RBR Channel waits

BANNER                                                                              CON_ID

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Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production              0

PL/SQL Release 12.2.0.1.0 - Production                                                    0

CORE    12.2.0.1.0      Production                                                                0

TNS for Linux: Version 12.2.0.1.0 - Production                                            0

NLSRTL Version 12.2.0.1.0 - Production                                                    0

3-node RAC cluster

Patch level:

Patch  26710464     : applied on Sun Nov 12 01:04:08 CST 2017

Unique Patch ID:  21632407

Patch description:  "Database Release Update : 12.2.0.1.171017 (26710464)

We are seeing sporadic spikes in 'log file sync' waits, that I have been investigating.  I have been working through Doc ID 1376916.1 to determine if these waits can be explained by application activity, or if there is something more nefarious going on.  There are no obvious signs of errors or delays in the lgwr trace files, so I'm combing through the AWR reports.