gaps in hobbit graphs

Hi All,

Any idea what would / could cause gaps in graphing like in the attached picture?
It happens periodically on various systems, but only on a few particular graphs (like CPU utilization).

Thanks for looking!

Mike Wood
UNIX System Administrator
Kinetic Concepts Inc.
XXXX NW Parkway
San Antonio, TX, 78249

E-mail:  user-ca9fdeef37c9@xymon.invalid
Office:  (XXX) XXX-XXXX
Mobile:  (XXX) XXX-XXXX


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