For shared hosting, big /tmp partition is recommended. If /tmp is too small then you may face /tmp full issue.
How to increase /tmp partition in cpanel
First stop cpanel, apache, mysql services.
Now unmount /tmp and /var/tmp
umount -l /tmp
umount -l /var/tmp
Move /usr/tmpDSK file to another location (just in case you’ll need to mount it somewhere else to preserve data):
mv /usr/tmpDSK /usr/tmpDSK_back
Now run following command.
sed -i -e ‘s/512000/2048000/g’ /scripts/securetmp
ln -s /var/lib/mysql/mysql.sock
Once completed, restart all the service.