Is Codeigniter 3 php 7 ready?

> But shouldn't PHP7 be up to twice as fast as PHP 5.6. ?

Year, php7 is overall twice faster than php 5.6.

But the benchmarks everybody says are about Linux, not Windows.
I'm not sure Windows php7 is as fast as Linux.

And php7 does not guarantee your app would be twice faster, because apps have many bottle necks.

You can see benchmarks of many apps by Rasmus (about one month ago):
http://talks.php.net/tokyo15#/drupalbench

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