# Memory alignment **URL:** \ **Category:** Ruby\ **Created:** [April 22, 2007, 3:09pm UTC](https://www.ruby-forum.com/t/memory-alignment/92649 "2007-04-22T15:09:00Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Detlef\_R](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Post date:** [April 22, 2007, 3:09pm UTC](https://www.ruby-forum.com/t/memory-alignment/92649/1 "2007-04-22T15:09:00Z")
Hi, in an C extension i need to generate ruby strings, where str-\>ptr is aligned to a 16 byte boundary. This is necessary so that the data can be used with simd engines (AltiVec, SSE, …). Is there a way to do this? Cheers detlef ---
**Author:** ![Detlef\_R](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Post date:** [April 22, 2007, 3:51pm UTC](https://www.ruby-forum.com/t/memory-alignment/92649/2 "2007-04-22T15:51:05Z")
Detlef R. wrote: > There’s no way to tell Ruby to align its strings this way. Your only option is to make a copy aligned to your needs. ---
**Author:** ![Detlef\_R](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Post date:** [April 24, 2007, 2:42am UTC](https://www.ruby-forum.com/t/memory-alignment/92649/3 "2007-04-24T02:42:15Z")
On 4/22/07, Timothy H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > detlef > > There’s no way to tell Ruby to align its strings this way. Your only option is to make a copy aligned to your needs. Without looking at the ruby source code to see if there is a hack for alignment, one thought that occurs is to create your string 16 bytes larger than required – find the correct offset that is aligned, do the work and then adjust the string as necessary to the correct start. pth