Table 1. Comparison of Alpha 21164 and 21264 Processors
21164 (ev5,ev56) 21264 (ev6, ev67)
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Dual issue Quad issue
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Simple branch predictor Tournament branch predictor
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Direct mapped, write-through cache Two-way set associative cache
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Simple instruction scheduling rules Complex instruction scheduling rules
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Roughly twice the bandwidth of the 21164
New instructions: WH64, CTLZ, CTTZ
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