Changes between Version 6 and Version 7 of Machines


Ignore:
Timestamp:
04/18/08 18:46:19 (15 years ago)
Author:
norris
Comment:

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Legend:

Unmodified
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  • Machines

    v6 v7  
    77  * true 64-bit counters in BG/P and all counters for PAPI always starting from a true zero (no write allowed) 
    88  * 455 total native counters, max multiplexing: 256 
     9  * Implementation details: The BG/P hardware performance counters are the values of special CPU registers. Each 64-bit counter is split into a 12-bit low-order portion and a 52-bit high-order portion. Implemented as SRAM array, the high-order logic sequentially polls the low-order counters and increments an SRAM word if the overflow bit of the corresponding low-order counter is set. Each counter can be configured to generate an interrupt if a specified threshold value is reached.  
    910 * PAPI counter tests: 
    1011  * available [wiki:bgppapi PAPI counters] (not including native)