I ran into an issue where a user was spamming and queue up thousands of email in our cPanel server. To clear it out, I did this:

/etc/init.d/exim stop

/etc/init.d/exim start

I had about 120k emails in queue and it took about 20 seconds to remove them all. If you want to fine tune it, you can have exim delete only specific emails in queue:

grep -lr 'a certain string' /var/spool/exim/input/ | \sed -e 's/^.*\/\([a-zA-Z0-9-]*\)-[DH]$/\1/g' | xargs exim -Mrm

Credit to: http://bradthemad.org/tech/notes/exim_cheatsheet.php
 

To delete frozen emails from a specific email address:

exiqgrep -i -f luser@example.tld | xargs exim -Mrm

If you just want to delete mail queue directories, sometimes faster delete:

/var/spool/exim/input and the /var/spool/exim/msglog directories

I had a client trying to import a 200M zip file to phpmyadmin to import into his MySQL database, he kept receiving this error:

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 201380904 bytes) in /usr/local/cpanel/base/3rdparty/phpMyAdmin/libraries/zip_extension.lib.php on line 65

It ends up that phpmyadmin is using its own php.ini config, and defaults the memory size to 128M.

Edit the file : /usr/local/cpanel/3rdparty/etc/php.ini.dist

there is a line that says memory_limit, change that to what you’d like. I changed mine to 264M.

You will want to restart cPanel as well:

/etc/init.d/cpanel restart

You will lose this setting upon reboot, so if you want to keep it, you will want to run this:

echo "/usr/local/cpanel/3rdparty/etc/php.ini.dist" >> /etc/cpanelsync.exclude

This will exclude the file when it goes to sync/update with cPanel.