T4 chip is a major departure from previous designs. The T4 offers a maximum of eight cores per physical chip and keeps the T3's eight-threads-per-core limitation. The T4 compensates for its lower maximum theoretical throughput in several ways. First, the T4 is an out-of-order processor with an enhanced branch predictor. Its maximum speed is said to be at least 3GHz, nearly double that of the 1.67GHz T3. Oracle claims the chip's single-threaded performance has been significantly boosted, and expects T4 to deliver a 2x-7x speed increase in single-threaded workloads compared to T3."
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