Hi folks,
The current 32-bit block addressing limits EROFS to a 16TiB maximum
volume size with 4KiB blocks. However, several new use cases now
require larger capacity support:
- Massive datasets for model training to boost random sampling
performance for each epoch;
- Object storage clients using EROFS direct passthrough.
This extends core on-disk structures to support 48-bit block addressing,
such as inodes, device slots, and inode chunks.
In addition, it introduces an mtime field to 32-byte compact inodes for
basic timestamp support, as well as expands the superblock root NID to
an 8-byte rootnid_8b for out-of-place update incremental builds.
In order to support larger images beyond 32-bit block addressing and
efficient indexing of large compression units for compressed data, and
to better support popular compression algorithms (mainly Zstd) that
still lack native fixed-sized output compression support, introduce
byte-oriented encoded extents, so that these compressors are allowed
to retain their current methods.
Therefore, it speeds up Zstd image building a lot by using:
Processor: Intel(R) Xeon(R) Platinum 8163 CPU @ 2.50GHz * 96
Dataset: enwik9
Build time Size Type Command Line
3m52.339s 266653696 FO -C524288 -zzstd,22
3m48.549s 266174464 FO -E48bit -C524288 -zzstd,22
0m12.821s 272134144 FI -E48bit -C1048576 --max-extent-bytes=1048576 -zzstd,22
It has been stress-tested on my local setup for a while without any
strange happens.
Thanks,
Gao Xiang
Gao Xiang (10):
erofs: get rid of erofs_map_blocks_flatmode()
erofs: simplify erofs_{read,fill}_inode()
erofs: add 48-bit block addressing on-disk support
erofs: implement 48-bit block addressing for unencoded inodes
erofs: support dot-omitted directories
erofs: initialize decompression early
erofs: add encoded extent on-disk definition
erofs: implement encoded extent metadata
erofs: support unaligned encoded data
erofs: enable 48-bit layout support
fs/erofs/Kconfig | 14 +--
fs/erofs/data.c | 133 +++++++++++-------------
fs/erofs/decompressor.c | 2 +-
fs/erofs/dir.c | 7 +-
fs/erofs/erofs_fs.h | 191 ++++++++++++++++-------------------
fs/erofs/inode.c | 126 +++++++++++------------
fs/erofs/internal.h | 30 +++---
fs/erofs/super.c | 49 ++++-----
fs/erofs/sysfs.c | 2 +
fs/erofs/zdata.c | 96 +++++++++---------
fs/erofs/zmap.c | 166 +++++++++++++++++++++++++-----
include/trace/events/erofs.h | 2 +-
12 files changed, 455 insertions(+), 363 deletions(-)
--
2.43.5
