Casper.Dik at Sun.COM wrote:
> 
> >Test case:  watch "iostat -xnzc 5" while reading from an
> >optical media, using different block sizes:
> >
> >dd if=/dev/rdsk/c2t1d0p0 of=/dev/null bs=2k
> >dd if=/dev/rdsk/c2t1d0p0 of=/dev/null bs=32k
> >
> >This SONY DVD RW AW-G170A (and a DVD-RW media)
> >is reading ~3 MB/sec using 2k read requests, and ~8 MB/sec
> >when using 32k reads.
> 
> While this matters some, the current install process is so inefficient
> that even though installing from DVD is slower than the network, a network
> tends to be idle most of the time during the install.
> 
> (Which isn't surprising as getting 4GB over local net should not take more
> than between 40 (Gbps) and 400s (100Mbps) but installs take generally a lot
> longer than 7 minutes; bunzip2 is also so slow that it cannot stream data
> from any media faster than papertape.

"bunzip" could be made a bit faster with some simple tricks (like using
higher optimizer options for the compiler, use largepages for the
buffers etc.) ... but it would need a sponsor for such a patch
(<rant>which is unlikely to happen since I am already sitting on at
least half a dozend bugs/RFEs awaiting sponsorship and noone cares...
;-( </rant>) ...

----

Bye,
Roland

-- 
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 (o.\ \/ /.o) roland.mainz at nrubsig.org
  \__\/\/__/  MPEG specialist, C&&JAVA&&Sun&&Unix programmer
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 (;O/ \/ \O;)

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