Re: defragmentation of boot related files

[Andreas Dilger <adilger@dilger.ca>]

On 2010-08-26, at 14:16, andreas@rid-net.de wrote:
>>> Usage: e4defrag -r directory...| device...
>>>       e4defrag -r base_file move_file...<--- new
>>> 
> 
> The new interface looks nice. As I see it's easy to implement cause only the main-function must be modified. If you have no objections, I will do it myself and send you the patch to review it.
> 
>> I suspect the original idea would work better because it is more
>> likely to pack the libs / files into perfectly contiguous block
>> ranges.
> 
> I don't know if it makes a difference for the block allocator. Even though you know the size of all files to be moved.
> 
> For a better result, may it be possible to create a base_file whose inode is part of an empty block group?

There is a /proc/fs/ext4/*/inode_goal that will cause new inodes allocated in the filesystem to be after the specified goal inode.

I suppose it would also be possible to have e4defrag simply take an inode number in the form "<inode_number>" in place of "base_file", as debugfs does.

Cheers, Andreas