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It does not have any impact on SDK. SDK still works with this log. You might want to change log level for io.netty package to INFO.

Are native epoll bindings required?

Before first call to a remote API you can get the following exception, logged on DEBUG level:

9:27:09.888 [main] DEBUG io.netty.util.internal.NativeLibraryLoader - netty_transport_native_epoll_x86_64 cannot be loaded from java.libary.path,
       now trying export to -Dio.netty.native.workdir: /tmpjava.lang.UnsatisfiedLinkError: 
       no netty_transport_native_epoll_x86_64 in java.library.path: [/usr/java/packages/lib, /usr/lib64, /lib64, /lib, /usr/lib]
    at java.base/java.lang.ClassLoader.loadLibrary(ClassLoader.java:2660)
    at java.base/java.lang.Runtime.loadLibrary0(Runtime.java:829)
    at java.base/java.lang.System.loadLibrary(System.java:1867)
    at io.netty.util.internal.NativeLibraryUtil.loadLibrary(NativeLibraryUtil.java:38)
    at io.netty.util.internal.NativeLibraryLoader.loadLibrary(NativeLibraryLoader.java:349)
    at io.netty.util.internal.NativeLibraryLoader.load(NativeLibraryLoader.java:136)

As in the latter case this is only a DEBUG log. The library will fall back to Java NIO. In order to get rid of this log you may either change log level or add dependency on native transports.

CBS Client

When cbsClient.updates() will yield an event?

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