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Date: Fri, 28 Jul 2006 08:01:06 +0200
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To: Ilia Alshanetsky <ilia@prohost.org>
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Subject: Re: [PHP-DEV] memory_get_usage with new Memory Manager
From: bertrand@toggg.com (bertrand Gugger)

Ilia Alshanetsky wrote:
> 
> On 27-Jul-06, at 9:03 AM, bertrand Gugger wrote:
> 
>>
>> That may hear off topic , but how you enable something else than 8M  
>> *without* getting this counting overhead ?
> 
> 
> Eh? When you set a limit what are you trying to do? From my  experience 
> most of the time this setting is used by hosting providers  to restrict 
> memory utilization of various PHP scripts to avoid out-of- memory 
> situations and system abuse.
The most cases I saw were providers or production site wanting to grant 
*more* than 8M (typically 16M) to their customers / users.
I dont call that a "restriction".
You should know this 8M limit is reached very easily.
e.g. lot of popular CMS wont work below this limit as soon as they have 
a litle contents.
> As such you'd want as accurate  measurement 
> as possible including any overhead and what not, since it  is possible 
> to use the overhead to exceed or in some cases even to  bypass the 
> memory limit entirely.
You miss the point , they don't care about accuracy,
they just don't want the default 8M but more.
> 
>> It looks to me that --enable-memory-limit mixes 2 independant roles :
>> - setting the amount of available memory, and enabling eventually  
>> local setting,
>> - enabling the evaluation of the process consumption.
> 
> 
> That is correct. Memory limit by its nature requires PHP to count the  
> amount of memory consumed, since such tracking is performed it  enabled 
> PHP to report internally via functions (or via Apache log)  about its 
> memory utilization.
I have no idea how it works internally ...
Are you meaning the default "hard-coded" 8M limit is magic and will not 
need to count the amount of memory consumed but any custom setting will ?
-- 
toggg