date: October 2015 +Contact: "Chao Yu" <chao2.yu@samsung.com> +Description: Controls the count of nid pages to be readaheaded. + When building free nids, F2FS reads NAT blocks ahead for + speed up. Default is 0. + +What: /sys/fs/f2fs/<disk>/dirty_nats_ratio +Date: January 2016 +Contact: "Chao Yu" <chao2.yu@samsung.com> +Description: Controls dirty nat entries ratio threshold, if current + ratio exceeds configured threshold, checkpoint will + be triggered for flushing dirty nat entries. + +What: /sys/fs/f2fs/<disk>/lifetime_write_kbytes +Date: January 2016 +Contact: "Shuoran Liu" <liushuoran@huawei.com> +Description: Shows total written kbytes issued to disk. + +What: /sys/fs/f2fs/<disk>/features +Date: July 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: <deprecated: should use /sys/fs/f2fs/<disk>/feature_list/ + Shows all enabled features in current device. + Supported features: + encryption, blkzoned, extra_attr, projquota, inode_checksum, + flexible_inline_xattr, quota_ino, inode_crtime, lost_found, + verity, sb_checksum, casefold, readonly, compression, pin_file. + +What: /sys/fs/f2fs/<disk>/feature_list/ +Date: June 2021 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Expand /sys/fs/f2fs/<disk>/features to meet sysfs rule. + Supported on-disk features: + encryption, block_zoned (aka blkzoned), extra_attr, + project_quota (aka projquota), inode_checksum, + flexible_inline_xattr, quota_ino, inode_crtime, lost_found, + verity, sb_checksum, casefold, readonly, compression. + Note that, pin_file is moved into /sys/fs/f2fs/features/. + +What: /sys/fs/f2fs/features/ +Date: July 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Shows all enabled kernel features. + Supported features: + encryption, block_zoned, extra_attr, project_quota, + inode_checksum, flexible_inline_xattr, quota_ino, + inode_crtime, lost_found, verity, sb_checksum, + casefold, readonly, compression, test_dummy_encryption_v2, + atomic_write, pin_file, encrypted_casefold. + +What: /sys/fs/f2fs/<disk>/inject_rate +Date: May 2016 +Contact: "Sheng Yong" <shengyong1@huawei.com> +Description: Controls the injection rate of arbitrary faults. + +What: /sys/fs/f2fs/<disk>/inject_type +Date: May 2016 +Contact: "Sheng Yong" <shengyong1@huawei.com> +Description: Controls the injection type of arbitrary faults. + +What: /sys/fs/f2fs/<disk>/dirty_segments +Date: October 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Shows the number of dirty segments. + +What: /sys/fs/f2fs/<disk>/reserved_blocks +Date: June 2017 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Controls target reserved blocks in system, the threshold + is soft, it could exceed current available user space. + +What: /sys/fs/f2fs/<disk>/current_reserved_blocks +Date: October 2017 +Contact: "Yunlong Song" <yunlong.song@huawei.com> +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Shows current reserved blocks in system, it may be temporarily + smaller than target_reserved_blocks, but will gradually + increase to target_reserved_blocks when more free blocks are + freed by user later. + +What: /sys/fs/f2fs/<disk>/gc_urgent +Date: August 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Do background GC aggressively when set. Set to 0 by default. + gc urgent high(1): does GC forcibly in a period of given + gc_urgent_sleep_time and ignores I/O idling check. uses greedy + GC approach and turns SSR mode on. + gc urgent low(2): lowers the bar of checking I/O idling in + order to process outstanding discard commands and GC a + little bit aggressively. uses cost benefit GC approach. + gc urgent mid(3): does GC forcibly in a period of given + gc_urgent_sleep_time and executes a mid level of I/O idling check. + uses cost benefit GC approach. + +What: /sys/fs/f2fs/<disk>/gc_urgent_sleep_time +Date: August 2017 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls sleep time of GC urgent mode. Set to 500ms by default. + +What: /sys/fs/f2fs/<disk>/readdir_ra +Date: November 2017 +Contact: "Sheng Yong" <shengyong1@huawei.com> +Description: Controls readahead inode block in readdir. Enabled by default. + +What: /sys/fs/f2fs/<disk>/gc_pin_file_thresh +Date: January 2018 +Contact: Jaegeuk Kim <jaegeuk@kernel.org> +Description: This indicates how many GC can be failed for the pinned + file. If it exceeds this, F2FS doesn't guarantee its pinning + state. 2048 trials is set by default. + +What: /sys/fs/f2fs/<disk>/extension_list +Date: Feburary 2018 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Used to control configure extension list: + - Query: cat /sys/fs/f2fs/<disk>/extension_list + - Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list + - Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list + - [h] means add/del hot file extension + - [c] means add/del cold file extension + +What: /sys/fs/f2fs/<disk>/unusable +Date April 2019 +Contact: "Daniel Rosenberg" <drosen@google.com> +Description: If checkpoint=disable, it displays the number of blocks that + are unusable. + If checkpoint=enable it displays the number of blocks that + would be unusable if checkpoint=disable were to be set. + +What: /sys/fs/f2fs/<disk>/encoding +Date July 2019 +Contact: "Daniel Rosenberg" <drosen@google.com> +Description: Displays name and version of the encoding set for the filesystem. + If no encoding is set, displays (none) + +What: /sys/fs/f2fs/<disk>/free_segments +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of free segments in disk. + +What: /sys/fs/f2fs/<disk>/cp_foreground_calls +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of checkpoint operations performed on demand. Available when + CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/cp_background_calls +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of checkpoint operations performed in the background to + free segments. Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/gc_foreground_calls +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of garbage collection operations performed on demand. + Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/gc_background_calls +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of garbage collection operations triggered in background. + Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/moved_blocks_foreground +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of blocks moved by garbage collection in foreground. + Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/moved_blocks_background +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Number of blocks moved by garbage collection in background. + Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/avg_vblocks +Date: September 2019 +Contact: "Hridya Valsaraju" <hridya@google.com> +Description: Average number of valid blocks. + Available when CONFIG_F2FS_STAT_FS=y. + +What: /sys/fs/f2fs/<disk>/mounted_time_sec +Date: February 2020 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Show the mounted time in secs of this partition. + +What: /sys/fs/f2fs/<disk>/data_io_flag +Date: April 2020 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Give a way to attach REQ_META|FUA to data writes + given temperature-based bits. Now the bits indicate: + + +-------------------+-------------------+ + | REQ_META | REQ_FUA | + +------+------+-----+------+------+-----+ + | 5 | 4 | 3 | 2 | 1 | 0 | + +------+------+-----+------+------+-----+ + | Cold | Warm | Hot | Cold | Warm | Hot | + +------+------+-----+------+------+-----+ + +What: /sys/fs/f2fs/<disk>/node_io_flag +Date: June 2020 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Give a way to attach REQ_META|FUA to node writes + given temperature-based bits. Now the bits indicate: + + +-------------------+-------------------+ + | REQ_META | REQ_FUA | + +------+------+-----+------+------+-----+ + | 5 | 4 | 3 | 2 | 1 | 0 | + +------+------+-----+------+------+-----+ + | Cold | Warm | Hot | Cold | Warm | Hot | + +------+------+-----+------+------+-----+ + +What: /sys/fs/f2fs/<disk>/iostat_period_ms +Date: April 2020 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Give a way to change iostat_period time. 3secs by default. + The new iostat trace gives stats gap given the period. +What: /sys/fs/f2fs/<disk>/max_io_bytes +Date: December 2020 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: This gives a control to limit the bio size in f2fs. + Default is zero, which will follow underlying block layer limit, + whereas, if it has a certain bytes value, f2fs won't submit a + bio larger than that size. + +What: /sys/fs/f2fs/<disk>/stat/sb_status +Date: December 2020 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: Show status of f2fs superblock in real time. + + ====== ===================== ================================= + value sb status macro description + 0x1 SBI_IS_DIRTY dirty flag for checkpoint + 0x2 SBI_IS_CLOSE specify unmounting + 0x4 SBI_NEED_FSCK need fsck.f2fs to fix + 0x8 SBI_POR_DOING recovery is doing or not + 0x10 SBI_NEED_SB_WRITE need to recover superblock + 0x20 SBI_NEED_CP need to checkpoint + 0x40 SBI_IS_SHUTDOWN shutdown by ioctl + 0x80 SBI_IS_RECOVERED recovered orphan/data + 0x100 SBI_CP_DISABLED CP was disabled last mount + 0x200 SBI_CP_DISABLED_QUICK CP was disabled quickly + 0x400 SBI_QUOTA_NEED_FLUSH need to flush quota info in CP + 0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP + 0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted + 0x2000 SBI_IS_RESIZEFS resizefs is in process + 0x4000 SBI_IS_FREEZING freefs is in process + ====== ===================== ================================= + +What: /sys/fs/f2fs/<disk>/stat/cp_status +Date: September 2022 +Contact: "Chao Yu" <chao.yu@oppo.com> +Description: Show status of f2fs checkpoint in real time. + + =============================== ============================== + cp flag value + CP_UMOUNT_FLAG 0x00000001 + CP_ORPHAN_PRESENT_FLAG 0x00000002 + CP_COMPACT_SUM_FLAG 0x00000004 + CP_ERROR_FLAG 0x00000008 + CP_FSCK_FLAG 0x00000010 + CP_FASTBOOT_FLAG 0x00000020 + CP_CRC_RECOVERY_FLAG 0x00000040 + CP_NAT_BITS_FLAG 0x00000080 + CP_TRIMMED_FLAG 0x00000100 + CP_NOCRC_RECOVERY_FLAG 0x00000200 + CP_LARGE_NAT_BITMAP_FLAG 0x00000400 + CP_QUOTA_NEED_FSCK_FLAG 0x00000800 + CP_DISABLED_FLAG 0x00001000 + CP_DISABLED_QUICK_FLAG 0x00002000 + CP_RESIZEFS_FLAG 0x00004000 + =============================== ============================== + +What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio +Date: January 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Give a way to change checkpoint merge daemon's io priority. + Its default value is "be,3", which means "BE" I/O class and + I/O priority "3". We can select the class between "rt" and "be", + and set the I/O priority within valid range of it. "," delimiter + is necessary in between I/O class and priority number. + +What: /sys/fs/f2fs/<disk>/ovp_segments +Date: March 2021 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Shows the number of overprovision segments. + +What: /sys/fs/f2fs/<disk>/compr_written_block +Date: March 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the