Segmentstion faults was the reason v2.2.7 was downloaded from git rather than using v2.2.5 deb package.
With PHP 5.x you must be using 2.2.7 or 2.2.8 or 3.1.3>. PHP 7 must be 3.0.0 >.there has been alot of change this year so i would recommrnd staying up to date using PECL currently 3.1.4 for both PHP versions.
https://pecl.php.net/package/redis
See Php-Redis 3.1.1?