This read-create value reports the total time, in 10-millisecond units, that this LSP's primary path specifically has been operational, as opposed to any standby or secondary paths that may have carried traffic during primary-path outages. Dividing csMplsLspPrimaryTimeUp by csMplsLspTimeUp and multiplying by 100 gives the percentage of the tunnel's total up time that was actually spent on its preferred primary path, as the description itself notes. An administrator seeing this ratio drop significantly would recognize the tunnel has been relying on a backup path far more than expected, warranting investigation of the primary path's stability.