Orchid XP v8 wrote:
> You're telling me an I/O-bound process is slowed down by the mere act of 
> changing CPU mode? I thought that stuff was more or less instant!

No. When you add up all the cache misses, the TLB flushing, the 
privilege mode changes, the checking of addresses, and all that, it 
comes out to about 30% of the CPU compute-power being spent on that, 
compared to running on bare metal with all that turned off. And you're 
still talking O(N^2) instead of O(N) behavior.

> Well, true, but a directory entry is about 12 bytes,

It wasn't even 12 bytes back in unix v7 of CP/M. :-) With more modern 
file systems, the files are hashed or sorted into the directories.

 > so you'd need to be
> deleting several *thousand million* files, not just 3,000.

Uh huh.  Takes about 2 hours on the machine I have at work to delete two 
months of audio chopped into 20-second chunks. :-)

-- 
Darren New / San Diego, CA, USA (PST)

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