Well, whatever it's doing it needs (tried to allocate 20480 bytes) 20,480 bytes more of memory!!! (or so it says)
Is this an all in one server where apache and mysqld live on same machine? How are you running Apache?
What's the 'top' of the 'top' command show? (memory)
So, wonder if you need some tweaks for MySQL. Install MySQLTuner ... a perl script that looks at stats for DB server and config ... gives recommendations for tweaking.
In the 'show debugging' info shared ... total-vm:10675180kB ... does that mean that's the total memory of server? 10.6 Meg?