On Sun, 11 May 2008, Eric Sosman wrote:
> Lew wrote:
>> Eric Sosman wrote:
>>> No. "Suggestive," perhaps, or even "cautionary." But for
>>> my own part I wouldn't confer "very indicative" on a lab result
>>> that cannot be reproduced by an independent experimenter. A
>>> citation of a full re****t or published paper or something of that
>>> nature might change my mind, but at the moment ... no.
>>
>> OK, that's fine. It was something that convinced me that it worked in
that
>> case because I could interact with people who conducted the test. You
>> choose to reject the anecdote because I have no credibility with you.
>
> No, no, no, Lew: Your credibility is just fine (or my credulity; take
> it either way). All I'm saying is that the information you've presented
> is insufficient to sup****t the inference Tom Anderson drew from it
> ("kind of damning for filesystems"), and that he should consider being a
> little less hasty in drawing sweeping conclusions from sketchy and
> incomplete re****ts.
I'm not saying filesystems are worthless. Just that when it comes to
shunting data on and off a disk, the fact that a different method can work
five times faster than a filesystem means that if you're in the business
of shunting data on and off a disk as fast as possible, a filesystem is
probably not a great idea.
Of course, if there was some particular reason why there was such a big
difference in this case that doesn't apply in all or most cases, then fair
enough, i'm over-generalising. I can't think of what that might be,
though.
> If someone told you there was a "five-to-one difference" between
> ArrayList and plain array, would you conclude that this was "kind of
> damning" for Collections? Of course not. I'm urging Tom not to make
> the analogous error.
If someone (credible) told me that there was a five-to-one difference in
times for an ArrayList.get and an array[], then, if we were in a context
where performance was im****tant, i certainly would take that as kind of
damning for collections. I think that's perfectly reasonable.
tom
--
It's almost over now.
|
