Re: [VOTE] 64 bit platform improvements for string length and integer

From: Date: Fri, 31 Jan 2014 16:29:20 +0000
Subject: Re: [VOTE] 64 bit platform improvements for string length and integer
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On 1/31/14 4:10 AM, Jakub Zelenka wrote:

On Fri, Jan 31, 2014 at 11:57 AM, Pierre Joye <[email protected] <mailto:[email protected]>> wrote:



    On Jan 31, 2014 12:54 PM, "Jakub Zelenka" <[email protected] <mailto:[email protected]>> wrote:



- before the patch: 8B (ptr) + 4B (int) + 4B (alignment) = 16B
- after the patch: 8B (ptr) + 8B (size_t) = 16B

That seems like no increase to me. Is there anything else that I missed?


    size_t will be 8 bytes on most architecture. That's 4 bytes more than what we have now for buffer length (using int).


Yeah but the final size of zval is the same. With int the memory is aligned and the extra 4 bytes are not used. It means that the size for
zvalue_value was 16B on 64bit anyway (see above). On 32bit the size of size_t and int is 4 bytes so there is no difference - 8 bytes for zvalue_value.

Regards

Jakub


A Linux benchmark to verify the impact would have been useful.

Chris

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