Re: Performance of access type : a tiny mistake in the WikiBook ?

["(see below)" <yaldnif.w@blueyonder.co.uk>]

On 08/10/2009 00:30, in article
31da5154-9739-4ead-8437-aaa5d70dc7e8@h30g2000vbr.googlegroups.com, "Yannick
Duch�ne Hibou57" <yannick_duchene@yahoo.fr> wrote:

> Hi Bill, and thanks for your reply
> 
> On 8 oct, 00:38, "(see below)" <yaldni...@blueyonder.co.uk> wrote:
>> surely it should indicate the likely effect of the "not null"
>> and "access constant" options as well.
> That's a relevant comment indeed
> You're right with that point
> 
> I came into it because I'm seeking about common performance
> considerations. So I've found this article on WikiPedia.
> 
> I'm also seeking about informations on the average impact of inlined
> in generics. The same WikiBook states it has bad impact on
> performance, in the way it prevents the compiler from using code
> sharing. But I wonder if it applies only to the actually inlined
> methods or to the whole package.
> 
...

Do you have any solid reason to believe that such micromanagement has a
significant effect on your program's performance? If it has, it might well
be contrary to such generalized rules of thumb as the Wikibook propounds.

I have a 14KSLOC program that runs three times as fast when I inline the
appropriate (small, but heavily-used) subprograms.

It runs *half* as fast if I replace the 3-statement body of one of these
subprograms by 2 statements that seem "obviously" more efficient.

The only way to answer such questions is to experiment with the
alternatives, after you've done the really difficult stuff (i.e., getting it
right, for now and for the foreseeable future), and then have a demonstrated
need for better performance.

-- 
Bill Findlay
<surname><forename> chez blueyonder.co.uk