On 2024/6/25 20:15, Sheng Yong wrote:
When new_curseg() is allocating a new segment, if mode=fragment:xxx is switched on in large section scenario, __get_next_segno() will select the next segno randomly in the range of [0, maxsegno] in order to fragment segments.If the candidate segno is free, get_new_segment() will use it directly as the new segment. However, if the section of the candidate is not empty, and some other segments have already been used, and have a different type (e.g NODE) with the candidate (e.g DATA), GC will complain inconsistent segment type later. This could be reproduced by the following steps: dd if=/dev/zero of=test.img bs=1M count=10240 mkfs.f2fs -s 128 test.img mount -t f2fs test.img /mnt -o mode=fragment:block echo 1 > /sys/fs/f2fs/loop0/max_fragment_chunk echo 512 > /sys/fs/f2fs/loop0/max_fragment_hole dd if=/dev/zero of=/mnt/testfile bs=4K count=100 umount /mnt F2FS-fs (loop0): Inconsistent segment (4377) type [0, 1] in SSA and SIT In order to allow simulating segment fragmentation in large section scenario, this patch reduces the candidate range: * if curseg is the last segment in the section, return curseg->segno to make get_new_segment() itself find the next free segment. * if curseg is in the middle of the secion, select candicate randomly in the range of [curseg + 1, last_seg_in_the_same_section] to keep type consistent. Signed-off-by: Sheng Yong <[email protected]>
Reviewed-by: Chao Yu <[email protected]> Thanks, _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
