Darren New wrote:
> Orchid XP v8 wrote:
>> Well, you say all that, but if I do the same operation using the CLI 
>> instead, it's instantaneous.
> 
> I don't know about NT-era OSes, but I remember that for a long time, the 
> CLI used the DOS 1.0 interface for deleting files, because it let you 
> specify wildcards. Hence, you had one kernel call that would delete all 
> the files.
> 
> If you use a UNIX-like interface, you have to do "find file, delete 
> file, find file, delete file, find file, delete file, ...." So on a 
> directory with a half-million files, you scan the thing a quarter 
> million times on average (on ext3, at least) or you at least wind up 
> doing a whole bunch of kernel calls if you have a file system that's a 
> little better organized about the file layout.

Seems like it's the same amount of work to me, whether the kernel does 
it or the application does it.

> To be fair, NTFS and 
> other tree-based directory systems have to rework the tree when you 
> delete the files, so this too will be disk I/O overhead.

Um... you don't cache directory blocks, no? (Especially given that 
they're usually non-contiguous and so take a lot of thrashing to access, 
and there often heavily accessed.)

>> Dude... where do you even buy that much disk space??
> 
> Fry's. Best Buy. Circuit City. Any place that sells hard drives. Go down 
> to the store, shell out $500, and pick up a couple terabytes.

$500 seems like a hell of a lot of money to me...

But then, 1 TB seems like a hell of a lot of space too. I have 0.3 TB 
that I've never come close to filling yet.

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