block count written after compression since mount. Note + that when the compressed blocks are deleted, this count doesn't + decrease. If you write "0" here, you can initialize + compr_written_block and compr_saved_block to "0". + +What: /sys/fs/f2fs/<disk>/compr_saved_block +Date: March 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the saved block count with compression since mount. Note + that when the compressed blocks are deleted, this count doesn't + decrease. If you write "0" here, you can initialize + compr_written_block and compr_saved_block to "0". + +What: /sys/fs/f2fs/<disk>/compr_new_inode +Date: March 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the count of inode newly enabled for compression since mount. + Note that when the compression is disabled for the files, this count + doesn't decrease. If you write "0" here, you can initialize + compr_new_inode to "0". + +What: /sys/fs/f2fs/<disk>/atgc_candidate_ratio +Date: May 2021 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: When ATGC is on, it controls candidate ratio in order to limit total + number of potential victim in all candidates, the value should be in + range of [0, 100], by default it was initialized as 20(%). + +What: /sys/fs/f2fs/<disk>/atgc_candidate_count +Date: May 2021 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: When ATGC is on, it controls candidate count in order to limit total + number of potential victim in all candidates, by default it was + initialized as 10 (sections). + +What: /sys/fs/f2fs/<disk>/atgc_age_weight +Date: May 2021 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: When ATGC is on, it controls age weight to balance weight proportion + in between aging and valid blocks, the value should be in range of + [0, 100], by default it was initialized as 60(%). + +What: /sys/fs/f2fs/<disk>/atgc_age_threshold +Date: May 2021 +Contact: "Chao Yu" <yuchao0@huawei.com> +Description: When ATGC is on, it controls age threshold to bypass GCing young + candidates whose age is not beyond the threshold, by default it was + initialized as 604800 seconds (equals to 7 days). + +What: /sys/fs/f2fs/<disk>/gc_reclaimed_segments +Date: July 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show how many segments have been reclaimed by GC during a specific + GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy, + 3: GC idle AT, 4: GC urgent high, 5: GC urgent low 6: GC urgent mid) + You can re-initialize this value to "0". + +What: /sys/fs/f2fs/<disk>/gc_segment_mode +Date: July 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. + Refer to the description of the modes in "gc_reclaimed_segments". + +What: /sys/fs/f2fs/<disk>/seq_file_ra_mul +Date: July 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: You can control the multiplier value of bdi device readahead window size + between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. + +What: /sys/fs/f2fs/<disk>/max_fragment_chunk +Date: August 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: With "mode=fragment:block" mount options, we can scatter block allocation. + f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole + in the length of 1..<max_fragment_hole> by turns. This value can be set + between 1..512 and the default value is 4. + +What: /sys/fs/f2fs/<disk>/max_fragment_hole +Date: August 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: With "mode=fragment:block" mount options, we can scatter block allocation. + f2fs will allocate 1..<max_fragment_chunk> blocks in a chunk and make a hole + in the length of 1..<max_fragment_hole> by turns. This value can be set + between 1..512 and the default value is 4. + +What: /sys/fs/f2fs/<disk>/gc_urgent_high_remaining +Date: December 2021 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: You can set the trial count limit for GC urgent high mode with this value. + If GC thread gets to the limit, the mode will turn back to GC normal mode. + By default, the value is zero, which means there is no limit like before. + +What: /sys/fs/f2fs/<disk>/max_roll_forward_node_blocks +Date: January 2022 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Controls max # of node block writes to be used for roll forward + recovery. This can limit the roll forward recovery time. + +What: /sys/fs/f2fs/<disk>/unusable_blocks_per_sec +Date: June 2022 +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org> +Description: Shows the number of unusable blocks in a section which was defined by + the zone capacity reported by underlying zoned device. + +What: /sys/fs/f2fs/<disk>/current_atomic_write +Date: July 2022 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the total current atomic write block count, which is not committed yet. + This is a read-only entry. + +What: /sys/fs/f2fs/<disk>/peak_atomic_write +Date: July 2022 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the peak value of total current atomic write block count after boot. + If you write "0" here, you can initialize to "0". + +What: /sys/fs/f2fs/<disk>/committed_atomic_block +Date: July 2022 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the accumulated total committed atomic write block count after boot. + If you write "0" here, you can initialize to "0". + +What: /sys/fs/f2fs/<disk>/revoked_atomic_block +Date: July 2022 +Contact: "Daeho Jeong" <daehojeong@google.com> +Description: Show the accumulated total revoked atomic write block count after boot. + If you write "0" here, you can initialize to "0". |