[LU-6824] improve error messages for dir htree limit

Related — Thu, 18 Oct 2018 22:46:02 +0000

Currently without large dir feature, ldiskfs directory hash tree will be limited 2 height, this means directory size is limited about 1GB, and in fact users are likely to hit ENOSPC when reaching half of limit because of bad hash.

    
LDISKFS-fs warning (device dm-4): ldiskfs_dx_add_entry: Directory (ino: 614516572) index full, reach max htree level :2
LDISKFS-fs warning (device dm-4): ldiskfs_dx_add_entry: Large directory feature is not enabled on this filesystem

Testing by following scripts:

    
    i=0
    filename="aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaabbbbbbbbbbbbbbbbbbbbbbbb"
    while [ 1 ]
    do
            touch $filename"$i"
            if [ $? -ne 0 ];then
                    break
            fi
            ((i++))
    done

When directory size grow about 590M, we hit ENOSPC. this patch try to improve error messages to warn users when it is easier to hit ENOSPC (50% of limit).

Whamcloud Community JIRA

[LU-6824] improve error messages for dir htree limit