RE: Performance

[Chris.Kaiser@...]

That's along the lines of what I'm thinking..

Pull the business rules from a database when they change, 
plug em' into a C++ template, compile, link, and then refresh 
the network's copy. The clients would reload the dlls on a cycle. 

Although, I also need to be able to generate new logic. But simple
logic. Walk a tree of rules based decisions and generate the resulting
C++ while satisfying a generic interface that the clients can depend
on. Probably using the same templates. 

This is all still in the R&D phase, ...ideas are welcome :) 

Chris

> -----Original Message-----
> From: David Jeske [mailto:jeske@chat.net]
> Sent: Tuesday, November 06, 2001 10:57 AM
> To: Multiple recipients of list
> Subject: Re: Performance
> 
> 
> On Tue, Nov 06, 2001 at 10:47:08AM -0800, 
> Chris.Kaiser@peoplefirst.com wrote:
> > One good reason why, and one that I need, is to convince management
> > that its a worthy solution to some dynamic code generation problems.
> > 
> > My boss wants me to generate compiled C++ on the fly based on the
> > user communities mods. 
> 
> Okay. I presume this is for performance reasons?
> 
> > We're to build a series of tools to enable the user community to
> > change the business rules on the fly. I'd like for these rules to be
> > generated in lua and parsed from our C++ engine.  But I need to
> > convince him that it will be fast enough.
> 
> If this is for performance reasons, then I doubt a lua dynamic
> compiler will be fast enough. The "cost" of executing lua is as much
> in the design of the language as a weak-typed hashtable based
> scripting language as it is because it's an interpreted VM. Dynamic
> compilation can get complicated and only takes care of half the
> problem.
> 
> Remember the famous quote:
> 
>   Premature optimization is the root of all evil in programming. 
> 
>                ---C.A.R. Hoare
>                      (often misattributed to D. E. Knuth,
>                       who was himself quoting Hoare) 
> 
> If you think Lua will be fast enough, use it. However, if Lua needs a
> dynamic compilation engine to be fast enough, then just render C code
> during configuration, compile, link, and go.
> 
> -- 
> David Jeske (N9LCA) + http://www.chat.net/~jeske/ + jeske@chat.net
>