> -----Original Message-----
> From: Marcus Boerger [mailto:[EMAIL PROTECTED] 
> Sent: Friday, March 14, 2008 8:24 PM
> To: Stas Malyshev
> Cc: Dmitry Stogov; Andi Gutmans; phpxcache; internals@lists.php.net
> Subject: Re: [PHP-DEV] Patch for opcode caches
> 
> 
> Hello Stanislav,
> 
> Friday, March 14, 2008, 5:51:49 PM, you wrote:
> 
> >> But that means we are compiling inheritance when a file is loaded 
> >> form the cache. The goal should be to compiling inheritance when 
> >> writing to the opcode cache file. All we achieve here is a 
> slow down. 
> >> If there is
> 
> > You can not do that. You do not know that until runtime.
> 
> >> something that makes this required than at least we need 
> to warn the 
> >> user about the slow code. I Think what we need to do is 
> deprecating 
> >> class and
> 
> > It won't be slow. It would be much faster (in some cases 
> 10x faster).
> > This specific assembly of instructions might be slower in 
> some cases, 
> > but the code altogether will be faster. That's the idea of 
> the opcode 
> > caches.
> 
> >> namespace use in non main blocks as well as include and require in 
> >> non main blocks. And if there is no such case than 
> everything can be 
> >> bound early which is the fast state we should aim for.
> 
> Lemme just think, doing inheritance at compile time before we 
> send the stuff to an opcode cache can be slower then?

It's always faster, but with opcode caches we cannot always do it in
compile-time, because the parent (in another file) might be changed on
next load of children class.

> How is 
> that possible? After all late binding means we do it at run 
> time. And no matter how much faster we can do it. It will 
> always be slower than doing the same thing only once.
> 
> > We do not need to deprecate anything, and inheritance can 
> not be bound
> > before parent class is known, which in the case of bytecode 
> cache means 
> > - not before the file is loaded from the cache. That's 
> exactly what this 
> > patch enables. It does not change performance 
> characteristics of neither 
> > cached not non-cached code, it just makes it much simpler 
> and working in 
> > all cases.
> 
> Inheritance cannot be done before the parent class is known. 
> We still need to do the prototype checks even if we assume 
> the class is there and insert a virtual class as parent somehow.

Right. This is the reason why we need to delay early binding. But we
don't like to delay it to run-time, because it will breake the class
creaton order and as result may breake some scripts.

Thanks. Dmitry.

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