https://bugs.kde.org/show_bug.cgi?id=462033
--- Comment #12 from Andrius Štikonas <andr...@stikonas.eu> --- (In reply to Teddy from comment #11) > This is Theodore's comment: > > That's working as intended. Dumpe2fs is reading from the superblock > on disk, and the Linux kernel is quite deliberately not updating most > fields in the superblock until the file system is unmounted. > > There are a couple of reasons for this. The first is that frequent > updates of the superblock is costly in terms of wasted I/O; it > requires taking a random seek to update the superblock on disk, and > that I/O operation and throughput is better used for real work. > > The second is that updating some of the fields is simply costly. It > would require taking a global lock to update the fields, which reduces > the file system's scalability across a large number of CPU cores. The > ext2 and ext3 file system (before it was removed from the kernel; the > ext4 kernel code now provides ext3 support) used to update the total > free blocks and free inodes, and this turned out to be a major > Scalability bottleneck. This is why we don't do it any more. :-) > > Yes, it means that a system administrator which tries to monitor free > blocks usage using dumpe2fs won't be able to do it any more. But the > proper, and more portable way of getting that information was to use > the df command. Thanks, so it might make sense to switch to df... -- You are receiving this mail because: You are watching all bug changes.
