PowerBook G4 1GHz STREAM

From: Choon Peng Chng (choonpeng@mac.com)
Date: Sat Jan 18 2003 - 02:09:07 CST

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    Hi,

       I've compiled STREAM from source:
    gcc stream_d.c second_wall.c -o stream_d_wall -lm -O3 -mcpu=7450
    -funroll-all-loops
    where gcc is Apple's GCC based on version 3.1.

    Machine specs:
    Apple Titanium PowerBook G4
    PowerPC G4 7450 @ 1GHz
    256KB L2 cache
    1MB L3 cache
    133MHz system bus
    512MB SDRAM
    Mac OS X 10.2.3
    Darwin kernel version 6.3

    Results:
    -------------------------------------------------------------
    This system uses 8 bytes per DOUBLE PRECISION word.
    -------------------------------------------------------------
    Array size = 400000, Offset = 0
    Total memory required = 9.2 MB.
    Each test is run 10 times, but only
    the *best* time for each is used.
    -------------------------------------------------------------
    Your clock granularity/precision appears to be 3 microseconds.
    Each test below will take on the order of 133294 microseconds.
        (= 44431 clock ticks)
    Increase the size of the arrays if this shows that
    you are not getting at least 20 clock ticks per test.
    -------------------------------------------------------------
    WARNING -- The above is only a rough guideline.
    For best results, please be sure you know the
    precision of your system timer.
    -------------------------------------------------------------
    Function Rate (MB/s) RMS time Min time Max time
    Copy: 460.6278 0.0147 0.0139 0.0202
    Scale: 463.5671 0.0141 0.0138 0.0155
    Add: 465.4089 0.0266 0.0206 0.0565
    Triad: 471.4218 0.0205 0.0204 0.0206

    Strangely, this is lower than the submitted results for the PowerMac
    867MHz?
    Also, if I compile with second_cpu.c instead, I got better results but
    with:
    Your clock granularity/precision appears to be 9999 microseconds.
    Each test below will take on the order of 10000 microseconds.
        (= 1 clock ticks)

    I notice some submitted results reports this. Isn't this wrong?

    regards,
    choon-peng



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