AH00051: дочерний pid XXXXX отказов Сегментации сигнала выхода (11), возможный coredump в/etc/apache2

Я обновил до mysql 5.7 с помощью этого Обновления MySQL 5.5 MySQL 5.7

С тех пор мы получали 500 на всех размещенных веб-сайтах, и apache2 журнал ошибок содержит

[Thu Jul 07 03:52:24.807409 2016] [core:notice] [pid 1624] AH00051: child     pid 11486 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:32.819761 2016] [core:notice] [pid 1624] AH00051: child pid 11482 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:32.819853 2016] [core:notice] [pid 1624] AH00051: child pid 11489 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:35.824422 2016] [core:notice] [pid 1624] AH00051: child pid 11490 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:42.833487 2016] [core:notice] [pid 1624] AH00051: child pid 11493 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:46.839680 2016] [core:notice] [pid 1624] AH00051: child pid 11494 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:52.847820 2016] [core:notice] [pid 1624] AH00051: child pid 11495 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:52:56.852889 2016] [core:notice] [pid 1624] AH00051: child pid 11498 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:53:06.864664 2016] [core:notice] [pid 1624] AH00051: child pid 11500 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:53:07.867806 2016] [core:notice] [pid 1624] AH00051: child pid 11504 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:53:35.899735 2016] [core:notice] [pid 1624] AH00051: child pid 11506 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Jul 07 03:53:39.906559 2016] [core:notice] [pid 1624] AH00051: child pid 11509 exit signal Segmentation fault (11), possible coredump in /etc/apache2

Конфигурация сервера: Ubuntu 14.04, Mysql:5.7, PHP 5.5.9, Apache 2.4.7