Large SQL File

Hello, I have around 10 WordPress sites. I was in my server last night and noticed one of the SQL DB files was huge compared to others, it is over 6GB where as most of my SQL files are 10-100mb. Granted, the site relative to the 6GB SQL file is my biggest site, but 6GB?

So, I did some investigation and spoke with my server company who are always very helpful. He tells me that most of the space in the file is taken up by wp_mbp_ping_optimizer

What is this? Can the SQL file be cleaned of this data? Should I be worried?

Thanks, in advance.