| What: /sys/fs/erofs/features/ |
| Date: November 2021 |
| Contact: "Huang Jianan" <huangjianan@oppo.com> |
| Description: Shows all enabled kernel features. |
| Supported features: |
| compr_cfgs, big_pcluster, chunked_file, device_table, |
| compr_head2, sb_chksum, ztailpacking, dedupe, fragments, |
| 48bit, metabox. |
| |
| What: /sys/fs/erofs/<disk>/sync_decompress |
| Date: November 2021 |
| Contact: "Huang Jianan" <huangjianan@oppo.com> |
| Description: Control strategy of synchronous decompression. Synchronous |
| decompression tries to decompress in the reader thread for |
| synchronous reads and small asynchronous reads (<= 12 KiB): |
| |
| - 0 (auto, default): apply to synchronous reads only, but will |
| switch to 1 (force on) if any decompression |
| request is detected in atomic contexts; |
| - 1 (force on): apply to synchronous reads and small |
| asynchronous reads; |
| - 2 (force off): disable synchronous decompression completely. |
| |
| What: /sys/fs/erofs/<disk>/drop_caches |
| Date: November 2024 |
| Contact: "Guo Chunhai" <guochunhai@vivo.com> |
| Description: Writing to this will drop compression-related caches, |
| currently used to drop in-memory pclusters and cached |
| compressed folios: |
| |
| - 1 : invalidate cached compressed folios |
| - 2 : drop in-memory pclusters |
| - 3 : drop in-memory pclusters and cached compressed folios |
| |
| What: /sys/fs/erofs/accel |
| Date: May 2025 |
| Contact: "Bo Liu" <liubo03@inspur.com> |
| Description: Used to set or show hardware accelerators in effect |
| and multiple accelerators are separated by '\n'. |
| Supported accelerator(s): qat_deflate. |
| Disable all accelerators with an empty string (echo > accel). |
| |
| What: /sys/fs/erofs/<disk>/dir_ra_bytes |
| Date: July 2025 |
| Contact: "Chao Yu" <chao@kernel.org> |
| Description: Used to set or show readahead bytes during readdir(), by |
| default the value is 16384. |
| |
| - 0: disable readahead. |
