APPLIED column of gv$archived_log not updated on primary

Oracle RDBMS 11.1.0.7 using Data Guard (not active) on RAC 11.1.0.7

We implement Data Guard to a standby site about 40 miles away.  The morning of Aug-05 we had an expected network outage.  To prepare for this I turned DG off until the next morning.   That morning, we turned DG back on, switch some logs, and at the standby site logs started applying and we were happy.  We look at this using gv$archived_log on the standby, but don't always look at gv$archived_log on the primary.

Today when looking at gv$archived_log on the primary, I see that starting on Aug-05 the column APPLIED is not always updated with the information that the apply happened on the standby.  We've had this before and discovered the fal  process wasn't keeping up, and did the fix of find the fal arc process and doing a kill-9 on it.  That worked a few times in the past, soon thereafter the applied column was keeping up.  Today, though, it's not.  While the standby shows logs are applied, the primary doesn't know about it, but intermittenly.