[NTLUG:Discuss] ext3 waste disk spaces then Windows ME?

[Stuart Johnston]

Terry wrote:
> On 4/25/06, Pat Regan <thehead at patshead.com> wrote:
>> m m wrote:
>>> All:
>>>
>>> I just found this:
>>>
>>> " ... Ext3 has the worst inital capacity (92.77%), while others FS preserve
>>> almost full partition capacity (ReiserFS = 99.83%, JFS = 99.82%, XFS =
>>> 99.95%). Interestingly, the residual capacity of Ext3 and ReiserFS was
>>> identical to the initial, while JFS and XFS lost about 0.02% of their
>>> partition capacity, suggesting that these FS can dynamically grow but do not
>>> completely return to their inital state (and size) after file removal."
>>>
>>> from
>>>
>>> http://www.tuxmachines.org/node/6396
>>>
>>> According to the article abovem it seems that the XFS is "better" than ext3.
>>> ext3 must be good at some points, otherwise why the most distro use it?
>>> Anyone have the idea?
>>>
>> Somebody needs to tell the author of that article about the fact that
>> mke2fs reserves 5% of the filesystem for root by default.  That would
>> bring your number for ext2 up to almost 98%.
> 
> What do you mean "mke2fs reserves 5% of the filesystem for root"
> (The "for root"  part is what I don't understand.)
> The only two concepts of root  I know of are the root file system and
> the root directory ( / & /root ), but I know you aren't talking about
> either of those, right?

In this case it is the root user ("root" can be kinda confusing in Unix 
terminology).  The idea is that when a file system starts to run out of 
disk space, the space reserved for root will keep the system functioning 
enough that you can login and clean-up.  Coincidentally, I learn that 
fact on this very mailing list about a year ago!  :-)

-Stuart