In the last episode (May 09), Amandeep said:
> Amandeep wrote:
> >>>>>>The transfer rate is about 15MB/s
> >>>>>>
> >>>>>>when I run
> >>>>>>#dd if=/dev/zero of=/usr/junk bs=8192
> >
> >OK with the above dd
> >
> >dd if=/dev/ad0 of=/dev/null bs=64k
> >
> >it gives me 56MB/s. from the start.
>
> So how does the block size makes the difference?? What is the true
> transfer rate.?
At the moment, 56MB/sec :)
Those two speeds aren't directly comparable, since your first was
testing writes through the filesystem with a small blocksize, and the
second was testing reads to the raw device with a large blocksize.
Usually reading, using raw devices, and using large blocksizes are
faster then writing, using a filesystem, and using small blocksizes, so
all three changes probably contributed a little to the speed
difference.
--
Dan Nelson
[EMAIL PROTECTED]
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