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Date: Wed, 13 Jan 2010 13:40:32 +0100
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To: Sebastian Bergmann <sb@sebastian-bergmann.de>
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Subject: Re: [PHP-DEV] About optimization
From: mathieu.suen@easyflirt.com ("mathieu.suen")

Sebastian Bergmann wrote:
> Am 13.01.2010 12:18, schrieb mathieu.suen:
>   
>> I would like to know why the opcode is not optimized.
>>     
>
>  Because any optimization, even very simple ones, impose a performance
>  penalty in the default execution model of PHP which does not use a
>   
>  bytecode cache.
>   

For simple optimization I don't think so. Take the simple example:


function foo()
{
    $a = 45;
    return $a;
}

Here if you don't optimize you are creating a variable. So you put 
pressure on the gc and the memory.
Best would be some benchmark.
By the way why there is no native bytecode cache ?


>  Only when the bytecode is not regenerated for each execution does it
>  make sense to invest for time for the then one-time compilation.
>
>   

Sorry I don't understand what do you mean?

-- Mathieu Suen