:throughput.  For example, on the PIII-850 (116MHz FSB and SDRAM, its
:overclocked) here on my desk with 256KB L2 cache:
:
:dd if=/dev/zero of=/dev/null bs=512k count=4000
:4000+0 records in
:4000+0 records out
:2097152000 bytes transferred in 8.229456 secs (254834825 bytes/sec)
:
:dd if=/dev/zero of=/dev/null bs=128k count=16000
:16000+0 records in
:16000+0 records out
:2097152000 bytes transferred in 1.204001 secs (1741819224 bytes/sec)
:
:Now THAT is a significant difference.  :-)

    Interesting.  I get very different results with the 1.3 GHz P4.  The
    best I seem to get is 1.4 GBytes/sec.  I'm not sure what the L2 cache
    is on the box, but it's definitely a consumer model.

    dd if=/dev/zero of=/dev/null bs=512k count=4000
    2097152000 bytes transferred in 2.363903 secs (887156520 bytes/sec)

    dd if=/dev/zero of=/dev/null bs=128k count=16000
    2097152000 bytes transferred in 1.471046 secs (1425619621 bytes/sec)

    If I use lower block sizes the syscall overhead blows up the 
    performance (it gets lower rather then higher).  So I figure I don't
    have as much L2 as on your system.

                                                -Matt

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