chatty "switching to keychain-db" console messages in Sierra
I wouldn't worry about chatty messages in general as the logging subsystem is now database driven and can handle thousands of messages a minute with little or no load on the system.

You can get a nice overview of your log statistics and see if this is truly one of the larger users of logging. This command does take a while to chew throat the 30 million events I have on my MacBook (3 to 5 minutes) - but even that is a trivial load on my system in practice given how optimized and power efficient Apple macOS logging is now.

log stats --overview
== archive =============================================================
size:               571,895,056 bytes
                    2,118,164,524 bytes (uncompressed)
start:              Tue Aug  1 06:33:03 2017
end:                Wed Sep 20 04:54:41 2017
statedump:          7,343

events:             [       total        log      trace   signpost ]
                    [  30,724,811 27,173,212        996    409,431 ]

activity:           [      create transition     action ]
                    [   3,132,338          0        201 ]

log messages:       [     default       info      debug      error      fault ]
                    [  26,698,888    667,559     38,352    143,035     35,805 ]

ttl:                [        1day      3days      7days     14days     30days ]
                    [     409,447 26,551,227    259,646    204,137    166,525 ]

processes:          
          [        events (%total),  decomp. bytes (%total),                           image UUID, image ]
          [    14,796,212 ( 48.2%),    983,897,959 ( 46.5%), EA3CE30B-81E9-3DEA-95F3-CDACA642C5BD, kernel ]
          [       396,296 (  1.3%),    133,190,047 (  6.3%), 5AA6AB96-6A89-3E62-9BB4-6CA2913647C9, secd ]
          [       664,086 (  2.2%),     75,896,057 (  3.6%), 99B2EC04-B281-3EBF-8541-6F6FC3273D9C, identityservicesd ]
          [       299,166 (  1.0%),     60,314,374 (  2.8%), 83FF3BD0-0A23-3232-A28A-C1A5297DA516, dasd ]
          [       727,099 (  2.4%),     53,298,516 (  2.5%), 15049F04-4C48-3D01-ABC2-8DC751F0B9E3, cloudd ]

senders:            
          [        events (%total),  decomp. bytes (%total),                           image UUID, image ]
          [    13,883,766 ( 45.2%),    943,025,476 ( 44.5%), 0086A982-E384-3ABF-AD20-BF1300E02E42, Sandbox ]
          [       394,150 (  1.3%),    133,130,846 (  6.3%), 5AA6AB96-6A89-3E62-9BB4-6CA2913647C9, secd ]
          [     1,653,215 (  5.4%),     67,618,576 (  3.2%), D7DDB735-A244-3A06-A432-135E9E368B51, CFNetwork ]
          [       294,803 (  1.0%),     60,187,838 (  2.8%), 7DC1094C-EF1A-3621-9A6B-DEDF467D64DF, DuetActivitySchedulerDaemon ]
          [       393,191 (  1.3%),     58,538,606 (  2.8%), 99B2EC04-B281-3EBF-8541-6F6FC3273D9C, identityservicesd ]


For context - this machine runs beta software often - gets beat up in all manner of ways, Xcode, buggy apps, beta versions of Microsoft Office, beta OS with enhanced logging profiles.