Weird errors

[avansant]

While my site isn't down, I'm seeing a lot of error files in the cache all of a sudden, that say:

a:1:{i:0;a:2:{s:4:"c_id";s:3:"771";s:9:"master_id";s:3:"213";}}

I'm also getting "Excessive Resource Usage" notices from my server:

Time: Tue Jul 8 08:05:43 2014 -0400
Account: doodle
Resource: Virtual Memory Size
Exceeded: 303 > 300 (MB)
Executable: /usr/bin/php
Command Line: /usr/bin/php /home/doodle/public_html/index.php
PID: 21918 (Parent PID:20817)
Killed: No

What are these strings trying to tell me?

[mc12345678]

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ZC version?
Plugins installed?
Etc...