Does anyone have any idea what this means?

I just found this in my system log:

Nov 17 13:00:46 kernel: nvram: consolidating space!

I have never seen that before. Since when does this router perform such an action? Does anyone have any information?

Thanks.

Edit: Here it is again in my RT-AC87R system log:

Nov 17 17:56:22 kernel: nvram: consolidating space!

Is there anyone who knows what this means, exactly? Anyone? I do not remember seeing this entry before today.