From: John Carter <john.carter@...>
Date: 2007-07-18T10:32:10+09:00
Subject: Re: Spin buffers

On Wed, 18 Jul 2007, MenTaLguY wrote:

And yes... I did, as always, measure before I optimized and my Queue
of Array trick did speed things measurably.

> Depends on the version of Ruby.  It certainly is if you're using
> fastthread.  If he's not using fastthread, I'd recommend giving it a
> try.

I'm not using fastthread since it caused code that had been working
fine for several years to curl up and die. So I disabled it.

I'll admit I never got to the bottom of why it did.... (and no, it
wasn't the code that used my queue of arrays trick)

>>> This "Spin Buffer" trick looks Good...
>>>   http://www.ddj.com/dept/architect/199902669?pgno=2
>>>
>>> Anyone have a ruby Spin Buffer implementation lying around?

> "Spin Buffers" are _snake oil_; they get their "speed" at the expense of
> correctness -- the implementation given in the DDJ article is not
> threadsafe.

Well that was a bit of a problem with the article... it didn't
actually include the code so I can't say one way or the other on
that. Any pointers as to what the incorrect bit is?



John Carter                             Phone : (64)(3) 358 6639
Tait Electronics                        Fax   : (64)(3) 359 4632
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