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• Google protobuf generated messages are not zero garbage, and the serialized Protobuf messages are technically reusable so for very low latency applications that aren't using the Platform's zing distribution, this can result in garbage related pauses. 

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Xbuf

Xbuf generated objects, are backed by the X Platform's high performance implementation of Google protobufs which supports zero garbage operation and cut-through serialization (the ability to read/write fields directly to from a backing buffer). It should be used for applications with the most stringent performance requirements. 

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• Accessors for String and Uuid arrays fields in Xbuf are not currently zero garbage. Consequently, Xbuf may be more expensive than Protobuf for types that use array fields. 

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Xbuf2

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