Mod: add comment and modify log level

[fangyincheng]

No description provided.

[codecov-io]

Codecov Report

Merging #492 into develop will increase coverage by 0.24%.
The diff coverage is 60.00%.

@@             Coverage Diff             @@
##           develop     #492      +/-   ##
===========================================
+ Coverage    66.44%   66.69%   +0.24%     
===========================================
  Files          184      184              
  Lines         9700     9700              
===========================================
+ Hits          6445     6469      +24     
+ Misses        2620     2595      -25     
- Partials       635      636       +1     

Impacted Files	Coverage Δ
common/proxy/proxy.go	93.06% <ø> (ø)
common/rpc_service.go	86.25% <ø> (ø)
common/url.go	67.68% <ø> (ø)
...lter/filter_impl/tps/tps_limiter_method_service.go	80.00% <ø> (ø)
protocol/dubbo/client.go	67.87% <ø> (ø)
protocol/dubbo/codec.go	77.50% <ø> (+5.00%)	⬆️
protocol/dubbo/config.go	13.15% <ø> (ø)
protocol/dubbo/dubbo_exporter.go	100.00% <ø> (ø)
protocol/dubbo/dubbo_invoker.go	82.25% <ø> (ø)
protocol/dubbo/dubbo_protocol.go	91.83% <ø> (ø)
... and 12 more

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[zouyx]

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