• Yokemate of Keyboards
    Yokemate of Keyboards
    Posts: 12113 from 2003/5/22
    From: Germany
    > an ARM11 700MHz based device would be faster than an e300/400MHZ.

    When takemehomegrandma claimed two weeks ago in this very thread that an 800 MHz ARM11 core outperforms a 400 MHz e300c4 core I called him out on that. Needless to say that he has failed to provide evidence.

    > From raw computing power I think it should be more than two times
    > as fast as the e300/400 (about 1800 MIPS vs. 800 MIPS AFAIK).

    With "MIPS" you mean "DMIPS", right? DMIPS performance of MPC5200B's e300c0 is only 4% less than that of e300c4, so they're about on par. 1800 DMIPS for 700 MHz would mean about 2.6 DMIPS per MHz for ARM11. That would be more than Cortex-A9 (2.5 DMIPS per MHz), so very unlikely. Where do you have that figure from? According to ARM Ltd. the ARM11 core delivers about half that performance, namely between 1.18 and 1.54 DMIPS per MHz (depending on the specific type of ARM11 core) and thus between 826 and 1078 DMIPS at 700 MHz. Add to this that the Dhrystone benchmark is probably not suited to benefit from a processor's out-of-order execution capability which the e300 provides but the ARM11 does not.

    DMIPS per MHz figures for different ARM11 types:
    1.18: http://www.arm.com/products/processors/classic/arm11/arm1136.php?tab=Performance
    1.25: http://www.arm.com/products/processors/classic/arm11/arm1136.php?tab=Specifications
    1.25: http://www.arm.com/products/processors/classic/arm11/arm1176.php?tab=Specifications
    1.41: http://www.arm.com/products/processors/classic/arm11/arm1156.php?tab=Performance
    1.54: http://www.arm.com/products/processors/classic/arm11/arm1156.php?tab=Specifications

    I don't know which one of these cores the BCM2763 incorporates though.
  • »26.05.11 - 11:56