st_blksize This field gives the "preferred" block size for efficient filesystem I/O. stx_blksize The "preferred" block size for efficient filesystem I/O. (Writâ?? ing to a file in smaller chunks may cause an inefficient read- modify-rewrite.) File offsets aren't explicitly mentioned, but I think it's implied they should be a multiple of st[x]_blksize, just like the I/O size. Otherwise, the I/O would obviously require reading/writing partial blocks. So, the proposed stx_offset_align_optimal field sounds like the same thing to me. Is there anything I'm misunderstanding? Putting stx_offset_align_optimal behind the STATX_DIRECTIO flag would also be confusing if it would apply to both direct and buffered I/O. - Eric
