I've ran out of ideas

Arne Wörner arne_woerner at yahoo.com
Thu Nov 18 19:21:36 PST 2004

--- Luke <lukem at cse.unsw.EDU.AU> wrote:
> On Thu, 18 Nov 2004, Arne Wörner wrote:
> > Hmm... Since /dev/zero delivers on my box about 100-300MByte/sec 
> > (100Mbyte/sec for 512byte block size), it looks like your network driver 
> > hinders the throughputting proceedings (I assume, that your other 
> > network devices can handle 90Mbit/sec; no ethernet collisions, no 
> > concurrency, ...). Are you sure, that Linux performs better in the same 
> > setting?
> I think you must mean Mbps, not MBps. If it were bytes, you would be 
> saturating 2.5 gigabit links with a single connection. Not to mention 
> most PCI busses.
neo# dd if=/dev/zero of=/dev/null bs=512k count=1000
1000+0 records in
1000+0 records out
524288000 bytes transferred in 1.475860 secs (355242396 bytes/sec)

I meant /dev/zero, which does not use PCI or so (it just produces zeros; that's
why it is so fast). Just the bus between processor and main memory, I think...
With my 133MHz FSB(?) my DDRAM can do 8Gbit/sec??? I am not so good in such
things... Looks like each byte gets copied three times before it reaches
/dev/null... Does somebody agree?

Maybe my contributions are too weird and misleading, but I do not see, that
they are technically wrong.


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